tingxing

Omron safety relay G7SA - output NG

6 posts in this topic

Hello, 

I am using Omron’s safety G7SA to relay 24 volt line.

But the strange thing happening is that, one relay’s output is only 5 voltage,

even the relay is on. I exchanged relays, it remains the same. Maybe the base socket is problematic? 

Or is this just G7SA failure? 5v (exactly 4.96v) is strange.

Please give me some advice.

 

Many thanks in advance.

 

Ting

 

 

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if the contact is open, then side not connected to supply will float and any voltage is possible.

if contact or socket is damaged, results can also be pretty much anything.

for more details please post exact circuit and test method 

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Thank you very much for the advice.

This relay is being used together with Omron's safety PLC, G9SP.

I am also wondering, if my logic is something wrong.

This symptom happened after the circuit had been being used for quite several weeks.

Then suddenly...

I try to extract the circuit for a clear check purpose.

 

Ting  

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well, what is the type of the load, what is the current? i used it a lot.

btw. this is a safety relay with six contacts but contact rating is rather low.

in other words it is suitable for interfacing and making hardwired logic but not very good for driving loads. and even light loads could be too much if those loads are inductive and without proper suppression. that wears contacts rather quickly. one of the problems with using suppression is that response times are lower and that is one thing one tries to avoid in safety circuits.

 

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The safety relay is supplying 24V power line for CC-Link modules, and Emergency Stop circuit.

 

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cause of the problem might has been clarified:

      too much current is found to be flowing through the safety relay - a calculation mistake, we should have chosen a relay type of higher specification.

To clear the problem, we changed the relay to a contactor.

 

Many thanks for the helpful suggestion.

Ting

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