The Project

When working on the KMR Tiny Switch I needed a way to test the current capacity of the switch. I could either guess, send it to someone else, or build my own load tester....I decided to build my own.

Design Goals

  1. Should be cheap. I won't use this a lot and I don't want to spend much money on it.
  2. Its load should be variable. I want to be able to test a variety of loads.

Things needed

  1. A bunch of 2 ohm 100W resistors
  2. Some sort of port to allow connecting the resistors in different ways to get different dummy loads
  3. A container for all this madness.

The Story

I ordered some 2ohm 100W resistors from Amazon and a collection of banana terminals and plugs for a combined of $34.83. Combining these resistors in different patterns (parallel and serial) I should be able to create a wide variety of loads. The idea is to wire up modules to the banana terminals and then use jumper wires to modify the configuration.


The resistors are riveted to a peice of aluminum channel that I found on the side of the road from a lighting fixture. I may need to add more heat syncing or a fan.

Next Steps

  • Finish assembling the chassis.
  • Wire up the resistors to the terminals
  • Create jumper wires
  • Verify resistance using a multimeter in various configurations

The Results