Opening the Circuit Breaker

@experts: Topic shared between DOCA0284 and DOCA0285, with profiling; indicate if comments do not apply to both guides

To open the circuit breaker, the circuit breaker must be closed (I).

NOTE: An opening order always takes priority over a closing order.

The following table presents the different ways to open the circuit breaker.

Opening type	Accessories	Opening action
Mechanical	–	Press the opening pushbutton on the front of the circuit breaker. This opening action is possible at any time.
Automatic	MN undervoltage release, with or without MN delay unit	The MN undervoltage release opens the circuit breaker automatically in the case of voltage drop.
By external pushbutton	External pushbutton wired by customer One of the following accessories: MX opening voltage release MN undervoltage release, with or without MN delay unit	Press the external pushbutton which is connected to the MX opening voltage release or to the MN undervoltage release via the customer terminal block. When the MN undervoltage release is connected to the MN delay unit, the circuit breaker opens with the corresponding time delay.

Opening type

Accessories

Opening action

Mechanical

–

Press the opening pushbutton on the front of the circuit breaker.

This opening action is possible at any time.

Automatic

MN undervoltage release, with or without MN delay unit

The MN undervoltage release opens the circuit breaker automatically in the case of voltage drop.

By external pushbutton

External pushbutton wired by customer
One of the following accessories:
- MX opening voltage release
- MN undervoltage release, with or without MN delay unit

Press the external pushbutton which is connected to the MX opening voltage release or to the MN undervoltage release via the customer terminal block.

When the MN undervoltage release is connected to the MN delay unit, the circuit breaker opens with the corresponding time delay.