As zzr1200 implied, the fault sounds like a problem with the power selector switch. The internal contacts can burn, break off, or the spring pressure can fail. The activating cams can slip on the shaft. However, the first place to check would be all the external screw terminals, especially for the links that join the switch segments in series. Obviously, do this with power off and the machine unplugged.
If you disconnect any wires from the switch, make sure they are labelled first. Don't be tempted to dismantle the switch - they self-destruct when opened!
Thank you for the help ive loaded pictures not shore if its rocker or rotaryAre the control switches, rocker or rotary type?
Pictures of the welder would help...
Ive loaded pictures thank youAs zzr1200 implied, the fault sounds like a problem with the power selector switch. The internal contacts can burn, break off, or the spring pressure can fail. The activating cams can slip on the shaft. However, the first place to check would be all the external screw terminals, especially for the links that join the switch segments in series. Obviously, do this with power off and the machine unplugged.
If you disconnect any wires from the switch, make sure they are labelled first. Don't be tempted to dismantle the switch - they self-destruct when opened!
Ive looked at the wires and plugs all look good, I’ve put a picture showing the voltage coming from the switch settingsThank you for the photos. There are two power selector switches: one rocker switch for "MIN" and "MAX", and one rotary for three ranges: 1,2,3. So there are 6 power settings in total, MIN 1,2,3 and MAX 1,2,3.
When the welder works correctly on setting "1", is this MIN 1 or MAX 1 ?
Does it fail on all of the remaining 5 switch combinations?
I would still suggest initially checking for a contact problem with the switches, as in my post #3. The rotary switch probably has screw terminals, the MIN/MAX rocker switch will have push-on spade tags and these can become loose.
If you put a DC voltmeter between the tip of the MIG torch ( +ve ) and the work return clamp ( -ve ) and press the torch trigger, you should see about 15 volts on the lowest power range, rising in steps to about 30 volts at the highest of the 6 settings.
Do you think it has had it’s day ?The voltage range is spot on.
Plus setting one uses the full primary winding, so the transformer is fine.
The rectifier is fine, as is the PCB.
There must be a high resistance connection somewhere.
I’m not sure what else to check wellington welding want £55 an hour to look at itNot at all, it looks in good condition.
As Hutcho mentioned, it is basically a re-branded Clarke, so there is no problem getting new or used spares.
Yes removed the bag from the rotary all connections are goodDid you remove the plastic bag type cover from the rotary switch to check the connections, as mentioned earlier?
One might be loose or corroded.
Works on min & max on 1 if I use 2&3 it won’t weld just makes a humming noise with a little puddle of weldAs mentioned, a high resistance somewhere will give correct voltages but low currents. You say it works on setting 1, is this both 1 MIN and 1 MAX then it's inadequate on 2 and 3 (both MIN and MAX)?
I had a corroded work return clamp connection that was hidden by the rubber boot and insulation, but if yours actually welds there shouldn't be bad joins. The connections to the rotary switch or to their windings in the transformer may well be poor.