Help me understand my plasma cutter

I have a SnapOn YA2001 plasma cutter which I believe is a Century 2040. I
bought it broken but I got it working for one day, then it stopped working
again. When I first got it had a hard time establishing the arc. After
it worked for one day it now has a hard time starting the arc again.
Can you help me with a couple of questions?
There are two leads going into the torch. One with a air hose and one
with a braided wire in it labeled pilot:
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When I blow air through the air hose lead it comes through the torch fine.
When I blow air through the HF lead no air comes out through the torch is
this right?
Inside the cabinet the compressed air goes to a solenoid and then Y's off
to the torch lead and to the HF lead. Without any hoses attached, full
airflow comes out of the torch lead but only a minimal amount through the
HF lead. This confuses me as well because I see nothing that would cutoff
the air pressure to the HF lead:
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Is this what should be happening?
The HF circuit sparks only for about 5 seconds when I press the torch
switch. Is this right? Should it be on continously?
I would appreciate any help you can give me. Thanks.
Aloha, Russell
Reply to
Russell Shigeoka
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Russell, I wanted to try to help but your web page will not load. Michelle
Russell Shigeoka wrote:
Reply to
Michelle P
Worked for me and fast loads. Perhaps it was the time of day.
I'm not a plasma type myself - but the pictures have good documentation. Martin
Michelle P wrote:
Reply to
Martin H. Eastburn
I would say this would be correct, Air must be expelled from the torch for the pilot arc to strike.
I am a little unsure that you have two air supplies. It is normally only one. The supply to this may be a safety device to shut off the machine if you remove the cap. The main air flows through the torch lead to the head (electrode ) of the torch and the air flows around the electrode and is expelled out of the nozzle.
No this appears correct.
I suggest the following
1) Remove one of the leads from the machine end of the torch, also remove the electrode and nozzle from the gun. 2) Meter the resistance accross the torch leads this should be open circuit (not shorted) 3) Replace the electrode and other consumables on the torch, then repeat the test at the machine end again the circuit should be open. 4) Check the conduction of the two leads, place the meter between the torch connection and the electrode of the torch the inner part and check for continuity 5) Repeat this test with the pilot lead.
IF all appears well the torch is good and should be refitted to the machine.
If this is OK turn on the machine with the torch fully fitted and look at the end of the torch from the side DO NOT LOOK DIRECTLY INTO THE TORCH END!!! this may be better to darken the room so that you can see the HF spark. Press the start button and see if you hear a fizzing noise and a small spark across inside the torch head. If this is so then you appear to have a pilot arc circuit problem.
I would need to know what machine you have to assist further.
Hope this helps you
Kind Regards
John Herbert Service Engineer Welding Equipment U.K
Reply to
John Herbert
test please ignore
Reply to
John Herbert
Ok - have you put the hose (since it is in a hose protector) in a tray of water - get bubbles ? Did the prior owner rub a hole or almost did and pressure blew it out - now a leak in the sleeve ?
I suppose you could get a spare end plug (not torch end) and plug it in and see if air comes out of it. Then see if you can pressurize the hose some way. Martin
Mart> Worked for me and fast loads.
Reply to
Martin H. Eastburn

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