EWM MIG welder stopped functioning after wire run out

[charlidson]

Hello MIG welders,
My quite old EWM MIG welder (Phoenix 335 Progress puls TKM) posted the message 'PHO 371' on its display exactly as the welder spooled out of wire mid welding some 3mm box section. I contacted EWM and they said to press the wire feed motor reset (Doh! Obviously) and if this didn't work then "it is a sign of a not functioning bus communication between our control boards".
I have subsequently contacted a local EWM approved service centre and they said it wasn't spending any money on this machine as spares where difficult to obtain.
If anyone has any idea why this fault happen and what might have failed I would be happy to hear from you.

Charlidson

 

[500e]

how old so we know what to buy

 

[hotponyshoes]

First thing to try is a hard reset by removing the power (turn it all off and on again)

Reasons why it happened?

1, Coincidence. Apart from physical damage (dropping, impact, corrosion) , there are only 3 times an electric circuit can fail. When it starts up, when it's running and when it stops.
So, you had a one-in-three chance of it failing when the wire ran out. Ie, it would have failed then if you had released the trigger anyway.

2, Issue with the reset button. If the very end of the wire was attached to the drum and the feed rollers were tight enough the motor would see an overload. If the welder has a mechanic breaker that will trip out. That breaker may well have 2 sets of contacts. One to remove power from the motor and another to tell the welder that the trip has activated causing it to show an error code. As it won't get used very often its possible those contacts have got dirty or corroded and are not making circuit even if the breaker is resetting correctly.

Unfortunately I don't recall seeing a physical reset for the feed motor on an ewm. If yours has one start by checking it. I think they just have a motor drive board that presumably has some sort of current sensing ability. Again, as above, odds of it failing at that point are high because that's the only time it gets activated. I've no idea how it's wired up. Potentially, if that board is just broadcasting an error status you could unplug that board and see if the error goes away. I suspect you'll just get a new 'no coms' error though.

3, the end of the wire was not fixed to the end of the drum.
When you reached the end it has sprung off the drum and made contact with the case. The wire is live and has shorted something out.
This is fairly common when you get a big birds nest and keep pulling the trigger.
I've seen it quite a few times on cheap hobby machines and (apart from some paint damage) it's not caused a problem.
I'd like to think a machine like an ewm would have some sort of protection for this but they do have a lot of sensitive electronics inside compared to the cheap machines..