lincoln 185 compact mis-behaving

[beelzedub]

i'm having issues with my lincoln electric 185 compact.

the problem is when the machine is when i pull the trigger on i can hear the contactor pulling in and hear the gas coming through the solenoid, but no wire feed and no arc???????????

i have changed the pcb for a new one and it made no difference.

now on close inspection i have noticed a broken wire on the main transformer, so not sure if this will cause the issue or is un-related as i had a problem a few years back and the engineer who came to fix it said that something was wrong with the windings and he had to bridge the switch so that powers 4-5 were the same.

can anyone please advice me where to look or whether it is safe to reconnect said broken without it causing something else to blow.

thanks Mike.

 

[mike 109444]

Welcome Mike
If you have no wire feed then how do you know you don't have an arc?
Have you tried releasing the wire feed rollers and pulling through say 6" of wire, then re-clamp wire and try triggering onto the ground clamp to see if you do still have an arc. If not then realize that some welders take there power for the wire feed from the same voltage as the welding voltage. This may be fed onto the pcb as a DC voltage (24v?) at the X2 connector ?
Post a pic or two of the "broken wire" and pcb to try and help with diagnosis.
You could test/confirm the feed motor is working by connection to a 12Vdc supply/battery charger (remove both existing connections to motor to avoid feed 12 volts INTO the pcb!)

 

[beelzedub]

Thanks Mike for the Welcome and the quick reply.

i have tried the motor connected to a car battery and it spins freely, also pulled wire out and tried arcing off the return lead and nothing.
will try and take a pic in a bit.

thanks again Mike.

 

[beelzedub]

 

[mike 109444]

In the first pic WITH THE MACHINE UNPLUGED gently part the wires that are bunched together so you can get a better look at whats there. Note the sleeving may be a bit crispy! You need to see if there are two ends, the one you have already noticed and where it went to. It should not be far away. The end you have seen may have been left by the previous engineers work. Once you have it spread out a bit, see if you can get a better pic (set camera/phone on macro). Then for now leave it. Note this is the large red circle on the diagram.
With the machine plugged in and turned on, meter between the 2 pins on plug X2. This is where the red lines are on the diagram. Set meter to DC volts and you may need to get some help as you will need to hold probes on and pull trigger. You should see a DC voltage between 12 to 30 ish volts DC.
If there is no voltage then it could be the main transformer primary side (Big red circle) (one with the broken wire) or the secondary side of main transformer (Small red circle) or or the diode pack.
Might need some more pics to be able to point you as to where to check/test.
I have assumed you have or can get access to a meter.
I also assume that the diagram is of your machine!!
have also included unmarked diagram.

 

[normspanners]

is it an optical illusion or is that ALL a bit crispy looks like quite a bit of carbon on the tranny and tails.

 

[beelzedub]

not crispy, apart from a couple of bits that have chaffed its very supple. its covered in a sticky waxy film and dust has gathered hence the burnt look.

Mike, i can see both ends of the broken wire within the sleeving, there is actually 2 wires within that sleeving one of the two is the broken one.

i have tested across X2 and it was set on 20 and read 0.22 before pressing the trigger and whilest holding the trigger it climbed to 0.97

thanks again Mike

Mike.

 

[mike 109444]

The voltage at X2 is wrong indicating it is not getting it's voltage which comes from the diode pack and it's voltage come from the secondary of the main transformer and that voltage comes from the transfer of voltage across the transformer from the primary side !phew
The attached sketch (not a good one) shows two ways that it could be wired/wound on the main transformer. If you look at the sleeved wires that go from the transformer and up to the power selector switch (then back down the same sleeve) can you see if there is a loop formed at the end on the switch? that would indicate that it is wound as per the option 1. If you then had a break in the wires as indicated at the red X's you would loose some of your power selections BUT SOME may still work (have you checked ALL the power settings to see if wire feed works on any ?
I am trying to be careful as to suggesting you start poking around the mains that is in this machine as I don't know your level of knowledge/safety.

 

[normspanners]

I am trying to be careful as to suggesting you start poking around the mains that is in this machine as I don't know your level of knowledge/safety.

somebody else who uses an APP to illustrate on here!!

