The Difference Between 4 and 6 Wire Load Cells.

If you use Load Cells regularly you will have come across both 4 wire and 6 wire load cells. So, what is the difference between 4 wire and 6 wire load cells?

Each wire has a name, both 4 wire and 6 wire load cells have +input, -input, +signal and –signal wires. A 6 wire load cell will also have a +sense and a –sense wire which are sometimes referred to as +reference and –reference.

When a load cell is in use, the cables will measure through resistance. The length of the cable will make a difference to the resistance being measured, this is where the 6 wire has the advantage: the 6 wire load cell is used as the Sense wires compensate for the voltage change when the length of the wires is changed.

About 4 Wire Load cells

4 wire load cells are supplied ready calibrated and it is recommended that you do not cut the wires during use, if they are too long it is better to coil them round. This is because they have been factory calibrated to provide accurate readings with the wires at this length.

When connecting a 4 wire load cell to a junction box and then the junction box to a weight indictor it is best to use a 6 wire load cell cable  for the junction box to weight indicator connection this will help to compensate any voltage drops during the length of the cable between them.

When connecting a 4 wire load cell to a 6 wire system it is necessary to use two bridge wires to ensure a proper connection. These wires need to be connected between the –sense and –input and the other bridge wire from the +sense to the +input.

About 6 wire load cells

Because 6 wire load cells have a +sense and – sense wire to measure the actual excitation voltage over different wire lengths the wires can be cut if necessary without compensating the functionality of the load cell. 6 wire load cells do not rely on the pre factory calibration to be able to function.

The sense wires of the 6 wire load cell can be connected to the sense terminals of the weight indicator to measure and adjust the amplifier on the actual voltage of the load cells.

When connecting a 6 wire load to a 4 wire system, the sense wires should be connected to the same place as the input wires. The +sense should be connected with the +input and the –sense should be connected with the –input.

Load Cells from Variohm

Variohm can offer a comprehensive range of load cells from our suppliers Zemic and Vishay. Popular applications for load cells include on board weighing systems and platform scales.

Our load cell categories include:

·        Single point load cells

·         Bending beam load cells

·         Compression load cells

·         S-type load cells

·         Shear beam load cells

·         Dual Shear beam load cells

·         Pancake load cells

·         On board load cells

·         Miniature Load Cells

·         Load Cell Amplifiers

·         Miniature and Subminiature Load Cells

For more information on our products take a look at our Load and Force product page or co...