CAD Standards & Procedures Manual

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CAD Standards

&

Procedures Manual

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CAD Standards and Procedures Manual

Overview

This manual describes the conventions, procedures and suggested working practices to be used for the preparation of CAD drawings within the NG Bailey Organisation. It is intended to aid CAD users to produce uniform drawings with greater efficiency and present a recognisable image of NGB, associated with clear, accurate presentation.

This uniform approach to drawing production will allow more flexibility for sharing work and movement of staff between jobs, departments and offices.

The manual is written solely for AutoCAD 2014 and specifically ‘Autodesk AutoCAD Architecture 2014’ with the inclusion of the BailCAD suite of tools.

Standardisation plays an important role in the exchange of information. It helps keep consistency both in house and with other design team members. It should be remembered at all times that drawings are regularly passed on to other team members in digital format.

Changes to current office standards should apply to new projects only, and is at the discretion of that office’s CAD manager.

Where project specific CAD procedures are required then they should be read in conjunction with this manual but project specific standards should always take precedence over this manual.

The project number 12345 used throughout this manual is indicative only.

Feedback

All content within this CAD Manual has been written with the input and agreement of all the branches of NG Bailey Ltd. however it is not ‘set in stone’ and may be subject to change using the correct procedure. It is unacceptable for any branch to adopt new ways of working without consulting the CAD Systems Management (CSM) Team, the reasons for this are as follows:

 It may be a better way of working and therefore all the branches should utilise it.

 There may be a better solution.

 Other branches may need to be asked for their opinion.

The procedure for changes is to see your branch representative who will refer it back to the CSM Team, who in turn will correspond with all branches to seek the best solution. The new procedure will then be implemented to all the branches ensuring all staff benefit.

The CAD Standards Management (CSM) Team welcomes feedback from users to enable us to create a user-friendly system. If you have any ideas for further customisation, additional layers, suggestions, or just need some advice, please e-mail your comments to:

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Directory Structure

The directory structure indicated here should be adopted and strictly adhered to for all projects. A description of the usage of each directory/folder is detailed below.

1-Registers

This directory is used to store all drawing issue sheets and drawing document transmittal slips. The documents may be in electronic format (excel or word files) or may be scanned images of hand written documents. Scanned images are to be saved in PDF format. It may be acceptable on projects where online portals are in use to rely on the electronic drawing logs automatically created by the portal when drawings are issued (e.g.: 4projects, Build-Online, Buzzsaw etc.) Please seek confirmation from project management as to the particular project requirement.

2-NGB_Drawings

This directory is used to store all electronic drawing files that have been created and/or amended by NG Bailey. This directory contains many sub-directories the purpose of which is detailed below:

archive: Archive directories are to be accessible to all members of the project team.

../archive/old_x-refs: When xrefs are updated, the superseded xref files are to be suffixed with the current date in the format ‘_YYYY-MM-DD’ and moved from the xref directory to this archive directory.

../archive/record: On completion of project record drawings, a bound copy of the .dwg file is copied to this directory.

issued: As a minimum, .DWF files are to be created for all issued drawings on each project. Individual DWF files are to be created for each drawing. Drawing filenames are to be structured as company standard (see page 7) and suffixed

with _rev-X (where X denotes drawing revision). The IssuePLOT utility (part of the BailCAD suite of tools) automatically creates, names, binds xrefs and copies to the correct directory in all the electronic drawing formats listed below. IssuePLOT can be configured to produce whichever formats are required. The Issued sub-directories are to be accessible by all members of the project team.

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../issued/navis: This directory contains copies of any Navisworks models that have been produced and issued. These files are never created by IssuePLOT and will always need to be placed here manually.

../issued/pdf: This directory contains copies of every issued drawing in .pdf format.

Not shown in the above image (for reasons of clarity) are instances of ‘superseded’ folders inside each of the issued folders. These folders are generated automatically by IssuePLOT and any previous issues of drawings are moved into here automatically when a new issue is done, thus meaning that inside each of the top level issued directories you will only see the latest issued revisions of drawings. If users are not using the BailCAD IssuePLOT facility then this process will need to be carried out manually.

working: this directory contains the live copies of .dwg files that are continually developed and updated throughout the project. Access to these folders should be restricted to Design and CAD personnel only. All files within these directories are to be structured and named in line with company standard (see page 7). It is company standard, where possible, to create individual .dwg files for each drawing service/level. Only where services are required to be coordinated together should information be combined within the same drawing file. Where services are coordinated together on a single model the filename will be a meaningful description prefixed with md_ (md being shorthand for model).

../working/bwk: This directory contains the working .dwg builderswork files.

../working/coord: This directory contains the working .dwg coordinated services drawings. Where coordinated service drawings indicate individual services (i.e. ductwork, pipework, electrical containment etc.), these are differentiated from design drawings by field 2 of the drawing number e.g. an uncoordinated ductwork design drawing would be numbered 12345- M57-0101. Following detailed coordination, the drawing may be issued with the number 12345-C57-0101.

../working/details: This directory contains working .dwg details & section drawings.

../working/elec: This directory contains working .dwg electrical services drawings. (Where services are subject to coordination e.g. electrical containment, this folder would contain uncoordinated design layouts)

../working/mech: This directory contains working .dwg mechanical services drawings. (Where services are subject to coordination e.g. ductwork/pipework, this folder would contain uncoordinated design layouts)

../working/models: This directory contains working .dwg coordinated service models. Drawing filenames will all be prefixed with md_ to denote that multiple drawings are created from each model. Typical filenames would be md_first.dwg, md_second.dwg for coordinated first and second floor services. Model files do not contain drawing sheets. The model is x- referenced into a separate file containing the drawing sheet. This file resides in the relevant working directory.

../working/schematics: This directory contains working .dwg schematics

../working/misc: This folder contains temporary CAD files specific to the project (snippets of drawings or wblocks that are exchanged between CAD/Design team members).

../xrefs: this directory contains all the latest architectural and structural information in .dwg format that is currently in use on the project. All files are to be optimised (cleaned up) and formatted to NG Bailey standards (see page 13) and renamed with an x_ prefix. Any xref files that are revised shall have the date suffixed to the old copy, which shall then be moved to the archive/old_xrefs folder.

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Field 1 (YYYY-MM-DD): this field is a record of the date the drawings were received. This date is to be written in the format indicated in order to arrange folders in date order when viewed in Windows Explorer.

