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Sevcon Gen4 keyswitch/fuse rating?

4903 Views 0 Replies 1 Participant Last post by  MalcolmB
I'm busy gathering parts to rebuild my classic Mini, based around a Motenergy ME1616 motor and Sevcon Gen 4 Size 6 controller. I want to make sure I get all the safety aspects right, so I'd just like to check with you knowledgable folk that I'm choosing the right fuses and relays.

The Sevcon wiring diagram shows the key switch connected via a fuse to the positive side of the traction pack. The controller takes care of precharge and closes the main contactor when the capacitors are fully charged. This means that the control fuse and key switch should carry full pack voltage (in my case ~115V). According to the Sevcon manual the control fuse should be rated for 3A, to power the contactor coil and line circuits.

I don't want to have pack voltage at the ignition switch, so I need a suitable 12V coil relay to close the key switch circuit from the ignition.

My question is am I right in thinking I need a relay rated for 120V/3A or better? And if so, can you recommend a suitable high-voltage, low-current relay, preferably not too bulky? I've been looking around and the closest I can find are reed relays, but they seem quite pricey.