Coulomb Counting

Coulomb counting is a new feature that we introduced to the Pro-100 / 160 / 360 series controllers in software version 2.5.3. It uses the current sensor in the controller to measure the actual amount of energy used by the motor over time. One coulomb is defined as a current of one amp flowing for one second, and this can be related to the ampere hour capacity of the battery by the formula 1Ah = 3600 coulombs.

The coulomb counting feature allows you to set the capacity of your battery, and will then subtract coulombs as they are used, this provides an effective and accurate “fuel gauge” feature.

Coulomb counting is much more accurate than relying on battery voltage values, which can vary significantly depending on the current being drawn. Lithium batteries are a particular problem as they have a very flat discharge profile with only a small difference in voltage between full and empty. Coulomb counting is not affected by this as it measures the real energy that is actually used.

We have a supplement in our manuals section that describes the set-up and operation of this feature in more detail.