Field 2 (media): denotes the media source of the data and will be either: email, ftp, web, cd, dvd, fd. Where a large quantity of drawings is received on CD or DVD it can be wasteful to copy all files to the server. In this instance a folder should be created containing a readme.txt file. This file should indicate where the CD is stored and its contents.

Field 3 (received-from): this field records who the information was received from. Words are to be separated by hyphens.

There are certain instances where it may be advantageous to create sub-folders within the K3 folder for the individual 3rd parties. If it is deemed suitable that a project works in this way then the folder structure should be clear and concise i.e. Architect, Structure etc with no ambiguous descriptions used. Within these folders you should still maintain the folder structure detailed above with the exception of removing the third field as this is obviously not required.

Project Directory Creation

Project directory creation is usually under the control of a limited number of personnel within each branch. When a new project directory is created it should contain the entire K folder structure as depicted on page 4 rather than limited sections with spurious naming. If this system is not adhered to then many of the automated systems within BailCAD will fail to operate and QA procedure will not be followed.

Should you require a copy of the blank folder structure to place into a new project, a complete structure can be found at R:\cad\AutoCAD\-= New K Folder =-

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File Naming

Single Tab Drawings

At the simplest level, where a drawing file contains only one drawing, the filename should be the same as the drawing number (see page 9). This file is saved to the appropriate working directory. The first character of the second field of the drawing number denotes the correct folder (e.g. M, E, C, B, S or D would be mech, elec, coord, bwk, schematics or details respectively).

Where .dwg files are more complex and contain more than one drawing there are a number of ways in which these can be named and referenced on disk.

Multi Tab Drawings

When a dwg file contains a number of related single service drawings, using a separate paper space tab for each drawing sheet is the most suitable method.

The drawing file in this instance would be named to indicate which drawings are to be found within the file e.g. 12345-E66-0001-0003.dwg would indicate the following drawings are contained within the file:

 12345-E66-0001.dwg

 12345-E66-0002.dwg

 12345-E66-0003.dwg

When tabs are used they should be renamed as the individual drawing numbers above to indicate which drawing sheet is on which tab.

Note: If BailCAD IssuePLOT is used to issue any of the tabs in a multi-tab drawing, an individual file is created, named and placed within the correct issue directory. The filename is created from the drawing number on the drawing sheet, not the file or tab name. IssuePLOT automatically converts forward and backward slashes to hyphens.

Coordinated Model Files

When coordinated models are produced the files are to be suitably named and prefixed with the characters ‘md_’ examples include:

 md_first.dwg first floor coordinated services

 md_second.dwg second floor coordinated services

 md_third.dwg third floor coordinated services

When a coordinated model is produced the drawing file should not contain any drawing sheets. Individual files should be created for each drawing. These files include the drawing sheet, specific notes and the model file x-referenced in. The individual files are to be saved in the appropriate service folder in the working directory. The model file should reside in the working/models directory.

Issued Drawings

Each time a drawing is issued an electronic copy is either manually or automatically (automatic if IssuePLOT is used) created and stored in the relevant issued directory. To differentiate between revisions a suffix in the format _rev-n should be appended where n denotes the revision to the

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Xrefs

Where architectural and structural layouts are used within NG Bailey service drawings they shall be x-referenced into the drawing. All x-refs shall be optimised and formatted prior to use (see page 13). All current x-refs shall reside in the xref directory and the filename shall be prefixed with x_. All xrefs (prefixed x_) and model files (prefixed md_) are to be inserted into drawings at 0,0,0 and onto a layer named the same as the filename. When xrefs are revised, the old xref should be suffixed with the date in the format _YYYY-MM-DD (e.g. a file named x_ground.dwg becomes x_ground_2012-07-16.dwg). This file is then moved to the ..archive/old_xrefs folder. The new xref is then named as the original and resides in the xref folder.

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Drawing Numbering

All NG Bailey drawings are to be numbered in accordance with the following rules unless specified otherwise by the client or main contractor. The numbering system below is also included on an A4 quick guide sheet at the end of this document.

The standard drawing number is made up of three separate fields separated by hyphens ‘-’: No other form of separator should be used and no superfluous spaces should be added e.g.

12345-M57-0101

The drawing numbering system has been designed so that it can be used at a simplistic level for projects with very few drawings, or at a more complex level where additional information can be coded into each field for larger projects. Irrespective of how the numbering system is used, the drawing number will always consist of three fields of fixed length. The numbering system has also been designed so that drawings can be filed/viewed alphabetically.

Field 1 is the unique project number. This is usually a five digit number but may be longer and contain characters for tender projects. There is no need to add a project team number to this field as each team has its own unique prefix forming part of the contract number.

Field 2 is three characters in length. The first character denotes the drawing type/discipline and will always be one of the following:

Field 2 Discipline Codes

S Schematics C Co-ordinated Services Drawings

E Electrical Services Drawings B Builderswork Drawings M Mechanical Services Drawings D Details, Sections or Sketches

The second and third characters of field 2 denote the service and will be selected from the tables below. The first character determines what combinations are valid. These codes are based on those used for layering as defined in BS 1192 (AUG Layer naming conventions). If there is a service not documented here which you need to use (e.g. Controls) then you should utilise one of these ‘spare’ categories for this and document it in your project documentation. At the time of writing, BS1192 is being updated and as such there may be additional codes added in the near future which take up some of the current ‘spare’ options but until such time as this happens, please continue in the manner described above.

Mechanical Services Drawings (first digit M, S or C)

50 General (or mixed) mechanical services 55 Chilled Water/Refrigeration 51 Spare (used for project specific purposes) 56 Heating (Mechanical Pipework)

52 Drainage 57 Ventilation (Ductwork)

53 Domestic Services 58 Public Health

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Co-ordination Drawings (first digit C)

S0 Mechanical & Electrical Services 50 Mechanical Services 60 Electrical Services

Builderswork Drawings (first digit B)

Details & Sketches (first digit D)

Where codes C, B or D are used, the following characters can be used optionally in place of the third digit.