A Paper n Pencil

 

[mike 109444]

You might be able to repair as in pic Note you must scrape the enamel (the red coating on wire) off the ends before connecting.

 

[mike 109444]

Would be nice to down load an APP to my company phone to make it work as a Bl**DY PHONE !

 

[beelzedub]

i hope these pics might help show the switch wiring and the broken wire and where it goes on the trans.

 

[mike 109444]

It does look to be using the option 1 way of taking the taps from the transformer out to the switch and back again.
If the arrows on the pic attached are indicating the broken ends the you should be able to join it as per my post 10 assuming there is enough length on the broken bit coming from the transformer. Remember to scrape off the enamel.

 

[beelzedub]

yes Mike that is correct about the broken wire and yes a choc block would do it. does everything look correct at the switch end then?
i'm guessing that the repair that the guy did a few years ago is the 2 black bridge wires as seen at the switch?

 

[mike 109444]

When I looked at the switch I did think the black link wire looked "added" so that would tie up with it having been bridged for one power setting to another to avoid a blank power setting. Could be there is a break in the older faulty wire much like the fault you currently have. The break could be inside the sleeving?
In your post 12 2nd pic on the left where the black link wire goes is that only one of the enamel wires going to/from the switch screw terminal? and is there a second one folded back into the tiewrap/heatshrink tube?

 

[beelzedub]

yes Mike, where the black bridge wire goes to the switch terminal the wires to the trans have only one attached and the other is folded back and tie wrapped into place.

 

[mike 109444]

You would be best leaving the previous repair alone!
The switch wires look ok as far as I can tell.
If you join the wire as per post 10 try to keep the choc block clear of the other cables, if necessary move them to one side. Reason if the choc block gets hot the outer may start to melt! Try to make sure the screws are nice and tight on the choc block as a poor connection here will result in a resistance which will cause heat. Once you have joined try a short weld to confirm working then run an inch or two of weld and then unplug and check heat around the connection. Note it will get hot in use. Extra fan needed ? Is the original fan working properly, vent clear ?

 

[beelzedub]

didn't work :-(

 

[mike 109444]

Think you now will need to check there is an output FROM the contactor TO the power switch. If the contactor is labeled, then you need to find the connections 2 and 4 (they should have a capacitor across them). Now with the power on, meter between the two connections on contactor 2 and 4 (looking for 240vAC when trigger is pulled and contactor operates). If ok then with the power OFF / machine unplugged, follow the wires to the power selector switch and note which they go to. They should not be any of the sleeved wires as they go to the transformer. May be the black pvc covered wires ? These wires are the supply TO the switch, which then via the switches position, selects which part of the transformer is selected! You can meter (with it set to ohms) between one of these wires and where it connects on the contactor and then same with other wire. This will confirm that the output from the contactor should be going to the switch (safer than trying to meter these connections on the switch with mains present!!). If that's ok then find the two thick wires that come out of the transformer and go to the diode pack/rectifier Now meter (set meter back to VOLTAGE AC) this pair of wires with meter set on AC and look for about 15 to 40 vAC when pulling trigger. IF ok then you have a fault with the diode pack/rectifier. If not ok then fault must be with switch OR transformer.
Let me know the outcome so can advise further.

 

[beelzedub]

hi Mike thanks for all your help so far and sorry for such a long time since we spoke.

from the above post i have checked across the rectifier and have nothing. i have checked the 2 sleeved wires on the contactor that are labeled 2 and 4 and have 240v when trigger is pulled although i cant see the capacitor that you mentioned. now its the next part that is confusing me.

If ok then with the power OFF / machine unplugged, follow the wires to the power selector switch and note which they go to. They should not be any of the sleeved wires as they go to the transformer. May be the black pvc covered wires ? These wires are the supply TO the switch, which then via the switches position, selects which part of the transformer is selected! You can meter (with it set to ohms) between one of these wires and where it connects on the contactor and then same with other wire. This will confirm that the output from the contactor should be going to the switch (safer than trying to meter these connections on the switch with mains present!!).

do you have a contact number that i can call you on so you can talk me through it.

thanks again Mike.