Accessories

The spring-charging motor automatically charges the spring mechanism for closing the circuit breaker and also recharges the spring mechanism when the circuit breaker is in the ON position. Instantaneous reclosing of the circuit breaker is thus possible following circuit breaker opening. The spring-mechanism charging handle is used only as a backup if auxiliary power is absent.

The spring-charging motor is equipped as standard with a limit switch contact (CH) that signals the charged position of the mechanism (springs charged).

Spring-Charging Motor (NW)

Spring-Charging Motor (NT)

Maximum Wire Length—The inrush currents for these devices are approximately 200 VA. When low supply voltages (12, 24 or 48 V) are used, the maximum allowable wire length is dependent on the voltage and the wire size.

Shunt Trip (MX1) and Shunt Close (XF)

Shunt Trip (MX1): When energized, the shunt trip instantaneously opens the circuit breaker. The shunt trip may be energized continuously or intermittently.

Shunt Close (XF): Remotely closes the circuit breaker if the spring mechanism is charged. The shunt close may be energized continuously or intermittently.

Communication versions of the MX1 and XF are available for direct connection via the circuit breaker communication module (BCM).

Second Shunt Trip (MX2)

This function opens the circuit breaker via an electrical order.

• Shunt trip (MX2, second MX) or,

• Undervoltage trip (MN)

  — Instantaneous trip

  — Fixed undervoltage trip (time delayed) or,

  — Adjustable undervoltage trip (time delayed)

As shown in Wire Diagram for the Remote Tripping Function below, the delay unit (installed outside the circuit breaker) may be disabled by an emergency off button to obtain non-delayed opening of the circuit breaker.

When energized, the shunt trip (MX1 or MX2) instantaneously opens the circuit breaker.

The undervoltage trip (MN) instantaneously opens the circuit breaker when its supply voltage drops to a value between 35% and 70% of its rated voltage.

If the undervoltage trip is not energized, it is impossible to close the circuit breaker, either manually or electrically. An attempt to close the circuit breaker produces no movement of the main contacts. Closing is allowed when the supply voltage of the undervoltage trip reaches 85% of rated voltage.

Wire Diagram for the Remote Tripping Function

Time-Delay Module for Undervoltage Trip (MN)

To eliminate circuit breaker nuisance tripping during temporary voltage dips (micro-breaks), operation of the undervoltage trip (MN) can be delayed. This function is achieved by adding an external delay unit (either adjustable or non-adjustable) to the undervoltage trip (MN) circuit.

Ready-to-Close
Switch (PF)

The ready-to-close position switch indicates that the following conditions are met and the circuit breaker can be closed:

• The circuit breaker is open.

• The closing springs are charged.

• There is no standing closing or opening order.

Electrical Closing Push Button (BPFE)

Located on the front panel of the circuit breaker, this push button carries out electrical closing of the circuit breaker, taking into account all of the safety functions that are part of the control/monitoring system of the installation. The push button is installed on the control circuit of the shunt close, and connects to the communicating shunt close module (XF-COM). Terminal A2 of XF-COM is used to remotely close the circuit breaker.

• Remote reset (RES): following tripping, the remote reset (RES) resets the overcurrent trip switch (SDE) and the mechanical indicator. (Voltage rating: 110/130 Vac and 200/240 Vac.) RES is not compatible with an additional overcurrent trip switch (SDE2).

• Automatic reset after fault-trip: following tripping, a reset of the mechanical indicator (reset button) is no longer required to enable circuit breaker closing (factory adjustable only).

The rotary-type auxiliary switches are directly driven by the trip mechanism when the minimum isolation distance between the main circuit breaker contact is reached.

Auxiliary Switch (OF) with Four Contacts for MasterPact NW Circuit Breaker

MasterPact NT Aux Switch (OF) with One Contact

Overcurrent Trip Switch (SDE)

Circuit breaker tripping due to a fault is signalled by a red mechanical fault indicator (reset) and one overcurrent trip switch (SDE).

Following tripping, the mechanical indicator must be reset before the circuit breaker may be closed. An additional overcurrent trip switch (SDE2) is supplied as an option and is not compatible with the remote reset (RES).

