What are the risks involved in using same power supply for powering system and field in an AC800M HI based system?
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Hai,
Its not advisable to use same supply for PLC and Field IOs.A lot of things can go wrong in the field side, the most common cases are wires getting short with the ground, so when using same power supply, such circumstances may lead to PLC module failures.
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Generally 2 things influence proposed power supply for safety solution: SIL and availability.
Greeting
the most common risk for using one power supply for both the controller and the field devices , is to lose the controller supervisory in case of any malfunction occur in the field side which effect the stability of the power supply .
Normally you need your controller to be active in all time
Hello,
Find here with reply from our sales support colleague,
"Separate power supply for system and field equipment is not required from safety (SIL) reason. However, we would like it to be separate for below reason (as documented in AC 800m controller Hardware manual
3BSE036351-510)
We once again advise to follow the recommendation.
Regards
Vineet Kumar Gupta"
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