P Plantrooms L Low Level Services (floor level / floor void)

V Services above ceiling void H High Level Services C Services at ceiling level

Field 3 is four characters in length and, as standard, denotes floor level and sequence number. This field can be tailored to suit any drawing description. Examples of use are provided towards the end of this section. For projects with very few drawings field 3 can be 0001, 0002, 0003 etc. etc. This contains no level information yet still gives a compliant drawing number when used with field 2 (e.g. M50 or E60 is sufficient for projects with very few drawings)

The first pair of characters of this field is used to denote the floor level examples include: B2 - Basement Level two floors below ground

B1 - Basement Level one floor below ground 00 - Ground Floor

01 - First Floor

02 - Second Floor etc. etc.

E0 - External at Ground Floor level

E1 - External at first Floor Level etc. etc. (e.g. open roof levels or wall mounted lighting) M0 - Ground Floor Mezzanine Level

M1 - First Floor Mezzanine Level etc. etc.

For drawings indicating services which are not confined to a particular level the following codes can be used:

AA - Drawings relevant to All Areas

RA - RA riser A, RB riser B or R1 R2 etc. etc. (or more suitably R001, R002 etc.) Z1 - Zone 1, Zone 2 etc. etc.

The second pair of characters is a sequential number beginning at 01 to 99. This allows up to 99 drawings of the same service per level.

A simple single side A4 prompt sheet is included at the end of this manual as a reference for drawing numbering and naming.

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Drawing Set-Up

Drawings should always be created using the standard Bailey template files. These templates are set to load automatically when launching AutoCAD and also when using the QNEW option. They can be found in C:\BailCAD\support should you need to locate them manually. These templates contain basic text styles and define the layering standard as BS1192 AUG Version 2. Drawings are set with metric units and to use CTB files.

The following table details where objects should be placed within an AutoCAD drawing.

Modelspace Paperspace

General drafting geometry Drawing Border

External references SHE Box

Services Revision Clouds

Text (Excluding 3D Coordinated models) Text (3D Coordinated models only) Dimensions (Excluding 3D Coordinated models) Dimensions (3D Coordinated models only)

Legend (Optional) Legend (Optional)

Notes (Optional) Notes (Optional)

Where details are required on a drawing at various scales it must not be achieved by drawing to scale. The drawing in model space should always be created full size (1:1 scale) in millimetres. All scaling should be achieved using the AutoCAD zoom XP utility through paper space.

To avoid problems with overlaying information the drawing rotation must never be altered; do not move, re-scale or rotate drawings. The orientation should only be altered by changing the UCS or by using the Dview twist command - both of these methods have their own advantages and achieve the same result.

When exiting a drawing, ensure that all required layers are turned on and ready for plotting with the full view displayed on the screen. This not only enables the viewer to see the drawing on the preview but also assists with batch plotting.

Drawings should be purged and audited regularly. Only objects that are not being used on the drawing will be removed.

On the BailCAD ‘Drawing Sheet Tools’ ribbon panel you will see the ‘Insert Sheet’ routine for inserting NG Bailey title blocks in paperspace at 1:1. Only one sheet should be inserted onto any paperspace tab. The insertion routine will not allow more than one sheet to be inserted and copying, pasting and moving of inserted sheets should be avoided.

Standard borders are provided in A0, A1, A2, A3 and A4 sizes. All sheets are in landscape orientation. Sheets should not be modified in any way without prior consent of the CSM Team and NGB Marketing.

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There are a number of system variables which are pre-set within files created by BailCAD in order to provide a degree of uniformity in drawings.

Variable Value Effect

ucsicon 1 UCS icon is turned ON

xloadctl 2 Turns Xref demand loading ON

indexctl 3 Layer and spatial indexes are created and stored in the drawing

sdi 0 Enables ‘Multiple Document Environment’

isavepercent 0 Ensures saves are carried out in entirety. tempoverrides 0 Turns Temporary Override keys off xreftype 1 Sets Xref insert type to overlay by default

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Xrefs and Models

Where Architectural, Structural or Co-ordinated model layouts are used within NG Bailey service drawings they shall be inserted as external references. All x-refs shall be optimised and formatted prior to use. All current x-refs shall reside in the xref directory and the filename shall be prefixed with x_

Use of x-refs

Xrefs are to be positioned at 0,0,0 (unless project requirements dictate otherwise) and inserted on a layer with the same name as the x-ref file name. The xref 'type' should be set to 'Overlay' and the xref 'path type' should be set to 'relative path'.

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This block does not need to be positioned so as to be visible when plotting the drawing – after all, there is some data there which does not need to be referenced by anybody outside the CAD department.

If you want to show details of attached references in your drawing you should then use the BailCAD Xref Info Block (PS) tool. This utility will look at each attached xref and read the data within the info block. It then creates an additional paperspace block on the drawing sheet detailing which files are attached. When using IssuePLOT, this block is automatically inserted and updated each time an issue is carried out. Its insert point is automatic but if it interferes with a drawing layout it can be relocated to a more desirable location. Once the block has been moved in this manner, its position will be retained whenever it is updated either manually or automatically when using IssuePLOT.

If for any reason the xref needs be rotated/moved, this is to be done once it has been attached to a drawing. Do not rotate the original architectural file. The suggested standard would be to make the intersection of the two lowest numbered gridlines line up with 0,0,0. (One of these grids should then be aligned to the horizontal). Service Model drawings attached as xrefs should follow the same

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located when drawing files are transferred electronically (e.g. if the complete K folder was written to CD or DVD then relative paths will ensure drawings view correctly)

Optimising x-refs

Most of the service layouts that NG Bailey produces will incorporate Architectural and/or Structural drawings produced by others. These electronic drawing files are produced to many different standards and often contain many elements that are not required to be part of our service drawings (e.g. contour lines, mapping references, furniture, finishing details etc.) In order to make our drawing process as efficient as possible the xref files should be optimised and cleaned up prior to use. Optimising xrefs can be as simple as deleting elements we will never require, but for poorly produced drawings it can be a lengthy process. The local CAD manager should determine whether the benefits gained from spending time optimising xrefs outweigh the inefficiency associated with using drawings that contain large amounts of non-required data. There are a number of steps that can be taken to optimise xrefs which include, but are not limited to:

Deleting content that is not required: In a well-structured drawing, content that is not required can be simply turned off or frozen by layer. Frozen layers do not get read into memory and therefore regeneration times are kept to a minimum (although archive drawings that have x-references bound will include them which increases file size). Switching layers off merely hides entities from view and does not provide any performance gains. For complex drawings, the xref can be split into a number of smaller files that can be loaded as required, e.g. furniture, ceiling grids, floor grids etc. can be separated out (wblocked) and x-referenced into the drawings that require them.

