For circuit breakers specification MUST suitable with installation condition and needed.Main switchboard is the main power supply distribution for factory or building.This unit is a key for entire electrical power supply distribution.
Circuit breaker feed the high volume of voltage for all equipment and machine.It also have a high value of short circuit current due to proximity of low voltage supply and size busbar for conveying the high current.
So we need carefully and detail understanding about circuit breaker before choose the circuit breakers for main switchboard application.This time i want share some information about criteria and specification circuit breaker for main switchboard.
Circuit Breaker specification for main switchboard
These circuit-breakers are suitable for main switchboard and designed for high current.The main factor must have are :
1) Circuit breaker able to protect for high current incomers and feeders power supply.
2) It must remain closed connection when short-circuits happen.The purpose is to let the downstream circuit breaker cut off the faults.
Circuit breaker function is normally used the time delayed basis. It used the 2 common method such as Electro Dynamic Withstand (EDW) and high thermal withstand characterised by a short time.
Important information for suitable circuit-breakers
Below i listed some criteria for circuit breaker that suit with MSB application :
- They must comply with standard BSEN 60947-2,
- It have a high breaking capacity lcu from 40 to 150 kA,
- Minimum spec with a nominal rating of 1000 to more than 5000 Ampere,
- Must a high lcw from 40 kA to 100 kA — 1 sec
- Include with high electrodynamic withstand (EDW),
- Must have a stored energy operating mechanism allowing source coupling.
- Must have a shunt trip function and can synchronize with OCR and EFR
We must take a serious note about choosing and sizing the circuit breaker for MSB because if wrong judgment and not suitable with application,it will cause a serious damage and more worst can cause serious injury or death for user or workers.
For more information about specific circuit breaker,please refer to electrical engineer or electrical consultant.They have a information and will guide to install the right circuit breaker for your power supply switchboard.