mkove electronics

Sense Lines

 

The most accurate method to monitor current into and out of a battery system is to use a current shunt.

 

A common shunt which is able to monitor engine starting is a 500 amp 75 millivolt shunt. The following table shows the millivolts that are produced for different amperages across this kind of shunt.

 

shunt voltages

 

As you can see the voltage that is being measured to provide a current reading is tiny. At less than a few amps most digital multimeters would not even show a reading between the two sense line. This is the reason that the MK70 uses a separate Sensor unit to read the sense lines near to the shunt as the longer the sense lines the more likely they are to provide an innacurate reading due to interference and other wires distorting the very low voltage values.