Gas solenoid issues (wiring)

admin

Hi guys.I just purchased a used Home depot 5000HD basicly a SP 175.  It was only set up as a flux core welder when I picked it up and saw it worked and it worked fine.  I purchased the gas conversion kit for the welder and installed it as per the insturctions properly, turned the machine on and the gas solenoid is not activating.Attached below is a wirng diagram for the circuit (link) and I find it to be very vag on what is actually going on.  I have powered the solenoid and know that the solenoid does in fact function, but both sides of the solenoid have 125v on both sides no matter if the trigger is pressed.At terminal H2 low I have 125v and at the H3 connector I have 125v (no switched ground I would assume)  I know nothing about these welders but using common sense I am assuming that I may have a control panel problem, or hopefully a small other problem.Any help in the right direction would be greatly appreciated?Page 30 has the diagram : http://content.lincolnelectric.com/p...r/im/IM791.pdfThanks Brandon!
Reply:Any one?
Reply:It sounds like you are measuring voltage from H2 to ground and H3 to ground. If that is the case then you will have 125v on each terminal. You need to measure from H2 directly to H3. You should measure 208v here when trigger is depressed as this is the same circuit that powers the primary of the weld transformer. Be careful of high voltages here.Gary Haunemail  [email protected]  http://haunsystemsrepair.com
Reply:Thanks Gary I will try that becaust I was measuring them to ground.  I know the solenoid works to ground so if it has 125v on both sides when the trigger is depressed how does it activate?  I don't know anything about welders electronics I am just trying to use electrical basics.If you could give me an idea of what it is supposed to be doing that would be great.Brandon!
Reply:What you are measuring from H2 to gnd is one half of your 208. When you measure H3 to gnd you are reading the same as H2 to gnd, through the solenoid coil winding. The solenoid has a 208 VAC coil. H2 supplies one half of the 208 and when CR1 relay ( on PCB ) closes H3 supplies the other half of the 208.When you take a voltage reading from H2 to H3 when CR1 closes you should get 208 VAC
Reply:Thanks guys.I have to go out to the shop to test it out again.  I know I was getting 125v from h3 to ground all the time nothing changed except it dropped a bit when I pulled the trigger.  And I always had 125v from h2 to ground trigger or no trigger. (I'm set up for 230v on the instruction sheet)  I know I have gas to the solenoid and it isn't getting through or clicking, everything else on the welder seems to be working fine.  Any guess on what it could be before I get a chance this weekend to go out and test it again?No leaks I have also tested that.  Also would there be a resistance spec for that solenoid?  From what everyone has said if the voltage is there it shold be working.Thanks again guys Brandon!
Reply:FORGET about measuring to ground !!!You have to measure across the load (solenoid) when triggeredAs has already been stated H2 to H3
Reply:I have also seen to much gas pressure on the inlet of the gas solenoid, which prevents it from opening.I believe the max input pressure on the valve is around 80 to 90 psi.
Reply:Originally Posted by PlasmanI have also seen to much gas pressure on the inlet of the gas solenoid, which prevents it from opening.I believe the max input pressure on the valve is around 80 to 90 psi.