Download AS01023G-01, ECM2 with IEC61131-3 Functionality

ECM2 User Manual Rev. 1.5
7.9.3
User Relay Diagnostic Test
The programmable Interlock has self-diagnostics features that can diagnose internal circuit failures while in
operational mode. This is achieved through the 1oo2 topology of the design.
Each output channel has two Relays connected serially such that if one fails to open (safe state) the other will
back up.
These Relays are not diagnosed by the design for a case of contact fail to open. They need be tested once a
year in order to comply with the SIL-3.
This test is supported by a dedicated circuit that is part of the Programmable Interlock design and requires
human activation.
7.9.4
Proof Test
Proof Test Interval: Every 12 Months.
For certain industries, the maintenance of IEC61508 SIL3 certification requires that this proof test be
performed yearly.
7.9.4.1 Proof Test Definition
The periodic test should include short circuit test on output relays, transistor switch test, and input connector
short circuit test.
7.9.4.2 User Test Procedure
1. Turn off the power to the unit.
2. Disconnect all DI/O cables from connector’s panel.
3. Remove the cover on the side panel as illustrated in the following figure (Layout of I/O connector for illustration
purpose only, they may differ between systems).
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