How to choose the appropriate shunt specification?

Our shunt specifications offer a variety of options, differentiated based on the current range they need to support in practical applications. For example, a 12V battery pack with a maximum output power of 2400W requires a shunt capable of supporting a maximum current of 200A. The table below outlines the specifications and their corresponding current ratings: 

Different shunt specifications use varying materials, and larger specifications can withstand higher currents. However, simply choosing the largest specification is not the optimal approach. A large-capacity shunt can also monitor small currents starting from zero, but it has a few drawbacks.

1. Higher cost:​ The use of more materials, such as brass, increases the cost.

2. Different resolution compared to smaller shunts:​ Resolution can be understood as the scale on a ruler. A ruler that measures 0-750 meters (TCS500) and one that measures 0-75 meters (CS50) will have different smallest gradations. Some people confuse resolution with accuracy. If someone purchases a 500A shunt to monitor a current that never exceeds 30A, they might find that the minimum current change displayed is around 0.1A. For low-current applications, 0.1A is a relatively coarse gradation. This is not about accuracy. If a 30A or 50A shunt were chosen, this wouldn't be an issue, as the gradation would be 0.01A.

Therefore, the proper selection method is:

1. Calculate the maximum output current​ of the battery in your application scenario.

2. Based on this current, leave an appropriate margin​ and select the most suitable shunt specification.

This will help you choose the shunt specification that best fits your needs.