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ABB MCCB selection guide

Choosing the frame size, trip unit and accessories for a moulded case circuit breaker.

This page was a price list

The legacy version of this page published a price list. Prices are not reproduced here: brief §30 requires commercial data to come from supplied current sources, and the legacy figures carried no validity date. Send us your requirement for a current quotation.

Step one: frame size

The frame size sets the maximum rating available in that body. Choosing a frame that is too small removes the option of a larger rating later without changing the device.

Step two: trip unit

A thermal-magnetic trip unit is fixed in ratio; an electronic trip unit allows the settings to be adjusted. Adjustability is what makes coordination practical on a large installation.

Step three: breaking capacity

The breaking capacity must exceed the prospective fault current at the point of installation. This is where under-specified boards fail, and it is not visible until a fault occurs.

Step four: accessories

Auxiliary contacts to signal the device state to a control system

Shunt trip for remote or interlocked tripping

Undervoltage release where a supply loss must trip the device

Rotary handles or motor operators where the device is inaccessible or must be operated remotely

What to send for a quotation

The single-line diagram or a list of ways with ratings, the fault level at the board, and any control requirements.

Need help with a specification?

Call 09678 566 000 or email info@impress.com.bd and we will work through the requirement with you.


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