How should I wire two power supplies to mains

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I have two power supplies I need to connect to mains.

One is an Abletec +-54v that is powering my amplifier and the other is 12v and powers my preamp.

I currently have an spst switch wired between the mains and the Abletec. It is working. I intend to replace that with one of those fused switch IEC connector (like this) and rewire it using 12-10AWG crimp connectors.

How should I wire in the second power supply?

Thank you for your help!
 
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How should I wire in the second power supply?

It's best to use a separate fused IEC for each unit, with appropriate size fuses for each.
If you want to use only one power cord and IEC socket, fuse it for the amplifier,
and then still use an additional smaller fuse for the preamp supply, connected
in the hot lead to the 12V supply input. Otherwise, the 12V supply could have a problem
without blowing the larger fuse in the IEC socket.
 
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If I wanted only a single power cord, how would I wire the second power supply?
It seems like a bad idea to crimp two wires in a single connector and repeat that three times (load/neutral/ground). Are terminal blocks a bad idea?

You are right, crimp only one wire per fast-on terminal of the IEC. Never use more than one wire
in a fast-on crimp terminal, it will not be reliable or safe.

There would have to be a jumper from the IEC hot (already fused) terminal to an isolated terminal.
Then two more wires connect to the isolated terminal: the amplifier's hot supply wire, and the wire
going to the hot terminal of the fuse holder for the 12V supply's hot input. There are isolated,
chassis-mounting terminals that you can buy, like terminal blocks. Those are usually rated for 300V.
 
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I was thinking of this terminal block

That should be fine. The rule with such terminal blocks is: no more than two lugs per screw.
So, connect the IEC wire (with a crimped on ring lug) to one side, and the two output wires
(each with a crimped on ring lug) to the screw on the other side. On the output side,
turn the bottom ring lug upside down, so the two barrels don't interfere with each other
when bolted together. Of course, use insulated crimp on terminals for this application.
 
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