Deleting all paperspace content: Architectural drawings often contain numerous paperspace drawing sheets and views. These will not be required by NG Bailey.

Setting all entities to colour by layer and setting xref layers to colours 250-253 – 250-253:

These shades of grey have been adopted by the majority of the building services industry as the preferred colour for architectural xrefs. Using a light shade of grey for building outlines enhances the services elements and makes the drawing a lot easier to work with. The darker the shade the thinner the pen i.e.: 250 finest lineweight, 253 boldest lineweight.

Convert all text to an efficient clear font face: Rendered and True Type fonts require a lot of additional processing. Also plot files that contain TTF's are substantially increased in size adding unnecessarily to network traffic and printer workload. Where possible, Romans font face should be used.

Use Standard Linetypes and ensure global and entity scales are set correctly: Linetypes viewed at incorrect scales drastically reduces viewing and plotting performance, and increases plot file size. There is little difference between many of the predefined linetypes. Users should try and limit linetype styles to Center, Dashed, Hidden and Phantom as these can be easily differentiated on screen and on paper.

Purge all non-referenced content from drawings: If a drawing contains block references, linetype styles, text styles, layer names etc. that are not actually used or have been deleted from the drawing, they still exist as part of the drawing database and can lower performance and increase file size. Purging the drawing removes all such references and cleans out any non-referenced items. It is advisable to run purge a number of times to ensure all unnon-referenced blocks

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which can be run by typing ‘kill' at the command prompt. Kill deletes all Null text strings. Starting with the release of AutoCAD 2010, there is now the option to remove null text strings using the purge command.

Truncating Layer Names, Block Names, Text, Styles, Dim Styles & Linetype styles: When an xref is bound to a drawing, the above names have the drawing name prefixed to them using $0$ as the delimiter. Running the BailCAD truncate function (Utilities>Clean-Up Tools>Truncate) removes the prefix.

Removing 3D content that is not required: If an xref contains lines with thickness, speed is reduced.

Deleting duplicate entities: Overkill is an Express Tools function that deletes any duplicated entities from a drawing. It is not uncommon for architectural drawings to have several copies of all CAD data contained within the drawing. Running overkill can significantly increase drawing efficiency.

Include xref file name & revision: When an xref is included as part of an NG Bailey drawing, it is good practise to indicate the drawing number and revision from which it was created. An attributed ‘Xref Info’ block is located on the BailCAD ‘Utilities’ menu and should be inserted into each drawing and filled in. When the drawing is part of the background for a Bailey drawing the block should then be viewed in the notes column of the Bailey plotted drawing by means of an mview.

Data should not be relocated away from the original survey grid, as sometimes it is a requirement that all drawing/model files are to be positioned in the correct location over the OS Map. The setting out position should remain constant throughout the project.

In order to try and introduce a common approach to the way reference files are cleaned and optimised, we have now compiled a tool which does all of the above listed jobs and a lot more. By using such a tool, it aids you in getting rid of some of the more complicated errors that are often found in incoming drawings and means that you don’t miss or forget any aspects of the task. This tool is fully detailed in the BailCAD Utilities Panel section (see page 52).

Caution should be used in the modification of Xrefs as a change made by one person will affect all drawings using that file. Write access to Xref directories could be restricted to experienced CAD staff only if required. Read access will always be available.

Colours and Line Weights

There are four colour tables provided within BailCAD. These should provide ample flexibility when producing drawings and should be adhered to wherever possible as this will help to produce consistent plotted output between users and locations.

The plot styles have been created to compliment the use of CADmep+ and BailCAD ‘straight from the box’, therefore customisation of these systems is not advised.

STB files are not provided as they are not catered for when using CADmep+. Standard NGB Colour Tables

_NGB Standard.ctb For general black and white prints.

_NGB Colour.ctb For colour prints with text (yellow) set to plot in black _NGB Generic.ctb Used for incoming drawings with no CTB provided. _NGB A3 Reduced.ctb Used to provide reduced lineweights on scaled plots.

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Layering

Unless otherwise instructed by a client/main contractor, all drawings produced by NG Bailey shall be layered in line with the convention detailed below which is based on BS1192 Part 5.

The layer is broken into 4 fields – Discipline, Category, Descriptor and Element.

Only the first two fields are required to comply with the BS1192 layering standard but NG Bailey drawings will use all four with the exception of drawing sheet layers and block insertion layers which have no sub-elements.

Field 1 denotes the Author/Discipline and within NG Bailey will be either:

M - Mechanical Engineers.

E - Electrical Engineers.

Note: Other fields exist within the code to cover disciplines such as Heating & Ventilation engineers, Public Health engineers and Voice & Data engineers. For our purposes we will use only the M or E designation.

Field 2 denotes the service category. The Bailey standard uses just the main service category numbering as detailed in BS1192 Part 5.

Field 3 is a text descriptor used to detail the sub-category of a service

Field 4 denotes the type of graphical entity. This field is not required for compliance with BS1192 but is always used within the BailCAD layering system.

Field 4 will be one of the following four character codes:

GRA 2D Graphics

ATT Attributes

TXT Text

DIM Dimensions

It should be noted that the fourth field is to be kept at three characters in order to avoid confusion with layers created by CADmep+ which uses the same layering convention but field 4 is just 2 characters.

Examples:

E620_SML_PWR_GRA Electrical, Small Power, 2D Graphic E670_FA_SOUND_ATT Electrical, Fire Alarms, Attribute

M560_MTHW_DIM Mechanical, Medium Temp Hot Water, Dimension

BailCAD includes tools to automatically create compliant layering and includes all those detailed below. Fuller details can be found in the BailCAD Electrical and Mechanical sections (pages 35 and

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Note that the *** is shown here for reference only and depicts the three character variants of field 4.

