- Thread starter JuniorMIG
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Hello sorry I havent had a chance to post in a while ive been revising for my gcse's that started today... but yea I want to see if there is a potential difference between my ground and torch, even though I have no wire feeding through. I have an inch of wire coming out of the torch, is it safe for me to attempt a spot weld in order to check if the welder still works?
the snooper
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you only need to put a multi meter across the earth and torch that will tell you if the transformer has power failing that try arcing the inch of wire
any suggestions why this is happening? could it be the motor?
rtbcomp
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The motor per-se won't prevent a spark happening. Going by the circuit diagram if the transformer/rectifiers are faulty neither the motor nor the arc will work.
You really need to check the diodes and transformer output when your dad's finished using his multimeter.
You really need to check the diodes and transformer output when your dad's finished using his multimeter.
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Sean
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from the photos id guess the motor feed relay is onething need to be looking at - on the PCB its the see through blue Lego brick with the scorch mark in it , you can test the motor by pulling off the wires and conecting it(motor) to 12v, car battery handy? but the motor feed runs of the welding current on these machines so if the weld current has failed the motor wont run. is it live you havn't popped another fuse?
the snooper
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you state the machine is no longer blowing the fuse, if the diodes have gone and there is power getting to the main welding transformer it should be buzzing very badly when you pull the trigger, chances are something else has added to the list now ie what ever was shorting out has now caused a failure elsewhere stopping the power reaching the original fault.
as above, unless you do some basic tests with a meter you are going to go round in circles guessing
BrokenBiker
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right. Lets start from the begining.
when you switch the machine on, does the light come on? Does the fan start up? If no then you have a mains power problem, likely to be the switch or a broken cable, or the fuse in the plug. If this all.works them move onto the main transformer. Check for 240v going in, and a much smaller voltage on the other side. If no voltage, tranny is dead. If you get voltage, check the rectifier. This can be done with the resistance setting on a meter. You should get high resistance one way and low resistance the other on each diode. The wire feed motor appears to be centre tapped off the welding tranny, test the voltage at the centre tap and ground, if you get voltage, look at the relay controlling the motor, this should do the switching for the motor and the main contactor for the rectified welding current. Then look at power switches and wire feed pot. These again can be tested using the resistance setting. Check the motor windings for resistance, it should be fairly low, if there is no reading it is dead. Check the thermal overload, this will cut the welding current, therefore stopping the feed motor too, just because the light isn't on doesn't mean its ok, the bulb could have blown.
now if by some miracle all of these things appear to be working ok, you have to start tracing wires and testing each one for breaks or damage.
if they are all ok then the fault will probably now lie within the pcb, in which case just get a new pcb, it save so much heartache when you replace a blown component to find you have destroyed another with the heat of the iron, its far easier to just replace the board
oh, the torch switch needs checking too. Both for continuity and voltage supply.
after looking back through the posts though and the pictures, it looks lime the contacts in the blue relay have blown, in sure the burn marks aren't part of the original design, that needs investigating even if the relay does work fine. Burn marks don't appear for no reason, especially on a 12v dc relay with little to no current flowing through it
when you switch the machine on, does the light come on? Does the fan start up? If no then you have a mains power problem, likely to be the switch or a broken cable, or the fuse in the plug. If this all.works them move onto the main transformer. Check for 240v going in, and a much smaller voltage on the other side. If no voltage, tranny is dead. If you get voltage, check the rectifier. This can be done with the resistance setting on a meter. You should get high resistance one way and low resistance the other on each diode. The wire feed motor appears to be centre tapped off the welding tranny, test the voltage at the centre tap and ground, if you get voltage, look at the relay controlling the motor, this should do the switching for the motor and the main contactor for the rectified welding current. Then look at power switches and wire feed pot. These again can be tested using the resistance setting. Check the motor windings for resistance, it should be fairly low, if there is no reading it is dead. Check the thermal overload, this will cut the welding current, therefore stopping the feed motor too, just because the light isn't on doesn't mean its ok, the bulb could have blown.
now if by some miracle all of these things appear to be working ok, you have to start tracing wires and testing each one for breaks or damage.
if they are all ok then the fault will probably now lie within the pcb, in which case just get a new pcb, it save so much heartache when you replace a blown component to find you have destroyed another with the heat of the iron, its far easier to just replace the board
oh, the torch switch needs checking too. Both for continuity and voltage supply.
after looking back through the posts though and the pictures, it looks lime the contacts in the blue relay have blown, in sure the burn marks aren't part of the original design, that needs investigating even if the relay does work fine. Burn marks don't appear for no reason, especially on a 12v dc relay with little to no current flowing through it
rtbcomp
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If a shorted diode has since burnt itself out to an open circuit the transformer shouldn't buzz.
the snooper
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very true, there are lots of possibilities without ant actual tests
Hi guys I am new to this forum group I have a problem with my mig welder SWP Proline 241 it's blowing the fuse 40 amps without wire or welding with it
any suggestion on this problem also anyone knows where I can find a wire diagram with the values of the compounds as the one, I have has no values at all
Thank you.
Brian
any suggestion on this problem also anyone knows where I can find a wire diagram with the values of the compounds as the one, I have has no values at all
Thank you.
Brian
skotl
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Hi Brian, welcome to the forum.
You're better off starting a new thread rather than resurrecting an eleven year old one, especially as this is in the SIP section and your welder is an SWP (which aren't the same despite two letters matching
)Just head over to https://www.mig-welding.co.uk/forum/forums/welders-and-welding-machines.15/ and create the new thread there as there isn't a dedicated SWP section.
skotl
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Actually, you already asked the same question here: https://www.mig-welding.co.uk/forum/threads/swp-mig-241-proline-welder.143288/ and got a couple of responses that you haven't replied to
