HFX – Electrical Test Set


Hui Gardens HFX electrical test set is the fusion of several basic electrical things that I’ve built while making other electronic things. It combines my HF1 – 100W Resistor Box, HF11 – 2 Wire RTD Simulator, the most useful parts of the HF2 -24V Variable DC Power Supply and more! I decommissioned the mentioned prototypes and repurposed almost all the parts including wires and resistors.

The Hui Gardens HFX features the following:

  • 24V adjustable DC power supply from 4x AA batteries (easy access) to loop power 4-20mA transmitters
  • 100W resistors including a 270Ω (close enough to a 250Ω resistor) for HART communication
  • 10 turn 2W potentiometers to allow for RTD simulation and 4-20mA simulation
  • 10W shunt to allow for high current measurement
  • Relay to take input and switch loads on and off and allow triggering of a frequency counter to test timing
  • 0.75″ spacing standard between banana jacks for double banana leads

I wanted something that can carry my Fluke 87V multimeter and be useful for things I test on a regular basis. I took a design cue from some of the high voltage equipment I see that allows for the meter and test leads to be stored in one case. Having a separate lead bag is really cumbersome and is prone to getting lost. I really like the brass wingnut chassis ground aesthetic. If it’s good enough for a 120kV hipot, it’s good enough for me!

Housed inside a Nanuk 920 hard case with a cut aluminum panel kit, the Hui Gardens HFX is pretty tough. The big red toggle switch cover is a must, the Chairman Mao emblem is an especially nice touch, but the best part is the custom 3d printed nameplate in brass.