TONEOHM 950 Plane Short mode

[GU19951]

Hi everyone,

I recently acquired a Polar Instruments Toneohm 950 to help track down PCB shorts, but I'm having trouble getting it to work correctly.

Right now, I am trying to locate a short on a power/ground plane. I have all 4 cables (Kelvin probes) connected properly to the board, but when I switch to Plane Short mode, the device refuses to move into the "active" mode.

Because of this, I'm unable to get any readings or trace the short.

A few details:

The probes and cables seem to be in good physical condition.

Connections to the board are solid.

The device powers on fine, but the Plane Short mode just won't trigger active status.

Has anyone encountered this issue before? Is there a specific startup/calibration sequence I am missing for the 4-wire plane short mode, or does this sound like a hardware fault within the unit itself?

Any manuals, schematics, or advice on how to properly initialize this mode would be greatly appreciated!

Thanks in advance,

[Kean]

I would suggest moving this to the Test Equipment section of the forum to get more eyes on it.
As the thread starter, you should have a MOVE TOPIC button at bottom left of the page.