BIFFI IMVS2000v2 - Page 34

September 2019
Installation, Operation and Maintenance Manual
MAN720_IMVS2000v2_IOM Rev. 6
MAN720_IMVS2000v2_IOM Rev. 6
Section 5: Working Principle
Working Principle
The “SOV A – SOV B Test” can be performed by using “Manual PST” command or DI “PST CONTROL."
“PST St.” describes the result of the last “SOV A – SOV B TEST."
“M. PST Date” and “M. PST Time” indicate the date and the time of the last SOV A – SOV B Test.
If the command is received, but:
- “Cal. Status” ≠ “Passed” or
- “Base. S. St.” ≠ “Passed” or
- “B. PST St.” ≠ “Passed” or
- “Pr. S. 1-2” = “None” or
- “Al. PSA En.” = “No” or
- “Al. PSB En.” = “No”
Then:
- The command is not executed
- “PST St.” assumes the value “Conf. Err.”
- “M. PST Date” and “M. PST Time” assume the current date and time values
- The DO PST PASSED contact is opened
- The DO PST FAILED contact is closed
- The graph is not stored
If the “SOV A – SOV B Test” command is received, but:
- “Cal. Status” = “Passed” and “CAL Alarm” is active or
- “POS Alarm” is active or
- “HSP Alarm” is active or
- “LSP Alarm” is active or
- The start position is not valid
Then:
- The command is not executed
- “PST St.” assumes the value “Failed”
- “M. PST Date” and “M. PST Time” assume the current date and time values
- PSA Alarm and PSB Alarm are activated
- The DO PST PASSED contact is opened
- The DO PST FAILED contact is closed
- The graph is not stored
If a problem is verified during the SOV A – SOV B TEST execution:
- “PST St.” assumes the value “Failed”
- “M. PST Date” and “M. PST Time” assume the current date and time values
- PSA Alarm is activated if a problem is detected during the SOV A Test
- PSB Alarm is activated if a problem is detected during the SOV B Test
- The DO PST PASSED contact is opened
- The DO PST FAILED contact is closed
- A new graph is stored (the Status is “Failed”)
If the SOV A – SOV B TEST is successfully executed:
- “PST St.” assumes the value “Passed”
- “M. PST Date” and “M. PST Time” assume the current date and time values
- PSA Alarm is cleared
- PSB Alarm is cleared
- The DO PST PASSED contact is closed
- The DO PST FAILED contact is opened
- A new graph is stored (the Status is “Passed”)
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