How to Set the Load Settings on an ACB?
Air Circuit Breaker (ACB) is an essential component in electrical systems that protects the circuit from
- Overload and
- Short Circuit.
The ACB configuration must be done appropriately to ensure the system’s safety and efficiency.
Today, we’ll talk about how to set 80% load & what parameters should be considered.
Ir (Overload Protection Settings)
Ir stands for Overload Protection, and it is set as a percentage of load current.
For an 80% load, IR = 0.8ln (In - nominal current).
Ex: If the nominal current (In) is 1000A, then Ir = 0.8 x 1000 = 800A
TR (Time Delay For Overload Protection)
TR is the time after that the breaker will trip due to overload.
It is often expressed in seconds & adjusted based on the type of load.
If tr = 10s is selected, the breaker will trip if 800A current flows for more than 10 seconds.
ISD (Short Circuit Protection Settings)
ISD stands for Short Circuit Protection, and it is activated when a short circuit current is present.
It is typically configured as a multiple of IR, such as 5xlr (or) 10xlr.