Hobart 27i Any tips?

FINALLY got my Crossfire pro -assembly this weekend! Been waiting on this thing for nearly 4 months…ready to get going. Gonna use my Hobart 27i and haven’t seen anything on wiring it up to the THC & table. Any tips/Gotchas? Am Nervous about the software - Fusion 360 kicked my @$$ so I’m using QCAd - and plan to get and learn sheet cam next week. Any info at all will be appreciated. New to the CNC thing.

Did you get the 27i to work? I have one and can’t get it to fire with the Crossfire software.

Search Miller 375x wiring. Its the same as the Hobart 27i.

RC1-3 and RC1-4 are the trigger and the pictures shows were the wires hook up for the THC.

Yes I did.

It works great. However, I learned that I must have everything hooked up, (Langmuir cable to computer, power cord to Langmuir box, etc.) BEFORE opening the Fire Control App.
IF everything isn’t hooked up and powered up (on the Langmuir side) the plasma will not fire. Occasionally, the table motors will not move either. Here’s my steps:
1)Turn on the computer – ensure Fire Control App is not running.
2) Turn on the Power to Langmuir Box
3) Open the Fire Control app. Once booted, check the table responds and the software DRY RUN switch not selected on.
4) Fire up plasma machine with power and air
5) Run the Z axis all the way up…then down. I learned that the switch on the Z axis gantry also controls the firing- so I run it up to make sure it is reset.
6) Verify live voltage is showing on the Fire control app. You should see this once you turn on the Plasma cutter. If no live voltage is showing on the Fire Control app, it won’t fire. At least mine won’t.

Hope this helps


Thank you for the information. I got my system to work and cut my first project.

Thanks & take care,

Did you have any luck on wiring your THC to your 27i? us got ours and we are in the same boat. Just a little confused. Do you have pics of your wiring? Thanks for any help!

Do you have any pics of the wiring? We are still having trouble. Thank you!

Since George has said that the Hobart 27i and the Miller 375X are the same machine, here are some threads related to wiring the Miller 375X.

This thread has pictures of which wires to tap for firing the torch.

This thread has pictures of where to connect the Raw voltage wires for the THC.

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