I was going through DPDT configured electromechanical relay specifications and came across contactor current per pole. The contactor current for that DPDT relay was mentioned as 1A per pole. So, exactly what is that contactor current per pole, and how does it differ from the usual current rating of relays?
It would help if you posted the specifications and the exact model of relay or contactor you're asking about. The term 'contactor current' is generic enough that there are multiple possibilities as to what it might mean.
It was not a datasheet but just a requirement from a customer (and the customer won't reveal more information ). The requirement was:-
a)28V Electromechanical Relay (Make: STPI/Leach/Teledyne or equivalent relays)
Configuration: DPDT
Contactor current: 1A per pole
Type: Latch
b)28V Electromechanical Relay (Make: STPI/Leach/Teledyne or equivalent relays)
Configuration: DPDT
Contactor current: 1A per pole
Type: Non-Latch
OK, you simply don't have enough information to specify a relay.
"Contactor current" here appears to have no specific meaning, just that the relay contacts are rated for 1 amp. But that doesn't tell you what voltage the contacts need to be able to break. Typically the contact ratings for a relay will include the current, the voltage at AC or DC (or both, usually with different numbers) and often the load type--resistive, inductive, etc.
Also, as already stated, if the "28V" refers to the coil voltage, is it AC or DC?
And 'latch' is also incomplete as there are multiple ways a relay can be configured to latch. I think the most common are single-coil set/reset where it changes state with each input pulse and dual-coil set/reset which should be self-explanatory. But there are others setups as well.
Good luck with your customer.