Mechanical Layers

500 – GENERAL MECHANICAL SERVICES

Controls & Wiring - LV M500_CONTROLS_LV_***

Controls & Wiring - ELV M500_CONTROLS_ELV_***

Mechanical Block Insertion M500_BLK_INS_G (Final character can change _{depending on insert ‘level’ – G = General)}

520 - WASTE DISPOSAL, DRAINAGE

Below Ground Drainage M520_BLW_GRD_***

Condensate Drainage M520_COND_DRN_***

Rain Water Pipe M520_RWP_***

Soil & Waste Drainage M520_SOIL_WST_***

Vent Pipe M520_VENT_***

530 - WATER AND LIQUID SUPPLY

Boosted Cold Water System M530_BCWS_***

Mains Cold Water M530_MCWS_***

Domestic Hot Water M530_DHWS_***

Domestic Cold Water M530_DCWS_***

Dry Riser M530_DRY_RISE_***

Fuel & Oil Supplies M530_FUEL_OIL_***

Ground Source Water M530_GRND_SRC_***

Laboratory Cold Water M530_LCWS_***

Sprinklers M530_SPRINKLERS_***

Tank Cold Water M530_TCWS_***

540 - GAS SUPPLY

Compressed Air M540_COMP_AIR_***

Natural Gas M540_NAT_GAS_***

Medical Gas M540_MED_GAS_***

550 - SPACE COOLING, REFRIGERATION

Chilled Water M550_CHW_***

Condensor Water M550_COND_***

DX Tray M550_DX_TRAY_***

Refrigeration DX M550_DX_***

560 - SPACE HEATING

Condensate M560_COND_***

Heat Recovery M560_HEAT_REC_***

LTHW-CT M560_LTHW-CT_***

LTHW-VT M560_LTHW-VT_***

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570 - VENTILATION

Boiler Flue Dilution M570_FLU_DIL_***

Exhaust M570_EXHAUST_***

Fresh-Air Makeup M570_FAMU_***

Fume Extract M570_FUME_EX_***

Fume Hood Extract M570_FUME_HD_***

General Extract M570_GEN_EXT_***

General Supply M570_GEN_SUP_***

Kitchen Extract M570_KIT_EXT_***

Nitrogen Extract M570_N20_EXT_***

Recirculation M570_RECIRC_***

Smoke Extract M570_SMK_EXT_***

Toilet Extract M570_WC_EXT_***

580 - PUBLIC HEALTH AND RAW WATER

590 - PARTS, ACCESSORIES TO MECH SERVICES - FLUES, FLUE LININGS, BOILERS

General Plant ME_590_GEN_PLNT_***

Electrical Layers

600 - GENERAL ELECTRICAL SERVICES

Electronic E600_ELECTRONIC_***

HV & LV Switchgear E600_HV-LV_SWITCH_***

Schematic E600_SCHEMATIC_***

Metering E600_METERING_***

Electrical Block Insertion E600_BLK_INS_G (Final character can change _{depending on insert ‘level’ – G = General)}

610 - ELECTRICAL SUPPLY

Supply & Distribution Equipment E610_SUPP_DIST_***

HV Containment E610_HV_CONT_***

LV Containment E610_LV_CONT_***

Sub-Main Cabling E610_SUB-MAIN_CABLE_***

620 – SMALL POWER

Small Power E620_SML_PWR_***

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640 – COMMUNICATIONS

650 – TELECOMMUNICATIONS

Data & Communications E650_DATA_COMM_***

Data & Comms Containment E650_TELE_CONT_***

Data Cabling E650_DATA_CCT_***

660 – TRANSPORT

670 - FIRE SYSTEMS

Fire Alarm Detection E670_FA_DETECT_***

Fire Alarm Sounders E670_FA_SOUND_***

Fire Alarm Accessories E670_FA_GENERAL_***

Fire Alarm Containment E670_FA_CONT_***

Fire Alarm Cabling E670_FA_CCT_***

680 - SECURITY PROTECTION

Security Cameras E680_SEC_CAMERA_***

Security Sounders E680_SEC_SOUND_***

Security Detectors E680_SEC_DETECT_***

Security Accessories E680_SEC_GENERAL_***

Security Containment E680_SEC_CONT_***

Security Cabling E680_SEC_CCT_***

690 - EARTHING

Lightning Protection E690_LTNG_PROT_***

General Earthing E690_GEN_EARTH_***

NON_SERVICE CAD LAYERS

Drawing Sheet Z010_DWG_SHEET

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Linetypes and Linetype Scale

To ensure consistency between drawings, maintain presentation and keep all line types the same in all drawings, all users should keep to the line styles provided with AutoCAD.

AutoCAD provides two linetype files: acadiso.lin and acad.lin. The acadiso.lin file is brought in with the NGB_Standard.dwt file and this should be used for most lines. The acad.lin file should not be used (this is so that linetype scaling provides better control of the output file). To stop people inserting acad.lin linetypes by mistake it is an option to overwrite the acad.lin file with the acadiso.lin file so both files contain the correct linetypes.

The linetype scale command (LTS) sets the size of each line style based upon the scale it is viewed at. As a general rule, in model space the LTscale should be set to the proposed drawing scale, hence a typical 1:50 drawing should have an LTscale of 50. When there is only one viewport in a layout then the PSLTscale should always be set to 0.

A utility is provided on the BailCAD ‘Utilities’ ribbon panel to create custom annotated lines should they be required, to depict containment, pipe or duct types etc. For details, please refer to page 58.

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Text

All drawing lettering (other than the title sheet) is to be in the style NGB_STANDARD and the font ROMANS.SHX. This text style is resident in the NGB_Standard.dwt template file which opens with each new AutoCAD session.

All drawing lettering is to be drawn at the correct scale so as to be plotted out at the recommended 2.5mm height and titles at 5mm height and underlined (see table below). No text shall be in bold. All general text and dimensions plot at 2.5mm high and a width factor of 0.85

All titles and emphasized text plot at 5.0mm high and a width factor of 0.85

All text with the exception of units of measurement (e.g. mm), should be typed using Mtext in upper case and line up on the left of any notation.

All annotation should be arranged such that they are read from the bottom of the sheet, or from the right hand side.

Non-standard AutoCAD fonts and TTF fonts should be avoided as these can create speed issues and problems when distributing files to third parties.

Enumerated notes should be written using Mtext and numbered using the list tool. Letters and bullets should not be used.

Drawing Scale Model Space Text Height Paper Space Text Height

1:10 25 2.5

1:20 50 2.5

1:50 125 2.5

1:100 250 2.5

1:200 500 2.5

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Dimensions

Only those dimensions essential for an understanding of the design intent or the execution of work should be given and these should not be duplicated unnecessarily. All relevant dimensions should be shown on the drawing, thereby removing the requirement for others to determine essential dimensions by interrogating the drawing.

The automatic dimensioning facility must be used for all dimensions. Do not explode dimensions into their constituent parts. Dimensions can be annotated, but dimensions should always be to scale.

