Calculation method of ammeter multiple after using shunt

For motor test measurements, a current meter is often equipped with multiple shunts to solve the required measurement accuracy over a large measurement range. At this point, all the shunts used are required to have the same voltage drop as the rated ammeter, for example 75mV. Thus, after the shunt is selected, the full scale of the ammeter is the rated current of the selected shunt. The multiple of the ammeter (ie, the number of currents per dial of the dial) is the total current of the shunt divided by the total number of dials.

Shunts for DC current measurement are available in slotted and non-slotted versions. The shunt has a manganese-nickel-copper alloy resistance bar and a copper strip and is plated with a nickel layer. Its rated voltage drop is 60mV, but can also be used as 75, 100, 120, 150 and 300 mV.

Slot-type shunts are rated for the following types: 5 A, 10 A, 15 A, 20 A and 25 A

Non-slot shunts are rated from 30 A to 15 kA standard intervals.