Omni8/16C/Omni8P User Manual
UMC1480R24.pdf
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© Omniflex 2021
7.6
Proof Test
Two tests of the unit are described in this paragraph (refer also to Test Functions section):
Circuit test
Proof Test
Test – pressing the Test button performs circuit test and if all internal checks pass then the unit
illuminates all lamps to check that alarm window illumination operates correctly. If one of the checks fails
the unit enters the “marching sequence” and then displays an error code. See Test Functions section 6.3 in
this manual for further details. It is recommended that this is performed daily or at the intervals no greater
than MTTR (begin of shift).
Full Proof Test is conducted once a year and requires activation of input contacts for safety-critical alarms
to simulate Alarm condition. The following test steps must be performed to conclude that the unit
operation is failure-free:
Only perform the test when no abnormal (alarm) conditions exist and plant safety is not affected by the
testing.
Isolate the unit from outputs so that it can be tested without disturbing the rest of the plant.
a)
First perform the manual Circuit Test by holding down the Silence button and pressing the Test button.
The unit will start the “marching sequence” (all windows flashing consecutively in order 1-16).
b)
After one marching sequence is completed, stop it using Acknowledge pushbutton. Omni16C
operation will revert to normal. Continue if there were no error indications.
c)
Open the circuit for alarm input under test (number of inputs depending on application).
d)
Only the correct Alarm window must be flashing.
e)
The flashing as well as the functions of Silence, Acknowledge and Reset buttons must correspond to
the sequence selected.
f)
Operation of General Alarm relays must correspond to the sequence selected.
g)
The Watchdog contacts must stay closed during the entire duration of the test.
h)
Close the input contacts (input testing is finished at this point).
i)
Change configuration DIP-switches so that both switches have only position 2 ON and others OFF. The
change must cause a unit reset and the “marching sequence” to start.
j)
After one marching sequence is completed, stop it using Acknowledge pushbutton.
k)
Change DIP switches back to the original alarm sequence. The change should again reset the
Omni16C unit. The marching sequence may or may not start at this point, depending on the alarm
sequence selection.
l)
This completes the Proof Test procedure.