Projectors should start a short distance from the outline and should be drawn at right angles to the associated dimension line extending slightly beyond it. Intersecting projection lines and dimension lines should be avoided but if found necessary then these should cross without special treatment. Dimension lines should generally be unbroken. Any axis, reference line or drawing outline should not be used as a dimension line but may be used as a projector.

The termination of dimension lines is to be indicated with obliques while leaders shall use solid arrowheads. More than one form of termination may be used on a particular drawing when it is necessary to impart a different meaning to the dimension i.e. tolerance or datum's. In such cases an explanation of the purpose should be included in the general notes.

BailCAD includes a tool to automatically create new dimension styles which are fully compliant with NGB standards. Details can be found on page 50.

Hatching

Only Standard AutoCAD hatch patterns should be used.

Do not associate hatch patterns to entities that are part of an Xref. The hatch pattern “dots” is memory hungry and should be avoided. Do not explode hatches – especially when ‘cleaning’ xrefs.

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Symbol Libraries

Blocks are available on the BailCAD Electrical and Mechanical ribbon panels. The electrical symbols are currently used and issued by BSRIA.

The scale for each individual block insertion can be set from the slide dialog box. The insertion scale controls individual blocks and will not scale blocks globally when altered.

All symbols are inserted with an appropriate BS 1192 base layer. The insertion layer (level) is controlled from the slide dialog box and offers a further level of manipulation if required. If the layer is not present it will create the layer. The level does not set any 3D coordinates – it is merely to create a relevant insertion layer.

Hovering the mouse over a slide will display its actual block name and description.

A generic set of NHS estates symbols is included within BailCAD but these are not layered or scaled automatically and must be manipulated manually should they be used.

The text descriptions shown in the list box are the text identifiers that are used when the user either inserts a symbol key (using the ‘Add Symbol Key’ tool) or adds a block annotation (using the ‘Annotate Block’ tool).

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If a user requires new symbols to be added to the libraries, the following procedure should be followed. This will ensure non-duplication and full company approval.

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Drawing Data Exchange

Prior to the transfer of any CAD drawings to or from another company, NGB CAD staff must agree the exact method and format with the other party.

It should be clarified which versions of CAD software is being used by all parties so that arrangements can be made to have data exchanged in compatible formats – i.e. 2000, 2004, 2007, 2010 or 2013 dwg format.

The standard NGB issue sheet should be used for all outgoing information. This form should be sent along with any drawing that is issued. Any e-mail, either incoming or outgoing, that contains drawing files should be printed off and filed.

Xref files should be sent appropriately. Generally Xrefs will not be bound but included as separate files, although sometimes recipients may ask for them bound. Good communication with other team members can save both parties time. It may also be necessary to provide any information relating to relevant object enablers that may be required for a drawing to be viewed correctly. AutoCAD’s eTransmit facility should be used to create drawing packages whenever possible. The package should always be created as a zip file and not a self-extracting exe file as these are very problematic to send via email due to security implications.

Drawings being requested from others should be requested with a full size print (A3 is an alternative) of each drawing and if necessary a layer schedule. If a drawing is required to be used within AutoCAD it should be requested in the appropriate format. It is possible since the release of AutoCAD 2007 to use DWFs and more recently Adobe PDF and MicroStation DGN files as x-ref backgrounds but DWG is still the preferred format regardless.

All drawings that are being sent out of the office are to be purged of unreferenced data; this avoids confusion and reduces the drawing file size.

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Drawing Issue

Revisions

All drawings regardless of status are to be first issued at revision 0 (zero). Subsequent revisions will step sequentially from A-Z irrespective of the drawing status. Numeric revisions are not to be used. When a drawing is issued for Record Purposes it shall be denoted RD. In some cases (possibly due to a late variation or change after Record Drawings have already been issued) it is necessary to revise a Record Drawing, when this happens subsequent revisions will be numbered R1, R2… etc.

If project/contract terms dictate that a different revision system be used, the system should be fully documented and made available to all team members. Such deviations should also be reported to the CSM Team in all instances.

Note that EVERY issue of a drawing should include a revision block on the drawing sheet - this includes the initial issue at Rev 0. Without a revision block for each and every stage of the drawings life, there is no audit trail available to trace its history should it be needed.

Revisions to all drawings should be clouded and denoted with the revision reference printed inside a triangle. Revision clouds are to be drawn in paperspace.

If using the BailCAD ‘Enhanced Revision Cloud’ tool, a cloud will be created on a layer specific to that revision i.e. Rev_Cloud - Rev A. Each subsequent revision will be placed on a new layer and all previous revision layers will be frozen off but not deleted. This allows a user to refer back to particular revision works should they be required to do so. The NGB_STANDARD colour table is configured to show all elements in black with the exception of the latest revision cloud which is coloured red.

Every time a drawing is amended and issued it must be given a new revision.

Generally only one copy of any drawing should be stored in a project working directory. When a revision is made to a drawing, a copy of the file should be created in either: PDF, DWF, PLT, or DWG (all Xrefs should be bound to this file). This file should then be placed in the ‘issued’ directory

of the project. The revision letter should be appended to the end of the file name for ease of reference i.e. 12345-M57-0101_Rev-A.dwg.

The format of ‘issued’ drawings produced will be defined by the individual project requirements and this should be determined at the outset of any new project.

The use of IssuePLOT will substantially ease the archiving process as all required output formats are created, printed, named and stored in a single process

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Drawing Status

Every NG Bailey drawing that is issued will have its status denoted in the title sheet. These are the only forms of status that should be used – no deviations. The drawing status will always be one of the following:

TENDER: Used when a drawing has been produced by NG Bailey to allow others to cost our designs/schemes, or when a drawing is to be returned with our tender with the intent of clarifying our understanding of the design brief or clearly defining our intended scope of works.

FOR INFORMATION: Used when a drawing is produced or issued to provide information about some aspect of NG Bailey's works. This information will usually only be issued for guidance or to provide a third party with an overview of a proposed or intended system. Notes should be added to the drawing clearly stating that the information presented will not be 100% accurate or complete.

PRELIMINARY: Used on drawings (usually D&B projects but not always) when issuing partially complete information, or information which is issued for discussion purposes e.g. conceptual plant layout to be tabled and discussed with Architect and structural Engineer. Notes should be added to the drawing clearly stating that the information presented is for discussion or other purposes and may not be 100% accurate or complete.

