Spectrum 300 circuit board

[Mglanton]

I recently had my main board repaired by York electronics. Like a dummy, I didn't take a picture of the connectors before I disassembled it. Would someone please send me a picture of the main board with the connectors on it. I have two areas I am concerned about, lower right corner of the board has two identical female connectors however I only have one connector on the harness. Also there is a 14 pin female connector more or less in the center of the circuit board that I don't find a connector on the wiring harness. Any help is much appreciated.

[Aeronca41]

Looks like no one who has one has seen your post. If you look in your manual at the wiring diagram, the wires are all numbered and seem to show what connector and pin they go to. May be your best bet if no one responds. You might also call Miller tech support and ask for help-they will probably lead you through it over the phone. Great people there.

[Mglanton]

Problem is I don't have a manual and the ones listed under the tech library don't show a picture of the board or the harness. If no one bails me out of my snafu I'll call Miller.

[Aeronca41]

You might try posting over on weldingweb.com. It is a much broader site with more people. I personally like this Miller site because it stays focused, but maybe someone there has a 300. I suspect your machine is not nearly as common as some others, probably the reason for the lack of response.

[duaneb55]

You can download your unit manual here:

https://www.millerwelds.com/support/manuals-and-parts

Use your machines' SN to select the appropriate one.


The circuit board should have the individual board mounted receptacles identified next to each one as RC1, RC2, etc. Using your manual, identify the wire numbers going to each receptacle to determine which one is which in the harness.

[Mglanton]

Thanks for the response. There is a printed schematic on the inside of the machine and was able to get it wired with what you said shedding a light. The schematic even gave the number of plugs..