sip topmig 150

[cruncher1959]

hi i used the welder th other day and the motor burnt out it was a 6-15v dc motor i brought two replacement motors and put one on that started burning right away so i checked the voltage at motor feed and it was ranging from approx 26v to 40+ volts with changing settings dose anyone have any idea why this is happening
thanks very much for your time and trouble

 

[shenion]

Sounds like it is the control board. Most likely the driver transistor is shorted.

 

[cruncher1959]

motor

here is a pic of the motor is it the correct one for the topmig 150

 

[mike 109444]

Recon the original (?) one (6-15 v) may have been wrong When you metered and got the 26 to 40 was the replacement motor still attached, if not then as there was no load the voltage may well rise, as 40 v does sound very high! Not sure what voltage motor is fitted to that SIP but would expect 12 or 24v motor.

 

[cruncher1959]

motor

hi i measured the voltage with motor off but when i replaced the motor with one of the new ones it sparked like hell and started burning out

 

[mike 109444]

Where are you getting these motors?
How sure are you that the 1st (original ?) motor was the "factory fitted one" Did you have the machine from new? A 6 to 15 v motor would work on a 12v system but on a 24v system and higher wire feed rate it would cook.
How was the original motor attached to the gearbox?
What gear did the motor have fitted?
I would have thought that if the driver transistor was shorted it would not adjust the voltage from 26 to 40v

 

[cruncher1959]

motor

hi the welder was a second hand one and that was the motor in there so i got two replacement ones from mfa so dont know if it was correct would anyone know the answer to that its a tough one

 

[mike 109444]

mfa ?

 

[cruncher1959]

sorry it was fixed by two screws down through bottom of gearboxand had a small brass cog hope that helps many thanks

 

[the repair man]

The standard motors are 24vdc definitely, buy a complete wire feed assembly off a clarke or similar and make it fit. It will weld a LOT better.

 

[cruncher1959]

hi repair man could you give me an idea of what to get regards

 

[cruncher1959]

here is picture of the top

 

[the repair man]

From that pic it looks like the link I sent would be an easy fit.
I would check tho' that one in link may be 12v, you need 24v or a 24v transfomer as well.

 

[cruncher1959]

ok many thanks

 

[mike 109444]

Reason I was asking about the way the motor attached is that I have a bucked load of these 24v DC motors. For the cost of the postage your welcome to try one. Have been looking for someone with a SIP motor problem to try one out.

 

[cruncher1959]

certainly looks like it may work or easily adapted for the job

 

[skotl]

I'm about to pull my motor out and grease the gearbox (as a preventative maintenance job), Mike. I also need to replace the PCB-mounted var-resistor so it would be a good opportunity to try an alternate motor and see how the speed performs.

Will drop you a PM

 

[mike 109444]

Reply sent

 

[cruncher1959]

sent pms

 

[mike 109444]

Could do with an update on these motors chaps.
Also need to know what work was needed to get them to fit (pics ?) Will have about 40 of these soon so need to sort.
Think Mr C1959 did say he had to drill some new holes. Did the original gear remove and fit to new easily? Do you think the original gearbox that is fitted to these motors would have fitted if the output shaft was the correct size. Is the final output shaft fitted to the machine a round or D'ed or squared shaft ??
Thanks guys.