Conditions when there is a shutdown due to various reasons causes darkness or stoppage of work. When the system resumes, there are always voltage transients at the instant of resuming. That means voltage exceeds a certain limit. For example, in any of the system transient voltage of around 280V during resuming while the instruments in that system can sustain only 230V which causes malfunctioning or causes damage to equipment. To avoid this situation, an automatic stabilizing contactor is helpful which continuously monitors the incoming voltage with the standard voltage. This can be achieved with the help of comparators. if the incoming voltage is in the specified range then a coil pulls the plunger. Generally maximum industries uses stabilizers which requires some time (1-2 sec) to stabilize the transient voltage. In any case the stabilizer fails to stabilize the voltage and has this particular setup after the stabilizer then it will help to protect the stabilizer as well as the consumer's equipment. Main motto of this setup to check the power quality of the input supply and maintain the health of your machines.
Another system built in this setup will check the status of current and using bimetallic if the current exceeds the limit. Bimetallic strip removes relay of coil that causes the plunger to remove from contactors and act as a circuit breaker. If in any condition the frequency changes above tolerance value the zero crossing detector is not able to compare the voltage which helps the system to secure from the effects of frequency change.
Power consumption of the system is much less as we are converting the AC supply system to DC. This system does both the work of an MCB and stabilizer. We can implement monitoring system in it ,just introducing sensor and IoT. This system does not require any external power supply. It will take whatever the input as input source so that power consumption is much lower.
The illustration shows that plungers and contactor are uses to switch the input so it also removes the ICTP in the distribution box. By pressing a switch the system gets connected and bimetallic strip uses to monitor current.