Chapter 09 Profibus PLC Prog

PLC-

Programming

PLC profibus connection

for

Inhalt

2.5 Description of initialisation parameters ... 8

2.6 Used blocks ... 9

2.7 Standard communication PLC DP – AST30 ... 10

2.8 Functions that can be controlled via profibus DP ... 11

1

General

Profibus connection for AST30 sequence controller offers the possibility to start the single screwdriving sequences and to download final values and parameters of the screwdriving cycle to the plc.

All needed software is available in the software package DEPRAG_AST30.zip.

2

Connection

2.1 Wiring

Profi-bus has to be connected with connection GX8 (Baud-Rate: 1,5 MBits) of AST30 controller (see chapter 7 of the handbook: Controller AST30 - Hardware Description)

Additional pin 14 (emergency stop) on connection GC30 has to be connected to 24V.

To use profibus special device data has to be loaded to the AST30 (DEPR_DP.ngd).

Please refer to LOADER manual.

2.2 Hardware

To connect AST30 to a Siemens S7 the following steps are necessary: - Unzip of software package DEPRAG_AST30.zip.

- Insert GSD-file

- Installation in hardware

2.3 Software

For controlling AST30 by Profibus the following blocks are needed. All blocks are keeped in the archive.

In the instance-DB all values are filed and can be monitored as well.

DB110.DBD 218 "DB_AST30_1".Cycle Cycle counter R10 Floating point DB110.DBD 222 "DB_AST30_1".Status Status of screwdriving cycle R11 Floating point DB110.DBD 226 "DB_AST30_1".Variante Program number R12 Floating point DB110.DBD 230 "DB_AST30_1".Section Step, in which final values have

been saved R13

Floating point DB110.DBD 234 "DB_AST30_1".Torque Final torque R14 Floating point DB110.DBD 238 "DB_AST30_1".MAX_Torque Torque upper limit R15 Floating point DB110.DBD 242 "DB_AST30_1".MIN_Torque Torque lower limit R16 Floating point DB110.DBD 246 "DB_AST30_1".Angle Final angle R17 Floating point DB110.DBD 250 "DB_AST30_1".MAX_Angle Angle upper limit R18 Floating point DB110.DBD 254 "DB_AST30_1".MIN_Angle Angle lower limit R19 Floating point DB110.DBD 274 "DB_AST30_1".T_Torque Shutoff torque R24 Floating point DB110.DBD 278 "DB_AST30_1".T_Angle Shutoff angle R25 Floating point

2.5 Description of initialisation parameters

identifier type data type meaning

Modulnum INT profibus address - 3

Modul_Adr_in WORD from HW-Config W#16#100 à address 256

AST30_START BOOL start signal for AST30

AST30_STOP BOOL stop signal for AST30

INSTANZ_DB_NR

input

INT number of instance-datablock

PRG_NR DINT program in AST30, that is to be started

INIT_OK BOOL initialisation finished

AST30_OK BOOL screwdriving cycle OK

AST30_NOK BOOL screwdriving cycle NOK

AST30_READY BOOL AST30 ready for new screwdriving cycle

AST30_BEREIT

output

BOOL AST30 ready

AST30_DATA_OK BOOL AST30 Data read

2.6 Used blocks

functions and functionblocks

FB 111 DATA_READ Receive and analyse data FB 112 DATA_WRITE Compile and send data

FB 113 COMMAND Accept commands and parameters FB 114 INITIALIZE Adapt output data to input data FB 116 ERWCMD Parameters via expanded protocol FC 107 LREAL_TO_REAL Convert LONG to REAL

system functions by Siemens

SFC 104 DPRD_DAT read DP-slave SFC 15 DPWR_DAT write DP-slave

2.7 Standard communication PLC DP – AST30

1. deposit value for program in double PRG_NR 2. Request AST30_BEREIT

3. Request AST30_READY

4. signal high to input AST30_START

5. Request AST30_READY, AST30_OK and AST30_NOK 6. Request AST30_DATA_OK

7. signal low to input AST30_START

At program-start, the signals “Ready” as well as “OK/NOT OK” are set on LOW-level. The subsequent high-level of OK as well as NOT OK signalizes the end of the screw driving cycle.

Signals OK-Cycle

2.8 Functions that can be controlled via profibus DP

Command 37, start screw driving cycle

This command starts a screw driving cycle. The parameter contains the

number of the program which is to be executed. The output stage is activated during the command (CNC_ON = 1).

The command will only be executed, if

-- the AST30 is in the operational mode AUTOMATIC (CNC_RUN = 1)

The command is finished, if

-- the process has been terminated completely -- a malfunction has occurred

-- the command has been aborted (CMD_BYTE = 0)

Command number

CMD_BYTE = 37

Call condition

CNC_RUN = 1

Call parameter

CMD_PAR = byte 7 = variant number

Return value during the execution

CNC_PAR = depending on the firmware and application

Return value after finishing the command

CNC_ERR = 1 -> error

CNC_SB2 = CNC_ERR = 1 -> error code, CNC_ERR = 0 -> message code CNC_SB3 = last or faulty section

CNC_PAR = depending on the firmware and application

Command 39, finish screw driving cycle

This command finishes a screw driving cycle. The parameter states if final values are to be generated.

the command (CNC_ON = 1).

The command will only be executed, if

-- the AST30 is in the operational mode AUTOMATIC (CNC_RUN = 1)

The command will also be executed, if An error occurs (CNC_ERR <> 0) The command cannot be aborted.

Command number

CNC_BYTE = 39

Call condition

CNC_RUN = 1

Call parameter

CNC_PAR=0 -> abort screw driving cycle Return value during the execution

CNC_ERR = 1 -> error

Return value after finishing the command

CNC_ERR = 1 -> error