Clarke 110en Turbo MIG welder - problem

[biker1981]

Hi I have just bought a clarke110en Gas/no gas welder... it was second hand but never been used. I ve been using it perfectly fine.... untill it stopped feeding the wire.

I took the case off and all the wire was tangled, i un tangled it but still not working the fan spin and it clicks when i press the button... but the Motor doesnt turn.

I have checked the power and there is no power to the motor... so I guess its the PCB.

Can anyone advise me how to check this for sure as it all looks fine. also where can you buy parts from i.e the PCB.

any help appreciated.

 

[mike 109444]

Not sure what you are like with a circuit diagram but follow this link and download the manual http://www.mig-welding.co.uk/forum/showthread.php?t=15737
Unfortunately they don't give much of the pcb circuit. The feed motor is on right side of diagram.
This pic is of another members 130EN pcb. Nit sure if yours is same?
There is a fuse on the right of pcb (5amp) can't see that being cause but worth a check. The transistor in top left (BT 151) is the device that the wire speed control acts on to vary the voltage going to the motor. Could be blown (not that expensive, ebay search?)

 

[biker1981]

thaks for the help,

mine is a little different... it doesnt seem to have a fuse on the board.

Also im not that good at electics so prob couldnt take the board appart. where would I get a pcb from to repalce it ?

 

[biker1981]

I have this printer board.... which doesnt have fuse

 

[mike 109444]

thaks for the help,

mine is a little different... it doesnt seem to have a fuse on the board.

Also im not that good at electics so prob couldnt take the board appart. where would I get a pcb from to repalce it ?

Think you have answered your own question. The pic you posted is from Weldequip. The price is on his web site as well (see link at top of forum page)

If you want to have a go at fixing it then suspect the transistor device as in pic. The board does have a fuse but it's just a bit of fuse wire!! (really trimming the cost down there)

 

[biker1981]

if its a stroing chance its the realy i fancy having ago at replacing it. never soldered on a circuit board... but would give it ago

 

[biker1981]

How do I know what part to buy please?

 

[mike 109444]

If when you press the trigger you hear a click, that should be the relay on the pcb which should mean it's ok. The transistor device is the likely cause. There should be a number printed on the front of it
This is NOT the part but it will look like this. http://www.ebay.co.uk/itm/Transisto...al_Components_Supplies_ET&hash=item2ec7c0f252
You need the numbers from it then you can do a search on ebay and you might find it's less than £5 delivered. You might want to search out a friend or relative that has don some pcb soldering as it's not easy to explain on the net! Would only take some one that has done that type of work 5 mins to replace the component (usually takes longer for the soldering iron to heat up!!)

 

[biker1981]

Thanks alot for your help ... really appreciated


Ive taken the PCB out and can see the transistor but I can t read the serial number so will remove first.

With reagrds to the solder.... is it special type? or just normal solder?

 

[grandads_shed]

just check that the back of the motor ie pushed on properly, i had this poblem with mine a few weeks after buying it, it was just this, i pushed it on fully and never had a problem since

 

[mike 109444]

Depends on what you mean by "normal solder" The solder for electronic soldering will have a flux core (a paste that runs down the middle of the solder). Obtain from maplins

 

[mike 109444]

Basic de soldering:
Before you plug your soldring iron on if the tip is mucky then run a file over it to get it to a copper colour.
Then once you have pluged it in an allowed it to heat up, dab a bit of your solder on the tip of the soldering iron. This will give it a coating of solder known as "tinning" the iron.
Now get some tv coax and strip the outer coating from about 6 inches. This will revil the copper braid/screen. Push this back to revel the inner insulator and core. cut the inner away leaving just the outer braid. Flatten this. This will now work as a wick (sponge) to soak up the solder around the pins of the transistor.
Now turn the pcb so you are looking at where the pins of the transistor poke through the board. If you now put the end of the braid over one of the pins and hold the solder iron on it, after aprox 1 min the solder from that pin should soak uo into the braid. Repeat for the other two pins and now you should have removed most of the solder holding the transistor onto the pcb. With a genital rocking motion and maybe a dab from the iron it should be possible to remove the device.
Now you can meter it or replace.

 

[Robotstar5]

Now turn the pcb so you are looking at where the pins of the transistor poke through the board. If you now put the end of the braid over one of the pins and hold the solder iron on it, after aprox 1 min the solder from that pin should soak uo into the braid. Repeat for the other two pins and now you should have removed most of the solder holding the transistor onto the pcb. With a genital rocking motion and maybe a dab from the iron it should be possible to remove the device.
Now you can meter it or replace.

I suspect the transistor will need replacing with that much heat applied?

I prefer to use a desoldering pump quicker and less heat input

 

[biker1981]

Thanks for the help.

so i bought a soldering iron, I bought a desoldering pump, I bought soldering wick stuff. and the transistor.

Put the new one on and just put a small dab of solder on each prong.... plugged it all back in and....... NOTHING.

hmmm... so what could i have done wrong, i have kept heat away from the new resistor, kept the soldering clean and not crossing over. could it be anything else ?>

 

[mike 109444]

When you said in first post that when the trigger is pressed you can hear a "click" if you still have the pcb fitted then press trigger and look at pcb to see if the relay is operating. You should see the relay flick over when trigger pressed then flick back when released. The relay in pic is similar to the ones fitted in some welders. So you can see what's inside. You may see a spark across the contacts, this is not unusual!
If the relay is working then it could be the smaller transistor (the black "D" shaped device) that maybe duff. It could also be any of the other devices on the board, so would need to go over it with a meter.

 

[biker1981]

Hi,

the relay is working fine clicks and I can see it moving. I have just replaced the back transistor

 

[mike 109444]

When you say "just" do you mean only the big transistor ? There is a smaller transistor on the board marked 2nd in the pic. Also there is if I recall a zenner diode on the board and I think it is just to the right of the small transistor but I don't recall the value.
I know that the transformer on the board can pack up but I think the voltage for the relay comes from that so should be ok.
You would need to have power to the board to check the transformer for 240 in and 24 v out so might be a bit dangerous.

 

[biker1981]

yeah I only did the big one, should i do the little one to now ? how do I know what part it is pleasE?

 

[mike 109444]

Marked on the front flat face should be a part number such as BC108 or similar. You may have to catch it in the correct light to read number.
There are various approaches to testing the board and the components but a lot depends on you ability to meter the board and some of the metering would be done with power (240V AC) being feed to the board so could be dangerous.
Can you post a clear pic of the underside and top side of the pcb. That would help to guide you.

 

[biker1981]

Hi,

Here you go.....

Does this look like the part i need. The numbers for the transistor look like KSP42 JD4... but this just says KSP42

http://www.ebay.co.uk/itm/KSP42-X2o...Supplies_ET&hash=item3a7f2192ab#ht_948wt_1012