Eland mig 130 with issues

[GraemeVW]

Things are getting SUPER weird!!

I cleaned the relay contacts and refuted the board.

The motor runs (It may have been before as it's now very quiet)

But, the motor runs slowly, the wire feed adjustment is reversed, and it has no torque at all, can stop the feed roller by touching it.

 

[GraemeVW]

Woohoo, removed and retested the small transistors and one is bad!

Fingers crossed that will sort it.

 

[GraemeVW]

It only works!!!!

Local shop had the 2219 transistors. Been there 3 times in the last couple of days, so handy having somewhere local!
They had a 556 timer too so bought one just in case as it was the only thing left. Doesn't seem to need it though.

So, bdx18 transistor broke, replaced that and all the diodes and caps. Then relays failed, taking out the 2219 drive transistors.

In future, it's probably easier to just replace all transistors, diodes, relays and electrolytic caps in one go!

Not checked how it welds, but all does what it should and wire feed seems quieter too which can only mean it's better

I'll lay some welds with it later and post them up for everyone to laugh at (I'm not that good).

 

[GraemeVW]

Just tried it and the original issue is still there.
Tried to video the weld, holding my phone inside my mask. Very awkward! I paid no attention to what I was doing. I can't stop what it's doing with any adjustment.
It welds fine for 1" then starts to stutter.

Don't know how I can post a video though.

 

[GraemeVW]

Does this work?

 

[GraemeVW]

Seems to always do the same thing, at the same time. Stop and start again and it repeats.

 

[GraemeVW]

I think this may be a roller issue. I run the roller while holding a triangular needle file in the wire groove to clean it out. It didn't feel nice and even. Tried it again after and it's better. Maybe not completely solved, but changed, in the right direction.
The roller isn't worn or damaged, but I think dirt and maybe a little corrosion is altering the pressure on the wire feed.

Might be barking up the wrong tree, but I'll play with it, see if it helps.

 

[GraemeVW]

Been playing with the feed roller and the spool holder and it seems alot happier.
The bad sounding bit in the middle was me just going over old welds and rubbish. This is just a bit of old steel I've been covering in weld while trying to test this welder.

Broke out the new parweld mask too, true colour is a revelation!

 

[hermetic]

put a new liner in it!

 

[GraemeVW]

put a new liner in it!

I did, new parweld steel one.

Edit, has new wire, new liner, new tip, new shroud, fresh full gas, and now all new pcb components.
Roller is perfect, motor is like new inside, not much else I can do!

 

[hermetic]

OK not that then, can you get someone else to run a bead whilst you look inside the welder for telltales? Does it have a bank of big capacitors for smoothing on the welding side, could be one of them?

 

[GraemeVW]

OK not that then, can you get someone else to run a bead whilst you look inside the welder for telltales? Does it have a bank of big capacitors for smoothing on the welding side, could be one of them?

I probably can, yes. I'll see when they are free.
It does have a big bank of caps, yes. I'll check them over.

Does the second vid suggest to you it still has issues then?

It seems reasonably ok, but I'm used to a tired, temperamental, old clarke so even of its not right this eland is still loads better!

 

[GraemeVW]

It would make sense if it still had an issue as it was doing what the previous owner said it did. And it was a fault that started. So something broke and I'm not convinced I've found it yet.
I may just have managed to get it to a stage where it works ok despite the fault.
It does seem a little finicky to get set correctly.

 

[eddie49]

Found these images in an old post

It is useful to have the correct circuit diagram in this thread. The symbol used for a transistor in that diagram is really old, a British-only symbol used about 1962 !
The diagram may be from this earlier Eland thread:

Eland 160 just died!

Hi All Just started up my Eland 160 for a bit of garage practice before tackling some welding on my Landy chassis. All was going fine for about 10 -15 minutes and then it suddenly died (fan went off and no wire feed). Initially, I thought my breaker in the garage had tripped, but I'm still...

www.mig-welding.co.uk

which has some useful info about the circuits on the PCB.

Chip seems to be a timer, so I guess that deals with the pulse and spot functions. No idea if it's off the shelf, or programmed though.

The UA556PC chip is a general-purpose CMOS dual-timer chip, like two NE555 timers. It is not programmed, the frequency is determined by the external components - resistors/capacitors/potentiometers. One timer is used for Spot and Stitch welding, the other generates the variable-width pulses for the PWM motor speed controller.

So, bdx18 transistor broke, replaced that and all the diodes and caps. Then relays failed, taking out the 2219 drive transistors.

