Function

Selective Main Circuit-Breaker series S 750 DR

ABB’s S 750 DR is used as a reliable group protec

tion device worldwide. S 750 DR is the right

choice when it comes to selectivity for critical

power application such as hospitals, airports and

data center. But also in residential application

SMCB technology has big advantages. In Germany

SMCB technology became the standard choice for

meter board application where the products

works as a group protection device for down stream circuits.

In order to avoid unauthorized manual switching

the S 750 DR. The S 750 DR is provided with an

integrated locking tab which makes it possible to

block the all poles simultaneously. 

The integrated locking tab locks the circuit-breaker in ON or OFF

position and can be additionally protected by a

padlock, wire seal or cable tie. When locked in ON

position, the protective function is maintained in

case of a fault: The blocked switch handle still

permits the tripping of the mechanism and open

ing of the contacts in case of overload or

short-circuit (trip-free mechanism). The indicator

shows “green” also in case of a fault with ON po

sition locked – giving you the certainty that power

is switched off.