Contactor contact voltage rating datasheet confusion

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Joined Jun 25, 2019
Hi, I'm working on an electric car project and need to choose a DC contactor to use with a emergency shutdown switch. The one I am looking at has the datasheet here (product number: 70-902):

I am dealing with a peak current of 60 A and a 48 V nominal (54 V peak) battery voltage. In the datasheet, under "contact rating" the voltage specified is the same as the coil voltage (12 V) which seemed low to me when I bought it, and I thought that this value was actually the coil voltage under these max current conditions as underneath, the "breakdown voltage" is 500 Vrms at 60 Hz. However I am now not sure what to think and maybe the rated contact voltage actually is 12 V and the "breakdown voltage" is the max voltage once the circuit is open. Could someone clarify what this means? Thanks a lot!


Joined Jul 18, 2013
The breakdown voltage is the insulation value.
Which means in theory you can switch higher than 12vdc on the contacts, the coil itself is 12v.
See the derating chart for the contacts, I see no reason why you are limited to 36v
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