Had to replace some wiring to power my kings compressor and not sure if I have the +  &. - the right way. Do not want to pull it apart again to check so question is.

Using the old volt meter is it possible to check the Aderson plug without a power supply.

Cheers Robert.

Having had a look at some (internet) material where people "improve" the Thumper Max compressors, the short answer is no, not really.

The unit has a control PCB that appears to be a soft-start relay/solenoid as the unit runs at about 90 Amps, so the in-rush current will be something over that.

I imagine the fairly light weight cables on the unit get quite hot!

It would be worth pausing to consider if the Andersen connectors are the correct rating - the usual suspects are 50 Amps which may be under gunned for the application.

Forgive the quality (and sexism) of the presenter but this video will give you and idea of the current draw and some of the potential pitfalls. (I do not understand why he wants to remove the soft-start but he's the one with all the gear - and no idea!).
https://youtu.be/h2sGKHKqpNk