Plasma cutter unit turns on and runs, but when you pull the trigger there is an audible click from the unit and no electricity is getting to the tip. And a warning light on front of unit turns on. Your help in diagnosing the problem is greatly appreciated

Check the contactor contacts for pitting. if severly pitted, replace contactor. If a death grip on the switch makes it work better then a light touch- replace the trigger switch.

Have you watched to see if the pressure light comes on right before shutdown? If so you may need to add a tank right next to the torch base to address the pressure drop assuming your air source is able to deliver adequate volume to the cutter continuously and you currently have more than 25 feet of hose between cutter and compressor. It might not hurt to check the internal filter as well.

You may need a better air supply. Also check the tip. This sometimes happens with mine when the tip gets pitted, not sure why but changing the tip sorts it out. They are fussy machines in some ways. Dont like dirty material, need a good earth.

Is the compressed air pressure in the limits for the unit to work. try turning the pressure up.

Check compressed air pressure is in limits otherwise unit will cut out. Try adjusting the pressure up. also make sure the supply pressure is correct as it may not be your plasma cutter at fault.

Possibly an internal short in the torch tip... the expendable components failing in the tip will cause the sensors in the machine to register a "no cut" or "free air arc" state and kill the power to the tip to prevent damage to the unit. Replace the tip components and double check the grounds connections.

Possible failure of the trigger switch and or the cable back to the unit. Use an ophmmeter to check that the trigger and cable are good,

Then with the ohmmeter check the continuityu of the cable to the electrodes,

Connectors are always suspect.

These are starting ponts to check.

Try using fine sand paper and clean the tip of electrode and the thing that looks like thimble, another solution was don't tighten tip cover too much back off a little til you ge good contact. some units don't like to be clicked ON without making contact with working metal, you may get two or three clicks and then nothing til the air stops flowing.

go to miller.com they have downloads for most everything they make. it sounds like you might have a ground problem or a bad connection in the tip

Ck the ground and the condition of the tip. The more it gets concave the harder it gets to get a arch. Gun angle is also important, hold at right angle to work and don't forget a very good ground.