FOR COMMENT: Used when first issuing drawings on projects where NG Bailey have design responsibility. The intent is to allow other members of the design team the chance to comment on our detailed design proposals and schemes.

FOR APPROVAL: Used when first issuing drawings on projects where NG Bailey do NOT have design responsibility. The intent is to gain approval of our working drawings (which may have changed a design/drawing e.g. when coordinating services) from the consultant or person with design responsibility.

30% DESIGN REVIEW: Used when first issuing drawings for review on projects where NG Bailey has design responsibility. The intent is to allow other members of the Design team the chance to comment on our 30% design proposals and schemes.

60% DESIGN REVIEW: Used when issuing drawings for review on projects where NG Bailey has design responsibility. The intent is to allow other members of the Design team the chance to comment on our 60% design proposals and schemes.

95% DESIGN REVIEW: Used when issuing drawings for review on projects where NG Bailey has design responsibility. The intent is to allow other members of the Design team the chance to comment on our 95% design proposals and schemes.

FOR CONSTRUCTION: When all comments have been taken on board, the working drawing is issued with FOR CONSTRUCTION status. It is important to get all drawings to construction issue as soon as possible to avoid delays to the project. Nobody should install services detailed on a drawing unless it is a construction issue drawing.

RECORD DRAWING: Once all construction activities are complete the final working drawing should be marked up to reflect any minor changes. All installation notes and revisions are removed and the drawing issued as a Record Drawing.

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Drawing Signing-Off Procedure

The following images indicate the correct procedure for signing off drawings. Where drawings are issued electronically (e.g. to extranets) they must contain electronic signatures.

Prior to drawings being issued, a 'CHECKPLOT' should be printed. This plot can be either at full size or, if deemed suitable, at a reduced size. Any checkplots produced at a reduced size will be stamped accordingly so as to avoid any confusion.

The engineer responsible for checking the drawing should sign the 'Checked and Approved for Issue’ box and return the drawing to the CAD draughtsperson. Once the checkplot has been signed the CAD draughtsperson will add the electronic signature to the drawing. BailCAD has a utility which automatically adds electronic signatures to drawings. Before using this utility the engineer’s signature must be added to the database. The CAD representative at each location will be responsible for maintaining a database of engineer’s signatures.

In the event that it is impossible for the engineer to physically sign the drawing due to being site based etc, it is possible to create a checkplot in either DWF or PDF format which can then be emailed for checking. The drawing can then be checked and only when an email is received by the CAD operator from the relevant engineer clearly stating that the drawing has been checked and approved should the above detailed issue process be carried out. Finally, if the engineer has access to Autodesk Design Review, it would be possible for them to add a signature block to a DWF (see example on left) and email the mark-up back to the department.

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Once the checkplot has been signed and returned to the CAD draughtsperson he or she will add the electronic signatures. The drawing can then be issued. It is important when issuing or archiving drawings electronically that an electronic signature is added.

Note that EVERY issue of a drawing should include a revision block - this includes the initial issue at Rev 0.

Without a revision block for each and every stage of the drawings life, there is no audit trail available to trace its history should it be needed.

The names used in the ‘engineer’ and ‘checked by’ boxes should be those persons associated with the CURRENT

issue of the drawing. All previous names are recorded in the revision blocks. The ‘engineer’ and ‘checked by’ names should not be the same – the practice of self-checking is not to be used.

Every issue is to include a full signature – either hand-written or electronic.

If you attempt to run a drawing through IssuePLOT and there is not at least one revision block present on the sheets then the process will halt until this is rectified. To ease the revision process, there are a number of tools on the BailCAD ribbon panels for adding electronic signatures and revision blocks etc. These tools will be detailed further into the manual. By using the included tools, you will not only be able to work more productively but you will also ensure that all drawings are produced in a uniform manner.

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QR Codes

Drawings issued using BailCAD IssuePLOT will automatically have a QR code added to the drawing sheet. This QR code, when scanned with a compatible device, will read an online database to confirm whether or not the drawing is the latest issued version. The webpage showing the scan result will also contain a link to the issue history for the drawing. In the case of scanning a code on a CheckPLOT the user will be notified that the drawing is not an official issue and should not be used. If drawings are produced in DWF format, the QR code will contain an embedded hyperlink which will take the user to the same verification page.

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Notes

Prior to commencing any project, Project Management should seek agreement with the client, main contractor and design team for a formal process detailing the complete drawing approval process. As a minimum this should include:

Who is responsible for comment/approval of all NG Bailey drawings?

In what format are NG Bailey to issue their drawings (e.g. full size or A3 paper copies or electronic format .dwg, .pdf, .dwf, .plt)?

What are the agreed commenting and approval periods? (Including an allowance for drawing receipt and delivery. 2 – 3 weeks is an acceptable period: for NG Bailey, the shorter the time the better. Also if no comments are received in the approval period can we take this to mean nobody has any comments and our drawing status can be raised to Construction Issue?)

What wording or letters shall be used to denote approval or otherwise. A common method used is for the drawing to be given A, B or C status.

 A denotes there are no comments and the drawing can be issued for Construction.

 B denotes the drawing contains a number of comments to be taken on board and then issued for Construction

 C denotes that the drawing is poor and should be resubmitted (comments may or may not be included on status C drawings, a drawing is usually denoted C if there would be too many comments)

Who will be responsible for coordinating comments prior to NG Bailey receiving a response? (It is important to get agreement that NG Bailey will receive only coordinated comments, otherwise we can be left trying to make sense of many comments which are contradictory, and will have little chance of gaining approval of the resubmitted drawing)

Who will be responsible for resolving disputes when parties cannot agree on the contents of our drawings?

The above assumes drawings have been produced and approved/signed off internally prior to formal issue.

Archiving

It is the responsibility of the CAD operator to ensure that all CAD drawings are issued in the correct formats and stored in the correct folders as defined previously in the ‘Directory Structure’ section on page 4. The use of IssuePLOT will ensure that this is done correctly and consistently.

On completion of a project, the appropriate sections of the ‘Issued’ folder should be put onto CD or DVD and stored in an appropriate location.

A second copy of all archive discs should be kept (preferably on and off site).

The entire file server is automatically backed up to tape daily with copies retained both in and away from the office. This is under the supervision of our IT department.

