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By GTBecker
#191755
The BOB-13281 (and BOB-13878) Load Sensor Combinator is designed to combine four 3-wire half-bridge load cells like the SEN-10245 and similar devices found in common bathroom scales. I have not found any discussion that helps use the Combinators with 4-wire full-bridge load cells like SEN-13329 and others. Fortunately, it's not difficult: within reason, any number of identical 4-wire load cells can simply be paralleled.

The Combinators don't make it obvious but, for four 4-wire load cells, two pairs of two same-color wires can be soldered in appropriate holes to parallel the sensors. Each pair of the small wires fit easily in the corresponding hole - and two or three load cells will be easier - but six sensors (requiring three wires in each hole) will be more challenging. Each load cell wire should be connected to either the same-color GRN-, WHT-, BLK-, or RED-labeled hole along the Combinator edge - or to the R- (Combinator v1.0) or C-labeled (v1.1) holes - in red-green-white-black order. If you don't use the RJ-45 connector you can also connect to appropriate holes there.

If you do use the RJ-45 connector, note that the pinout is reversed at the other end of the Cat5 cable, i.e. RJ-45 pin 8 (Red) on the Combinator is pin 1 at the other end. See the attached images.
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