1. PLC Coding and Local HMI
Swapnil Shrishrimal
LCLS-II Software Review
November 14, 2018

2. Charge
1. General a. Is the documentation and coding maturity consistent with schedule? 2. Equipment Protection a. Are all the equipment protections functions (in particular responses to abnormal conditions such as trips, alarms and interlocks)… traceable to PLC Code? 3. Definition and Documentation b. Is there traceability between documentation and the PLC Code? 4. Coding a. Are coding Rules adequately defined and implemented? b. Is the PLC code clearly developed, and consistent with documentation and coding rules?
LCLS-II Software Review, November 14, 2018

3. Outline Software Development Coding Rules Traceability HMI Development
Schedule
LCLS-II Software Review, November 14, 2018

4. Software Specification Developed by
Documentation
Software Specification states control philosophy for each system developed by JLAB.
Initial draft for all software specification is submitted in document control.
The 4K Main Cold Box control philosophy is developed by Air Liquide and JLAB is responsible for PLC programming.
Oil Processor was procured with PLC hardware & software.
System
Software Specification Developed by
Gas Management
JLAB
Utility
Warm Compressors
Recovery Compressor
2K Sub-Atmospheric Cold Box
4K Main Cold Box
Air Liquide
*Oil Processor
Vendor
LCLS-II Software Review, November 14, 2018

5. PLC Hardware and Software Details
System Description
Allen-Bradley PLC Type
Programming Software
Developed By
Gas Management
ControlLogix
1756-L81E
Rockwell Automation Studio5000
JLAB
Utility System
4K Main Cold Box
2K Cold Box
Warm Compressor
1756-L71
Recovery Compressor
Micro 850
2080-LC50-24QWB
Connected Components Workbench
*Oil Processor
CompactLogix
1769-L30ERM
Vendor
LCLS-II Software Review, November 14, 2018

6. Coding Development
LCLS-II Cryoplant PLC Code is modified version of running PLC code from JLAB’s CHL2 cryoplant.
General software specification (79120-C6003) states coding rules for the software development.
Sub-routines explained in LCLS-II General software specification ( C6003) are consistent in all the JLAB developed PLC codes for LCLSII cryo systems except for Recovery Compressors due to different development environment.
These sub-routines are presently in-use on PLC codes across JLAB cryo systems (CHL2, CTF, HDR, etc).
4K Main Cold Box PLC code is developed using control philosophy document provided by Air Liquide (C1303-NT-400(X) and LCLS-II General software specification (79120-C6003).
Note: Acceptance of 4K Cold Box PLC Code is planned and agreed by Air Liquide.
LCLS-II Software Review, November 14, 2018

7. Consistency – PLC Code
The JLab software is very modular, so it is easily adapted to any differences between the JLab and LCLS-II systems.
These sub-routines are tested and presently in-use at JLAB CHL2 Cryo Plant.
Sub-Routines used are explained in General Software specification and are consistent in all PLC Codes.
LCLSII Utility System
PLC Code
LCLSII Gas Management PLC Code
JLAB CHL2 Gas Management PLC Code
LCLS-II Software Review, November 14, 2018

8. Coding Rules
LCLSII coding rules are derived from JLAB’s internal coding rules.
PLC controller name is LCLSII_System,
where, System can be GMGT, Utility, SCB or MCB.
The PLC Code is divided into different tasks (Main task, Periodic_100ms task, etc).
Each task is then divided into various programs (Main Program, Cryocons,etc).
Each Program is further divided into Master routine (MainRoutine) and various sub-routines (Alarms, cPID,etc).
Sub-routines are executed directly or indirectly from the MainRoutine.
PLC Modules are configured to set the analog inputs per their operating ranges and set the outputs to know fail-safe state.
LCLS-II Software Review, November 14, 2018

9. Coding Rules
Format used to develop PLC Code is Ladder Logic and structure text.
Sub-routine naming is based on the task it’s performing (eg. All the alarms can be traced in Alarm sub-routine).
All the user-defined tags have meaningful names in PLC code.
All the IO tags have description & names per wiring drawings/software specification.
The code is well commented, such that any competent programmer could quickly discern the code’s function.
Tasks explained in software specifications can be clearly identified and traced in the PLC Code.
PIDs, Alarms, Trips, flow calculation and I/O communication structure and naming suffix are same throughout all the systems.
Some data elements are combined into arrays to minimize transfer overhead of tags between EPICS and PLC.
LCLS-II Software Review, November 14, 2018

10. Example – PLC Code IO Name Ladder Logic
IO Description
Comments
Data Arrays
Meaningful Names
IO Name
Ladder Logic
Gas Management Digital Output Wiring Drawing ( )
IO Configuration
LCLS-II Software Review, November 14, 2018

11. Traceability – General Software Specs (79120-C6003)
M. Alarms
The alarms function loads the current channel value of tag into the _Alarm structure and calls the Alarm_Evaluation function.
N. Alarm_Evaluation
All of the following analog signals will have two high alarms and two low alarms, the first set of alarms is a warning ‘yellow alarm’ and the second set is a serious alarm ‘red alarm’ and operator should take actions. All alarm set points are to be modifiable by operators. Process values greater than the Hi alarm or lower than the Lo  alarm are in a state of ‘yellow alarm’. Process values greater than the HiHi alarm or lower than the LoLo alarm are in a state of ‘red alarm’. Process values greater than the MaxRange alarm or lower than the MinRange alarm are in a state of ‘SLAC Defined alarm color’. A red alarm supersedes a yellow alarm. These alarms’ settings will exist in the software even if there is no intention to use a specific alarm setting and operator can disable particular alarm using a disable.INT tag. The setpoint tags use the same engineering units as the process variable.
This subroutine handles the alarm status of an alarm channel, and synchronizes setpoints between local (HMI) and remote (EPICS) mode as changes are made.
The channel that is being alarmed upon has to be moved into the alarm channel independently of this subroutine. i.e Alarm_Evaluation subroutine should be called in alarm routine.
This subroutine compares the channel value with their corresponding setpoints and generates an integer.
( Lo=0, LoLo=1, NoAlarm=2, Hi=3, HiHi=4, MaxRange=5 or MinRange=6).
This subroutine also latches the alarm if the HiHi, LowLow alarm is active for longer than the latch time.
Reset will be required to clear the latch but alarm integer gets cleared once the alarm is ok (i.e auto reset of alarm).
Hi, Lo, HiHi, LoLo, MaxRange, MinRange alarm setpoints should be displayed on the alarm screen
LCLS-II Software Review, November 14, 2018

