4‑Wire DMM Shorting Plug construction project
This was a quick project to construct a 4‑Wire shorting plug for my recently acquired Keithley 2015 benchtop THD Multimeter. The shorting plug in the photo above is the prototype for checking dimensions, board spacing, and operation. I designed the board and had it fabricated by OSH Park. The board dimensions are 1.25 x 1.25 inches using 1 oz copper and an ENIG (immersion gold) finish. The posts are spaced on a 0.75″ grid which should work with most 4‑Wire multimeters that use a standard 3/4″ banana plug spacing.
The next step is to order 4 gold plated banana connectors to reduce the thermal EMF (Seebeck Effect), caused by thermal differences between conductors of dissimilar materials.
Boards are shared on OSH Park. 4 Pin Shorting Board V1