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Questions relating to designing PCBs
By ti_chris
#187552
I'm currently designing an HVAC PCB board and I'm having a hard time finding the right terminal that works for the wires. The board is designed to work directly with the HOT line from an HVAC (24VAC) and it can tolerate a current of up to 20A (apparently some machines chew up quite a lot of power). Now I'm looking at choosing the right terminal blocks to hook the wire onto the PCB board, but I can't really seem to find something reasonable.

I found the following https://www.phoenixcontact.com/online/p ... usen&tab=1 which is rated for 24A, but then the UL, cUL listings put group B @ 20A, but group D at 10A. I'm not sure what's the difference between the 2 groups. That said, CSA approval sets it to 10A. They're all rated for 300V.

I'm wondering if I'm not sizing it too high. ie: Because the ratings set this to >= 10A/300V and I'm operating on 24V, can I get a lower-rated terminal? ie: Is it more about Wattage than true voltage & amperage?

Thanks,
Chris