Andy - Electronic Engineer here - you can probe the track with the potentiometer apart using your multi-meter to probe from black (or red) and touch various parts of the track on its circumference (90deg, 180degm, 270deg), and take measurements. You should be able to work out the actual value by estimating your far along the track you get a reading [given your black-to-red open circuit, the track is broken somewhere, but it probably wont be everywhere]. One last point - as you sure absolutely sure the original potentiometer was not a logarithmic type? If the orig is a 10k log then you could get the behaviour you see if you fitted a 10k linear. Cheers from over the ditch.
Hi Andy, If you pick off the black disc on the original knob you will see a nut to adjust a collet into the pot shaft. worked on these machines for many years.
Did the old potentiometer have any numbers on it? You may be able to deduce the value from them. For instance 10k would be 103 (10+3 zeros), 1k is 102 (10+2 zeros) and 2k is 202 (20+2 zeros). Just stumbled on your channel - lots of interesting content.
Ah, interesting as I wouldn't have recognized that. I'll take a look when I get a chance. Old part now in the bin but may be on the footage. Thank you & welcome to the channel Andy
My very first mig welder was a three phase murex 180, the best welder I ever owned, got that in 81. I purchased a Migatronic in the early 90's as I needed to be able to weld at 300 amps continuous on a job I had at the time and for some reason gave the murex to my brother in law who ran it for several more years then threw it into a skip when one of the diodes blew out. I told him the diodes were replaceable but by that time the skip had been collected from his works, I still have the manual and circuit diagram from that Murex some where in my collection. There should be continuity between the two outer pins on the pot. but it wont show on the continuity setting on the meter as it will be the ten K of that particular pot. Prise the black cap off the red knob and there is a nut that clamps the knob to the shaft, the shaft is not supposed to come away like it did. I always blow the dust out of my welders once a year, do the computers as well.
That was interesting to see some of the switches protected on the back with plastic. Good idea. As you mentioned, no manufacturer would do that now. Don't know if it would help too much on potentiometers however. My experience is pots usually are the first components to fail, even in relatively clean environments like power generator switchboards. Also, your EV burning battery observation safety lens for your camera makes recording/viewing of MIG welding, very high quality. Good video Andy.
Thanks Connor, yes, I do like my little camera safety shield, seems to work pretty well & like you say, could be useful for other similar applications - I'll ensure it's to hand the next time an EV drives past! Take care my friend. Andy
Andy - Electronic Engineer here - you can probe the track with the potentiometer apart using your multi-meter to probe from black (or red) and touch various parts of the track on its circumference (90deg, 180degm, 270deg), and take measurements. You should be able to work out the actual value by estimating your far along the track you get a reading [given your black-to-red open circuit, the track is broken somewhere, but it probably wont be everywhere]. One last point - as you sure absolutely sure the original potentiometer was not a logarithmic type? If the orig is a 10k log then you could get the behaviour you see if you fitted a 10k linear. Cheers from over the ditch.
Hi Andy, If you pick off the black disc on the original knob you will see a nut to adjust a collet into the pot shaft. worked on these machines for many years.
a decade box resistor will be a good investment mr young . a excuse to buy more tools
Did the old potentiometer have any numbers on it? You may be able to deduce the value from them.
For instance 10k would be 103 (10+3 zeros), 1k is 102 (10+2 zeros) and 2k is 202 (20+2 zeros).
Just stumbled on your channel - lots of interesting content.
Ah, interesting as I wouldn't have recognized that. I'll take a look when I get a chance. Old part now in the bin but may be on the footage.
Thank you & welcome to the channel
Andy
Awesome 👍
My very first mig welder was a three phase murex 180, the best welder I ever owned, got that in 81. I purchased a Migatronic in the early 90's as I needed to be able to weld at 300 amps continuous on a job I had at the time and for some reason gave the murex to my brother in law who ran it for several more years then threw it into a skip when one of the diodes blew out. I told him the diodes were replaceable but by that time the skip had been collected from his works, I still have the manual and circuit diagram from that Murex some where in my collection. There should be continuity between the two outer pins on the pot. but it wont show on the continuity setting on the meter as it will be the ten K of that particular pot. Prise the black cap off the red knob and there is a nut that clamps the knob to the shaft, the shaft is not supposed to come away like it did. I always blow the dust out of my welders once a year, do the computers as well.
That was interesting to see some of the switches protected on the back with plastic. Good idea. As you mentioned, no manufacturer would do that now. Don't know if it would help too much on potentiometers however. My experience is pots usually are the first components to fail, even in relatively clean environments like power generator switchboards. Also, your EV burning battery observation safety lens for your camera makes recording/viewing of MIG welding, very high quality. Good video Andy.
Thanks Connor, yes, I do like my little camera safety shield, seems to work pretty well & like you say, could be useful for other similar applications - I'll ensure it's to hand the next time an EV drives past!
Take care my friend. Andy
Lots of arc dust on the contractor. Are you going to blast the lint & dust out of the interior of the cabinet?
Yes, most definitely, amazing how it has built up over the years 😀
@@AndyMechanic
Nice tune up.
Hey Andy are you using argonsheild or CO2 just curious cheers , shaneo, Nelson, 🍺👍
Argoshield Universal, always have. Get it from BOC
Yes I have that as well andy