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Autodesk Design Review and Redline Mark-ups

In the previous ‘Drawing Issue’ section, the use of Autodesk Design Review (ADR) by engineers for marking up drawings was touched upon. In this section we will look at how this system can be used in tandem with AutoCAD for creating a paper-free mark-up and review process. This means all mark-ups can be done via email saving time and costs.

If DWF checkplots are sent out to engineers for checking or an engineer has a copy of an issued drawing in DWF format and wishes to detail some alterations – i.e. at record drawing stage, they can utilise ADR for this process. We won’t cover the use of this software here, but concentrate instead on how the mark-ups can be used by the CAD operator.

This is only a brief overview of the functionality offered by using ADR and AutoCAD and not a definitive guide to all the functions offered.

The first step is to load the mark-up into AutoCAD. With a blank drawing open, type OPENDWFMARKUP or go to the Markup panel on the Annotate ribbon tab and select Load Markup DWF and browse to the relevant DWF markup file.

You will then be presented with the Mark-up panel which will show the drawing file tab which was used to create the DWF. You should double- click the tab name and this will open the drawing with the mark-up overlaid.

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Next, you will see a list of all mark-ups in the DWF. By double-clicking each individual mark-up, the DWG file will zoom to the relevant area for quick reference.

Once a particular mark-up has been completed in the DWG you can go back to the mark-up panel and right-click it and set its status to Done and then move on to the next area of work. By changing the status, you will be able to clearly see which have been done (note the green tick) and those which haven’t.

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BailCAD - Electrical

Electrical Symbols

Simple to understand and use symbol insertion menus. From the single slide menu, it is possible to select any symbol from all NGB libraries, set the insertion scale and the insertion level. All symbols are inserted on the ‘level’ layer and have a relevant BS1192 base layer, allowing for easy manipulation via the settings dialog above.

Create Elec Layers

A dialog driven tool with which you can quickly and easily create a standard set of layers based on the NG Bailey layering convention.

When this tool is run, the user is presented with a dialog box which lists textual descriptions of all the main service categories. When a main category is selected, a second dropdown list is then populated with all the available sub-categories. There are also options to create ‘complimentary’ layers for text, dimensions and attributes. If these options are deselected then only graphical layers will be created.

Ribbon Button:

Command: elay

The most common categories used within our industry are included in the tool and are listed in the previous ‘Electrical Layers’ section on page 19. If a specific service you require is not listed, please notify a member of the CSM Team and we will arrange for its inclusion within BailCAD.

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Settings

This dialog controls the display of layers associated with particular electrical services. Rather than working within the layer control dialog box and selecting layer names, this dialog makes the control of layers much more intuitive. To freeze the display of Small Power graphical elements, the user would simply put a tick in its associated box. To freeze either the attributes or text associated with the small power, the user simply puts a tick in either the A or T box.

The VP Layer section controls whether the layers are frozen in modelspace or within individual viewports only.

The print scale and floor level sections are used to control symbol insertion. The print scale sets the scale at which symbols will be inserted into a drawing and the floor level sets the insertion layer on which the symbol will be inserted. Symbols do not get inserted on their base layer in order that we can introduce extra levels of manipulation.

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LV Schematic

This is a simple dialog driven utility which will help to draw a basic LV schematic diagram. Obviously, it is not possible to draw a full and final schematic as the input required would be too extensive but it will provide a base building block with a consistent look and feel for all schematics.

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3. Select quantity of outgoing devices along with their associated connected device…

4. Repeat the process for all outgoing devices on bus section 1, select whether metering is required and also what types of devices feed the board…

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5. Repeat the process for bus section 2 should it be required…

6. Select whether you wish to add a life safety section and if so, how many outgoing ways it should contain

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7. Select any other options you wish to be shown on your schematic.

8. Next, add any standard notes you require. You can also add custom notation using the boxes provided.

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9. Finally, edit the Panel Reference and hit OK. Your schematic will now be compiled.

If you requested a cable schedule to be included, this will be shown alongside the diagram with rows numbered matching the outgoing cableways. This table is fully editable and columns and rows can be added, removed and formatted as required. The text shown in the description column is directly linked to the description text shown above the outgoing devices. If you edit the text in the diagram, the text in the table will change to match (after a regen). The text does not update from the table to the diagram. If you wish to have independent text, simply delete the field out of the relevant table cell.

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Hospital Symbols

NHS Estates symbol library. This section is to be considered as ‘work-in-progress’. It does not currently have any form of automatic layering and the libraries are awaiting further symbols.

Prompt For Attributes

Changes the ATTREQ system variable t prompt a user to input attribute details when inserting any symbols or blocks.

Snap To Ceiling Grid

When this setting is turned on, symbols such as smoke detectors can be snapped to insert in the centre of ceiling tiles by selecting intersection points on a ceiling grid.

Circuiting

As the name suggests, this is used for adding circuiting lines to a drawing. This can be used for linking small power, lighting, fire alarm symbols etc. The lines are drawn on the attribute layer of the symbols being circuited. Only BailCAD electrical symbols can be circuited with this tool.

Lighting Utilities

This is a suite of tools for carrying out quick lighting layouts Select Luminaire

This is used select which luminaire you wish to use in your layout. The selection can be done by either copying a block that is already inserted into the drawing, or if you know the block name, this can be entered on the command line.

Position luminaires

By using this tool, it is possible to quickly layout simple lighting schemes. The user will be prompted to select the four walls of room or area and then to detail how many luminaires are to go into each row and column. After entering the relevant information, the luminaires will be inserted in your required layout.

Position Points

If you are unsure of what luminaire symbol you will be using for a room, you can choose to insert node points instead. These can then be used at a later time for snapping your luminaire inserts to.

The following utilities were written some time ago for importing data into the Calculux lighting design package. The use of these tools now is quite limited.

Set Relative Point

A user would use this to select a setting-out point in a room or area – e.g. a corner or gridline intersection etc.

Display Co-ords

When the user has set the relative point and then uses this tool, if you select any particular luminaire in your scheme, a dialog is displayed showing co-ordinates relevant to your setting out point.

Write Co-ords to File

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BailCAD - Mechanical

Mechanical Symbols

Using the same system as the electrical symbols, this tool can be used to insert rectangular and circular grille and diffuser symbols, schematic valve symbols (which can auto-layer and cut into lines), various mechanical drafting details (cut pie-ends, turning vanes, attenuator sound waves etc) and basic heat emitters

Create Mech Layers