SparkFun Load Sensor Combinator

The SparkFun Load Sensor Combinator is a bare PCB that combines four load sensors into a standard four-wire Wheatstone bridge configuration. If you open up an electronic bathroom scale, you’ll find a large rat's nest of wires. The Load Sensor Combinator was created to combine the 12 wires found in a bathroom scale into the standard four-wire Wheatstone bridge configuration.

This version of the SparkFun Load Sensor Combinator features a few changes that you specifically asked for! We updated the silk on the breakout to read "C/+/-" instead of "R/W/B" and moved the temperature sensor connector away from the standoff hole.

You can either use four individual load sensors or simply purchase an off-the-shelf bathroom scale and hack the combinator into it rather than trying to design a base to properly mount four load sensors.

If your amplifier and supporting electronics are more than a few inches away from the scale, an RJ45 footprint is provided. The four Wheatstone pins (E+/E-/S+/S-) as well as the shield pin are connected to twisted pairs within a standard cheap Ethernet cable. This allows the amplifier board to be placed many feet away from the scale itself.