SIS system relay failure
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What kind of message is displayed in the SIS system when a relay failure occurs? Can a relay failure in the SIS system cause the system to stop operating? Does anyone know what this alarm means?
Relay failures cannot be detected by the SIS system. There are two types of such failures: one is a loss of power to the coil, in which case a spare contact that is not used by the relay can be connected to the SIS’s DI card to trigger an alarm. If the relay operates erroneously due to normal contact issues, this cannot be detected. To prevent such failures, it is advisable to replace the relays with those that have a longer service life during maintenance
Relay failures are caused either by a power loss or by problems with the contacts. Choose high-quality relays.
All DO safety relays have their coils always powered; it is necessary to check the state of the relay coil when the DO output is at 0 and the machine stops. Some manufacturers’ safety relays provide a signal for coil failure, which can be fed back to the SIS for alarm purposes.
It will stop if there is a chain. Switch to forced enforcement promptly; make the switch