Miller Spectrum 875 Auto-Line Internal Torch Wiring

Does anybody on here run a Miller 875 on their Langmuir table? I am wondering how you have your torch-fire wired up. I have mine spliced into the switch wires from the torch, but this isn’t the “proper” way. Miller shows two spots to wire into. One with 24v live terminals, and one with cold terminals. RMT1 and RMT2. The manual shows how to hook up a torch fire with the factory automation kit installed. Mine does not have the factory kit installed.

Using the spliced method, the torch has a second or so of pre-flow before starting the arc. Making it very difficult to program the right pierce delay times. I’m hoping that tying into the factory location, the torch will fire sooner?

I had a 375 Extreme running on it previously, but the 375 would fire right away when commanded to do so by mach3.

Any productive help would be appreciated!


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Ok, seems nobody had any input, so ill leave this here for the future if anybody needs it. NOTE: this is an ICE-60T torch on a Miller Spectrum 875 Auto-Line

There are two ways for the Langmuir to fire the torch on the Miller 875.

The easiest way is to tap into the wire labelled 13 and the wire labelled 14, connect to the wires from the table, in any order. Done (Notice wire and tap location in the bottom right corner of image)

The PROPER way, according to Miller, when using a handheld torch in place of the miller machine torch, is to remove the trigger micro-switch in the torch - Install a 23.7 K Ohm (24K) resistor into the connector.

Then get one of these square connector housings and pin for about $4 and crimp terminals onto two wires and install in the bottom two positions. (Position 1 & 2, labelled on the board for RMT1)
Note in the picture the two black wires installed into the connector and inserted into RMT1.

Then the two wires from the connector get routed to the wires from the table, and you’re done.

Now, after trying and testing both methods, I have resorted back to the basic wiretap on wires 13 and 14, so I could keep the trigger switch installed so we can use the torch by hand if needed. Pre-flow is the same with both methods.

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Thank you for the info i have an 875 and a machine torch and am still in set up and wiring mode! Have you been pleased with the 875 so far?

Mclovin, I opted for the Miller automation kit, should i plug its harness into RMT1? I will be using a machine torch.

Did your system fire the torch with the machine torch and plugging into rmt 1? I am having issues with mine wanting momentary switching to fire and not a closed circuit like the Langmuir provides…

Craigg, Would you believe, I still haven’t put my machine together yet? It’s all there, just don’t ever seem to find the time. Sorry I could be of no help to you.