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Minimum ohms for sa200 shunt coils

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8.5K views 8 replies 2 participants last post by  booneandbuck  
#1 ·
I have a 59 blue tint sa200 that I have completely rebuilt. I upgraded and replaced everything on the machine except for any of the coils. I've put about 350 hrs on the machine and haven't been able to get it to weld like it should. I set the rack on the punch marks and have not tried rolling it. I checked my shunts today and I'm getting 35.5-35.6 ohms. I've seen where they need to be around 41ohms but haven't been able to find a definite minimum that they can be. I'm thinking this could be some of my problems. What do you guys think?
 
#2 ·
Across the blue and brown wires coming out of your generator housing you should read approximately 40 ohms.
 
#4 ·
You'll need to check all the wires, most likely there is a wire touching somewhere. What kind of voltage do you have at the receptacle, and the welding lead studs?
 

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#6 ·
I'm sure a 59 is the same as a Red Face. This is all right from Kaye.
Red Face RPMs, Full load 1,450. High idle 1,550. Low idle 1,000.

You should have 90-volts DC at the receptacle on the front of the machine, and 66-volts DC at the welding lead studs at low idle. 88 to 95- volts at high RPM on the welding lead studs, and 125 to 130-volts DC at the receptacle.
 
#8 ·
Do you think that 35 ohms is too low for shunts?
Yes I do, but you should wait until duaneb55 sees this thread, he has forgotten more about working on these old girls than I'll ever know! :eek: