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Re: Miller del 200 no power out put

Ok so I was able to fire up the welder today with an oil pressure guage and with it warmed up at idle I am getting 20 psi at wide opened throttle I am getting 25 26 psi

Re: Miller del 200 no power out put

Ok thanks I will give that a try tomorrow

Re: Miller del 200 no power out put

either switch is bad, or engine has low oil pressure.
you can replace the switch with a pressure gauge and see what the oil pressure is or
figure a way to test the switch. I have a pressure regulator and a tee.
switch goes in one port and the other is plugged with a small hole.
Then you can raise and lower the pressure using air and adjusting the regulator.
Put ohm meter on switch and see if it will close or open. You have to have a small leak or the pressure on the switch will equal the supply pressure.
For a regulator to work correctly air must be flowing somewhere.

Re: Miller del 200 no power out put

Ok so I made sure I was getting 12 volts to the oil pressure switch which I am getting but with the engine running the oil pressure switch isn't allowing the 12 volts through un less I jump it with a wire.

Re: Miller del 200 no power out put

follow the wires, for anything to happen we need to get 12vdc from the battery to the brushes when the oil pressure switch closes or when we jump it so we don't have to run the engine. You have a bad connection, open flashing diode or broken wire.
measure from the pressure switch to ground. find wire 30 it should have 12vdc on it all the time when measured to ground. Then follow wire 31 from the other terminal up to D4. test D4 in diode test. If ok, you should have 12vdc on the diode with pressure switch jumpered. Wires 31 and 21 go to the flashing diode. wire 21 then goes to the center brush. With one meter lead on ground, you should be able to follow 30 to 31 to 21 and get 12vdc at each point with switch jumpered.
Rear slip ring should show shorted to ground, wire 33. Battery plus terminal to rear slip ring should read 12vdc all the time. If D4 tests open, don't hard jumper it.
If welder starts producing power it could damage the battery changer and the battery. D4 blocks excitation voltage from getting to the battery.
With pressure switch jumped and D4 jumpered you should get 12vdc to brushes.
rear set. If you get 12vdc to brushes with D4 jumpered. start engine and pull jumper right off, before engine reaches full speed. welder might come to life and produce power. D4 is a 3 amp 1000 volt diode. will be the smallest of the 8 diodes not on a circuit board. (1, 3A) (3, 50A) and (4, 150A).
Keep digging you will find it. Just follow the wires through the harness.

Re: Miller del 200 no power out put

I jumped the oil pressure switch and am getting no power at the brushes

Re: Miller del 200 no power out put

Ok will try and give that a try later today or tomorrow

Re: Miller del 200 no power out put

with everything connected and oil pressure switch jumpered. do you get 12vdc at the brushes. switch on but engine not running. Leave jumpered only long enough to get a meter reading. If you get 12vdc at brushes, start engine and see if pressure switch does close. then recheck for 12 vdc then see if you get AC at 28 and 29.
If no AC at 28 and 29 then we are not make any power. since all the diodes appear to test ok. If points back to a stator or rotor problem. rotors sometimes test good when stationary. but will open up under the force of spinning. A close inspection of the stator, looking for popped ties and discolored wires. Then check each winding to make sure they are not broken or shorted to ground. or each other. May have to disconnect them.

Re: Miller del 200 no power out put

I did these two test with the battery connected but the welder not running.

Re: Miller del 200 no power out put

Ok so I tested the 3 stud diodes and got a reading of .421 for the one on the left .423 for the middle one and .421 for the left one. When I switched the leads I got a reading of .OL for all 3. That was with negative on the diode and positive on the plate they are mounted to.

Re: Miller del 200 no power out put

Ok so I pulled wire 26 of and reversed the meter leads I got an .OL reading on all 3 tabs

Re: Miller del 200 no power out put

Ok Ill try that tomorrow

Re: Miller del 200 no power out put

reverse the meter leads and see if you get OL.
One more thing to try, unplug the wires to the brushes. tag them so you can put them back in the right place. Or note the wire numbers.
Get a battery and apply 12vdc in the correct polarity to the brush terminals.
See if any of the of the stator outputs have voltage. Monitor the current into the brushes. If very high or zero there is a problem with the rotor.
Motor needs to be running to spin rotor.
In your picture the other parts on the plate the diode block is bolted to are stud diodes. three feed the square 120 vdc plug. the forth on should be the flashing diode. Tests them all in both directions, looking for .4 and OL. May have to isolate the diode to get a good reading. If you unbolt any of them you will need to clean them and the plate. then install with fresh heat sink paste.

Re: Miller del 200 no power out put

Ok so I ran a diode test on the sr2 with wire 26 off. I went in a counterclockwise direction so the tab to the left I got 0.443 then the tab on the bottom I got 0.869 then the tab to the right I got 0.443. Here are the pictures https://photos.app.goo.gl/aJeov99VjXaTj8oW7

Re: Miller del 200 no power out put

Ok so I fired up the welder and pulled wires 28 and 29 off getting a reading of .026 volts of ac power on the sr2 block

Re: Miller del 200 no power out put

If you are reading wire 28 to 29 you should get a low reading. That is the excitation power supply winding in the stator. with 28 and 29 unplugged. start the welder and see if you have any voltage there. will be AC.
Unplug wire 26 then measure the diode in diode test mode. going around like in a circle. should measure around 0.4 and OL in reverse if you skip a terminal it will be 0.8 and OL. Look at the markings on the diode block. should be able to find DC+ and DC- on opposite corners. the other two corners will have the AC sine wave symbol.
28 and 29 go to the AC terminals and 26 and 27 to the DC. 26 should be neg.
wire 26 should read low ohm to case ground and 27 should read like a diode to the oil pressure switch. If you short the oil pressure switch this should give you 12dc on the exciter slip rings and flash the exciter. same thing should happen when the engine is started, the oil pressure should build, close the switch and apply 12 volts to the slip ring. then voltage should build. once excitation voltage is there the square plug should have voltage 115 to 120 dc volts at weld speed.
weld/ power switch should then select weld power or turn on the AC plugs.

Re: Miller del 200 no power out put

With wire 29 pulled off I am getting no reading at all with both wires on i get 1.0 to 1.2 ohms

Re: Miller del 200 no power out put

So I checked the SR2 and am getting a reading of 1.0 to 1.2 ohms

Re: Miller del 200 no power out put

Ok I found where the location is will try and test it tomorrow

Re: Miller del 200 no power out put

SR2 is a block with four tabs. contains 4 diodes in a bridge arraignment.
Should be bolted to a metal plate with 3 or 4 stud type diodes next to it.
Check the parts pages in the owner's manual for location.
SR2 is your excitation power supply. the stud diodes are for the 115 volt DC Square receptacle. you need t find SR2 and make sure it is ok and not open or shorted.

Re: Miller del 200 no power out put

Ok so I was able to test the slip rings and this is what I got Around 30.8 ohms from center ring to the right ring (towards engine) and 26.3 from center to the left ring (towards panel). I got no ohms reading from the center ring to case ground bolt. I was looking at the control boards and could not find sr2 or wires 28 and 29.

Re: Miller del 200 no power out put

Ok I will try and work on it tomorrow and see what I get.

Re: Miller del 200 no power out put

What you are reading does not make sense. So lets start at the beginning.
Lift the brushes off the slip rings, slip a piece of paper to insulate them from the brushes. Take you ohm meter and test from the center ring to the out side ones then to the case ground bolt. Should be no reading to ground. ring to ring should be low but not zero. Any reading to case ground from isolated slip rings is a shorted rotor.
Next find sr2. It is on a panel with 3 other diodes. find wires 28 and 29. the wires should read a near short. disconnect one wire and test the diodes. in the SR2 bridge diode. Next go to the 115 vdc plug perform a diode test across the plug. should be a lower value because you are reading 3 diodes in parallel. OL in reverse.
Next find the oil pressure switch. with the brushes still isolated. jumper the pressure switch and see if get 12vdc at 33 and 27. Exciter brushes. removed jumper and perform a diode test from center slip ring brush wire 27 to pressure switch wire 31. Negative meter lead on brush wire. If all the diodes test good and the coils are not open or shorted to frame. then we will try something else.

Re: Miller del 200 no power out put

Here is the link for the pictures of the voltmeter reading. https://photos.app.goo.gl/osmbto15rcXuaA9fA

Re: Miller del 200 no power out put

I used my voltmeter to test the power out of the ac and dc plugs and got a reading of 1.30vdc and 1.77vac for the ac power plug. This was with the welder at idle.