What do you guys use for connectors at any voltage over your standard single phase voltage?.
Here we would use sockets that look like this:

4-pin, 20A, 500V socket:

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Usually used for 3-phase Delta loads.

5-pin, 20A, 500V socket:

[Linked Image]

Used for 3-phase Star loads.

Unrelated, but here is a single-phase appliance inlet:

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