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Old Fluke Multimeters
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AVGresponding:
The manual for this meter is readily available from the usual suspects online, and contains the schematic and board layout.
bdunham7:

--- Quote from: NoisyBoy on January 23, 2023, 06:31:47 am ---Great suggestion, that was my next step. My 3631A, which I never use, may be ideal for the job. While the +5V is quite clear, any suggestion where the +15 and -15 should be connected to on the board?

--- End quote ---

First you have to determine which model of 8000A you have--the 'options' such as Lo-ohms and 10A or even the milliamp-second pulse energy feature all are actually revisions of the entire instrument to varying degrees.  However, if you have a non-battery model, you likely have three larger capacitors on the left rear of the board that all have a common rail on the outside.  The other ends of those--toward the transformer--should be your +5, +15 and -15 rails, in order from the back.

How have you verified that T1 primary is open?  There are two windings used in parallel in the 115V configuration, so it seems unlikely that two windings would both break.

Manual: https://xdevs.com/doc/Fluke/8000a.pdf

Typical PSU: 
NoisyBoy:
Thank you so much for the helpful response.  I have been working off the service manual on the meter for a couple days now, on page 4-5 step 15, they refer to J4-25 and J4-27, which corresponds to the circled number on the schematics, the challenge is I have no idea where they are referring to on the actual board.  If I apply DC power to the ends of C17 and C18, it appears I have to apply 19-20V instead of the 15V based on step 14 of the troubleshooting guide.  But at least I can find those connection points at the end of the two caps. 

I was able confirm connectivity between the plug to one end of S12, and confirm the fuse F1 is fine, as well as S12 (the power switch) working correctly after I deox it.  But from the end of S12, through the primary to the other end of the plug, it is measured open.  Could the internal thermal fuse cause the problem?  Given the external fuse F1 is intact, I am surprise the thermal fuse would fail on the primary end.
bdunham7:
If you measure right at T1 what do you get?  They use solder bridges to rewire from 115 to 230V operation, for 115V SB1 and SB3 are bridged and SB2 is open.  On mine if I measure from SB1 to SB3 I get 367.5 ohms.


NoisyBoy:
Hi, I checked that last night.  My unit matches your picture exactly, SB1 and SB3 are bridged and SB2 is open.  On my unit, SB1 to SB3 is wide open, that's what led me to think the primary failed.  The transformer looks perfect on the outside, no burn mark or sign of overheating.
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