The BDX18 and the 2N2219 transistors are coupled together, so excessive current in one ( e.g. due to shorted relay contacts ) would damage the other. I was going to say that they are wired as a Darlington Pair ( a high-gain switch ), but actually one of them is PNP and the other is NPN, so in fact they are a "Sziklai Pair". Learnt something new!

 

[GraemeVW]

It is useful to have the correct circuit diagram in this thread. The symbol used for a transistor in that diagram is really old, a British-only symbol used about 1962.
The diagram may be from this earlier Eland thread:

Eland 160 just died!

Hi All Just started up my Eland 160 for a bit of garage practice before tackling some welding on my Landy chassis. All was going fine for about 10 -15 minutes and then it suddenly died (fan went off and no wire feed). Initially, I thought my breaker in the garage had tripped, but I'm still...

www.mig-welding.co.uk

which has some useful info about the circuits on the PCB.

The UA556PC chip is a general-purpose CMOS dual-timer chip, like two NE555 timers. It is not programmed, the frequency is determined by the external components - resistors/capacitors/potentiometers. One timer is used for Spot and Stitch welding, the other generates the variable-width pulses for the PWM motor speed controller.

The BDX18 and the 2N2219 transistors are coupled together, so excessive current in one ( e.g. due to shorted relay contacts ) would damage the other. I was going to say that they are wired as a Darlington Pair ( a high-gain switch ), but actually one of them is PNP and the other is NPN, so in fact they are a "Sziklai Pair". Learnt something new!

I'll check that post, although it seems to be behaving itself at the moment.

The info on the timer is just what the guy in the shop today told me too. He sold me a lm556cn which he said is a different make so different code. He said it may be slightly different but probably wouldn't matter. It was 63p so I figured I'd buy it anyway. Don't seem to need it though. Wire feed seems pretty stable now.

As for the transistors, that explains it better for me. I had sort of twigged the relay failure might have killed one, which is why I took them out again. The bdx18 seems to have survived.

It is welding ok again now but is a little fussy about set up. It seems to have a wide window of settings that will weld stuff but a narrow margins where everything has to be right before it will weld nicely.
This might just me my inexperienced with decent welders though.

My old Clarke would just blow holes, or not penetrate, and when you got it between those, that's where you welded. No real ability to finely adjust.

I've not really tried to do anything proper with the eland though, just laid about 3' worth of random short beads purely just trying to work out what was playing up.
The final 4" of welding today went quite well, id happily use it as it sits right now to but weld 1mm steel.
No idea if it will weld nicely for more than 4" though, may loose stability, so early days on calling it fixed.

The mention of the cap bank is interesting. Made me wonder how stable the power is under load. They seem expensive to replace on the off chance though and I can't test caps that big on my multimeter.

I'll probably just use it for a while now and see how it goes.

 

[GraemeVW]

@eddie49
Some interesting talk in that thread about the contactor.

I've read a bit on here about blown transformers in these and I'm glad I at least don't seem to be suffering that!

If I am still suffering inconsitancies I guess the only possibilities are the bank of 6 10000u caps, some less than ideal connections somewhere, or the contactor.
I didn't really realise what the contactor does but if it's switching voltage into the welding transformer I guess the contacts are important, and subject to wear/tarnishing etc.

Now I at least have it working, and doing passable welds, and now I understand a little more about what everything does, I might take the whole thing apart. Then clean it properly and check all connections are good as it goes back together.

I may well have solved all it's issues though.
Seems alot more sensitive to roller pressure than my old clarke. The roller doesn't seem to grip as well even though it looks perfect, and any tiny inconsistency in speed, or roller pressure, seem to show up in the weld more than the clarke.

The clarke just spat wire at stuff. It's feed was FAR more inconsitant than the elands, but it seemed to matter less.

 

[a111r]

Did you test the rectifier, as per post #21, just to rule it out?

 

[GraemeVW]

Did you test the rectifier, as per post #21, just to rule it out?

Yes, measures fine. I 're tested everything on the board again today when I found the broken drive transistor in case the relay had took anything else out.

 

[GraemeVW]

Did you test the rectifier, as per post #21, just to rule it out?

Just 're read post 21, I didn't try heating them though.
When I was still at that stage I just replaced all the diodes, but I hadn't even noticed the bridge rectifier. I thought the set of 4 diodes was doing that job. Thinking about it, they are too small to be doing the main rectifying.
Maybe I should warm the rectifier up and 're test it.

I'm pretty sure I have one in my boxes of stuff from building amplifiers too.

 

[eddie49]

Did you test the rectifier, as per post #21, just to rule it out?

I think a111r is referring to the main, 4-stud-diode rectifier ( not the small one on the PCB ).