SEGMENT DESIGN

13.6.1 Segment Topology and Redundancy

13.6.1.1 All segments shall have redundant H1 interface card and redundant fieldbus power supply (FPS). The redundant interface cards and power supplies shall be installed in a hot-swap architecture.

13.6.1.2. Cable routing shall consider maximum trunk integrity and protection against hazards. Routing design shall be submitted to PETROBRAS approval

13.6.2. Bulk Power Supply (BPS) and Fieldbus Power Supply (FPS)

13.6.2.1. BPS is general power source and provide power conversion from 125Vdc to 24Vdc. FPS is a special power source designed to feed Foundation Fieldbus segments.

13.6.2.2 Segments shall be fed by redundant BPS.

13.6.2.3. Both BPS and FPS shall have over current protection.

13.6.2.4. FPS shall provide isolation from BPS and impedance matching for the segment.

13.6.2.5. FPS shall be sized so that the minimum allowable voltage drop in a segment device shall be 11 VDC.

13.6.2.6. Status indication of the power supply shall be available on the supervisory system.

13.6.2.7. Sizing of segment power supplies shall comply with the items below:

a) full segment power load;

b) short circuit fail at one spur;

c) excess of 25% current load above the previous items, considering the segment with the highest current load.

13.6.3 Voltage Drop Checking

13.6.3.1 All segments classified as level 1 or 2 shall have a detailed calculation sheet for voltage drop.

13.6.3.2 The other segment length shall be tested according to the equation below.

L => Segment length, in meters Vc => Voltage at FPS output, in volts

Vd => Minimum allowable voltage drop on a field device, in volts Isc => Limit current for short-circuit protection, one device, in ampères

It => Segment total current minus the value for the lowest consumption device, in ampères R => resistance per cable length, in ohm / kilometer

In the case of equation in item above is violated, a detailed calculation sheet for the segment voltage drop shall be generated to verify minimum allowable voltage drop.

13.6.4. TERMINATORS (T)

13.6.4.1. Terminators shall be located at the each end of the longest run of the trunk cable.

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*

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* (

1000 R It Isc

Vd L Vc

+

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13.6.4.2. In case no disturbance is observed in communications, terminators may be internal to FPS.

13.6.5. Segment devices and Function Blocks

13.6.5.1. The main Link Active Scheduler (LAS) shall be configured in the H1 interface.

13.6.5.2. Backup LAS shall be configured either in the redundant H1 interface when available or in a fieldbus device of the segment. The device shall have only monitoring function in the segment.

13.6.5.3 In case a monitoring device can not be chosen, backup LAS shall be configured in the segment device with the most available bandwidth (fewer function block external links).

13.6.5.4. All function blocks in a control loop shall be in the same segment. Deviations from these criteria shall be discussed with PETROBRAS.

13.6.5.5. Function blocks involved in control loops shall be configured as standard FF blocks. Any proprietary function block or parameter configuration must be submitted to PETROBRAS approval.

13.6.5.6. When the design consider the PID block running in the field device, the PID blocks shall reside in the final control device. In case of simple cascade PID control, if PETROBRAS accept a final control device without two PID blocks available, the slave controller shall reside in the final control device and the master in the primary control loop transmitter.

13.6.5.7. When the design consider the PID block running in the field device , similarly, for a single PID control plus an override control, the override PID controller may reside in the transmitter of the restriction variable.

13.6.5.8. When the design consider the PID block running in the field device , for split range control, the PID block shall reside in one final control device. The second final control device shall communicate with the PID block in the first one.

13.6.5.9. Valves shall be driven to last control position in case of communication malfunction, unless process conditions require otherwise.

13.6.5.10. Valves shall be driven to fail safe position in case of power supply failure and shorted segment.

13.6.5.11. There shall be a maximum of 10 devices per segment, including at most 2 control valves. This requirement shall hold, unless it conflicts with control loop performance as stated below.

13.6.5.12. Segments with only monitoring devices shall have neither redundant H1 interface nor LAS in field device.

13.6.6 Function Block Tagging

13.6.6.1. Function block tag shall follow the pattern below.

DEVICETAG FUNCBLCKTYPE INDEX Examples: FT202_AI_1, TT110_PID_2 13.6.7. Segment Scheduling

13.6.7.1. Unscheduled communication time shall not be less than 70% of the macro cycle. Unscheduled time availability shall be verified for all segments.

13.6.7.2. Macro-cycle frequency shall be at least 3 times the frequency response of the process.

13.6.7.3. A calculation sheet with segment scheduling shall be provided for each segment. The calculation sheet shall include function blocks execution time, as well as scheduled and unscheduled time sizing criteria.

13.6.7.4. It shall be possible for the user to configure the macro cycle.

13.6.8. Control Performance

13.6.7.1. The following periods shall be considered for maximum control response time:

Process Variable Maximum control response time Flow 1000 ms

Pressure and Differential Pressure 1000 ms Temperature 3000 ms Level 3000 ms Analytical 3000 ms Fast process 150 ms

Note: These values can be modified due to technology licensor requirements.

13.6.8.2. The macro cycle shall be discussed with PETROBRAS during detail engineering for each H1 segment. The response time shall be considered according to the diagrams below for each case, control in the field or in the host. Deviations from specified performance shall be discussed with PETROBRAS.