Hi all
I've been lurking on this forum for a few years, but only just got around to registering to post a question. I have learnt a huge amount of information from following discussions here, so I'm very grateful to the many great people here.
I have just replaced my cheap nasty hobby MIG welder (approx 90A) with a Tradesmig 165 which arrived with a couple of faults. The transistors and a couple of capacitors and resistors needed replacing on the main circuit board, the bleed resistor was missing (15R 25W for a couple of quid from CPC seems to do the trick) and the wire feed motor gearbox needed putting back together. I am sure that the contactor is in pretty rough shape too, the bleed resistor contacts only work sometimes and the machine seems to be intermittently low on power. I read a thread on here from someone who had soaked the contactor in contact cleaner and then it worked better, but I started thinking that a contactor is just a big relay, so why not replace the 25A contactor with a 25A or 40A SSR (I have a spare 40A SSR http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=181443312530 which cost £2.78 including postage).
I would still need to add a relay for the bleed resistor (normally closed, open when welding), but I have a box full of 30A 12v change-over relays that should do the job. Does anyone think this is a stupid idea, or could the SSR remove all the problems with using a mechanical relay to switch a heavy inductive load in a dirty environment?
Thanks in advance,
Mike
I've been lurking on this forum for a few years, but only just got around to registering to post a question. I have learnt a huge amount of information from following discussions here, so I'm very grateful to the many great people here.
I have just replaced my cheap nasty hobby MIG welder (approx 90A) with a Tradesmig 165 which arrived with a couple of faults. The transistors and a couple of capacitors and resistors needed replacing on the main circuit board, the bleed resistor was missing (15R 25W for a couple of quid from CPC seems to do the trick) and the wire feed motor gearbox needed putting back together. I am sure that the contactor is in pretty rough shape too, the bleed resistor contacts only work sometimes and the machine seems to be intermittently low on power. I read a thread on here from someone who had soaked the contactor in contact cleaner and then it worked better, but I started thinking that a contactor is just a big relay, so why not replace the 25A contactor with a 25A or 40A SSR (I have a spare 40A SSR http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=181443312530 which cost £2.78 including postage).
I would still need to add a relay for the bleed resistor (normally closed, open when welding), but I have a box full of 30A 12v change-over relays that should do the job. Does anyone think this is a stupid idea, or could the SSR remove all the problems with using a mechanical relay to switch a heavy inductive load in a dirty environment?
Thanks in advance,
Mike
