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- Give me the steps for example of choosing MCB for (light + socket + Air Condition+ Motor) - Suppose the data (values), if it shoud come clearly with the load.
Calculate the Actual Load current considering future possible load.
Add twenty five percent as safety factor.
Check the available size of MCB above calculated Ampere rating.
For. eg. calculated load is thirteen ampere and future load on that circuit may be twenty percent of load, then total load will be fifteen point six. After considering the safety factor of twenty five percent total ampere will be ninteen point five.
The available size above calculated load is twenty ampere.
In case of motors or inductive load, the current during starting may go high above one hundred fifty percent, hence the MCB rating shall consider starting current. In that case the current with safety factor will be above twenty three ampere and available next size of MCB will be thirty or thirty two ampere.
It is based on load current. For example if air condition isA then we can use MCB above thanA that may beA or somewhat little higher.