12. Traceability – Gas Management Software Spec (79120-C6002)
Description
Tag
Min Range
Lo Lo Alarm
Lo Alarm
Hi Alarm
Hi Hi Alarm
Max Range
Mass Out temperature
CTP21040
0.0
270.00
275.00
320.00
325.00
400.0
Mass Out pressure
CPT21040
6.30
8.00
15.00
18.50
28.0
Storage Pressure
CPT21030
5.00
6.50
13.00
AMB HX temperature
CTP21000
250.00
350.00
370.00
MPH-MP Bypass pressure
CPT21032
1.00
3.00
6.00
14.0
Low pressure
CPT21012
1.02
1.20
1.25
7.0
High temperature after final oil removal
CTP21042
Medium pressure
CPT21022
1.05
2.50
2.80
HP CBX temperature
CTP21045
MP CBX temperature
CTP21025
LP CBX temperature
CTP21015
Cooldown pressure
CPT21005
0.75
0.85
1.30
1.50
AMB HX pressure
CPT21000
0.95
1.65
Primary CW Return
CPT86046
1.0
2.0
3.0
3.5
8.0
Primary CW Supply
CPT86036
2.5
Disable
Primary CW HX
CPDT86038 .5 1
100.0
Secondary CW Supply
CTP23410
300.0
310.0
Secondary CW HX
CPDT23406
Secondary CW CBX
CPDT23420
1.5
Secondary CW Filter 1
CPDT23411
Secondary CW Filter 2
CPDT23412
LCLS-II Software Review, November 14, 2018

13. Traceability – PLC Code
Alarm Evaluation is performed here.
LCLS-II Software Review, November 14, 2018

14. Traceability – HMI Local Touch panel Remote EPICS
LCLS-II Software Review, November 14, 2018

15. Adjustments required during Commissioning
PID loop Set points are initially chosen from JLAB’s CHL2 cryoplant.
These setting will be entered in PLC and operator will be able to make changes as required.
JLAB has requested Air Liquide to provide 4K Cold Box PID loop settings.
Operator can make these changes from HMI (Local/Remote) or from PLC Code.
LCLS-II Software Review, November 14, 2018

16. HMI Hardware and Software Details
System Description
HMI Type
Programming Software
Developed By
Gas Management
Allen Bradley
2711P-T15C22A9P
FactoryTalk View Studio
JLAB
Utility System
4K Main Cold Box
2K Cold Box
Warm Compressor
2711P-T15C4A8
Recovery Compressor
Automation Direct
EA9-T8CL
C-More
*Oil Processor
2711P-T7C21D8S
Vendor
LCLS-II Software Review, November 14, 2018

17. Local HMI Development Rules
Local HMI provides option to operator to make changes to system during EPICS outage/breakdown.
Operator must select local mode if he/she desires PLC to take actions from local touch panel.
Essential system tags like PID loop, Alarms, Start, Stop commands are available to operator from touch panel.
HMI displays are developed using available HMI displays/EPICS screen at JLAB so that they replicate P&ID’s.
PLC Input tag Suffixes or structure are separate for HMI and EPICS. PLC synchronizes all the tags between HMI and EPICS when change made from either is reflected on other display.
LCLS-II Software Review, November 14, 2018

18. Traceability - Local HMI
LCLS-II Software Review, November 14, 2018

19. Traceability – P&ID (79120-0002)
LCLS-II Software Review, November 14, 2018

20. Is the documentation and coding maturity consistent with the schedule?
System
PLC - Draft
Local TouchpanelHMI
Start
End
Warm Compressors
2017
May 2018
Jun 2018
Gas Management
Apr 2018
Utility
Nov 2018
Jul 2018
4.5 K CB
Aug 2018
Feb 2019
Oct 2018
Dec 2018
2 K CB
- Refer Scope, Requirements, Deliverables & Schedule talk
LCLS-II Software Review, November 14, 2018

21. Potential delays in the schedule
CAN communication for 2K Sub-atmospheric cold box – (under development/testing expected to be ready by Dec 2018)
4K Main Cold box Control Philosophy (Air Liquide Scope – initial draft developed on Nov 27th,2016)
JLAB suggested corrections and meeting was held between JLAB, SLAC and AL on Sept 27th,28th 2018.
Revised document received on Nov 12th, 2018.
Bench Testing software fixes.
LCLS-II Software Review, November 14, 2018

22. Charge Addressing
1. General a. Is the documentation and coding maturity consistent with schedule? YES 2. Equipment Protection a. Are all the equipment protections functions (in particular responses to abnormal conditions such as trips, alarms and interlocks)… traceable to PLC Code? YES 3. Definition and Documentation b. Is there traceability between documentation and the PLC Code? YES 4. Coding a. Are coding Rules adequately defined and implemented? YES b. Is the PLC code clearly developed, and consistent with documentation and coding rules? YES
LCLS-II Software Review, November 14, 2018