60 VAC/VDC rating on contacts 2

[bacon4life]

I was recently assigned to install an oil/water sensor and a normally closed valve that the oil sensor holds open.

The cut sheet says the dry contacts are good for 60VAC/DC. Is this a common rating? I know SCADA often uses 24 or 48 VDC, but what type of application uses less than 120 VAC?

Now instead of just one 120VAC circuit with the 120VAC sensor, a 120 VAC interposing relay and the 120VACmotor operated valve, I will also need a 48VDC circuit run to the oil sensor.

 

[itsmoked]

That does indeed BLOW.

Those ratings are for the SCADA PLC realm.

I would've expected something up for 60VDC to handle 120VAC without a problem. Not this time though.

Are you sure the oil sensor can't run on 12 or 24VDC - something you are likely to have available?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[bacon4life]

Unfortunately the both the valve and the oil sensor are 120VAC. I do have 48 VDC available on the site, it just means pulling another circuit and making it a bit more complicated than I had hoped.

 

[jraef]

Most likely it is an IEC designed device for use where the most common control voltage is 24VDC. Here in N. America we have not adopted that as a standard yet, but with the continued influence of IEC control components such as this, as well as the new Arc Flash ratings and SCCR issues, we will begin to see it a lot more often.

Get used to it.

JRaef.com
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