Connected/Closed Switch (EF) NW only

This switch combines the “device connected” and “device closed” information to produce “circuit closed” information. The connected/closed switch (EF) is supplied as an option and must be used with an additional auxiliary switch (OF) and fits into its connector (it is not available for ring terminals).

Cradle Position Switch (CE, CD, CT)

Additional Actuators for Cradle Position Switches on MasterPact NW Circuit Breakers

A set of additional actuators may be installed on the cradle to change or add the functions of the cradle position switches. Each standard actuator can be replaced by any other actuator to change the function of the cradle position switch.

Cradle Position Switch Actuators
Actuator for up to Three CE Switches (standard)		Actuator for up to Three CD Switches (standard)		Actuator for up to Three CT Switches (standard)

Push Button Lock

A transparent cover blocks access to the push buttons used to open and close the device. It is possible to independently lock the opening button and/or the closing button. The push buttons may be locked using:

• One to three padlocks: 3/16–5/16 in. diameter, not supplied

• A wire seal

• Two screws

Open Position Key Lock

Open Position Padlock Provision

The circuit breaker is locked in the off position by physically keeping the opening push button pressed down using one of the following:

• One to three padlocks: 3/16–5/16 in. diameter, not supplied

• Key locks: One or two Kirk^® key locks (keyed alike or differently) are available for UL Listed/ANSI Certified circuit breakers; for IEC Rated circuit breakers, Ronis^®, Castell^®, or Profalux^® key locks are available

Keys may be removed only when locking is effective. The key locks are available in any of the following configurations:

• One key lock

• One key lock mounted on the device + one identical key lock supplied separately for interlocking with another device

• Two different key locks mounted on the circuit breaker for double locking

A locking kit for installation of one or two key locks may be ordered separately.

Disconnected Position Locking Provisions

The circuit breaker can be locked in the disconnected position by key interlock (optional) or padlock (standard). The key interlock is on the cradle and accessible with the door locked.

• Kirk key interlocks are available for UL/ANSI circuit breakers; for IEC circuit breakers, Ronis, Castell, or Profalux key locks are available. Key is captive when key interlock is unlocked.

• Locking on disconnected, test, and connected positions is optional for IEC circuit breakers and standard for UL/ANSI circuit breakers.

Door Interlock (NW)

The door interlock prevents the compartment door from being opened when the circuit breaker is in the connected or test position. If the circuit breaker is put into the connected position with the door open, the door can be closed without disconnecting the circuit breaker. For greater protection, this interlock can be used in conjunction with the open door racking interlock.

The racking interlock is standard for UL and ANSI circuit breakers, and optional for IEC circuit breakers. It prevents insertion of the racking crank unless the OFF push button is pressed.

The optional cable door interlock prevents the compartment door from being opened when the circuit breaker is in the closed position. This kit includes:

		Kit Contents
		A	Panel Interlocking Plate
		B	Circuit Breaker Interlocking Plate
		C	Interlocking Cables
		D	Bolts with Washers
		E	Guide-Bolt with Washer
		F	Interlocking Bracket
		G	Calibration Tray

Source changeover interlocks allow mechanical interlocking between two or three circuit breakers (fixed and drawout).

Source Changeover Interlocks
Two NW Circuit Breakers Interlocked Using Rods		Three NW Circuit Breakers Interlocked Using Cables

Interlocking Two Circuit Breakers

• Interlocking Two Mains Using Rods

• Interlocking Two Mains Using Cables

Interlocking Three Circuit Breakers Using Cables

• Interlocking Two Mains and One Generator

• Interlocking Two Mains and One Tie

• Interlocking Three Mains

Open Door Racking Interlock

The racking interlock prevents racking in the circuit breaker when the door is open. (Insertion of the circuit breaker racking crank is not possible when the compartment door is open.)

Automatic Spring Discharge Mechanism

The automatic spring discharge mechanism is standard for UL and ANSI circuit breakers, and optional for IEC circuit breakers. It releases the closing spring energy when the circuit breaker is moved from the disconnected position to the fully withdrawn position.

The cradle rejection feature (standard) ensures that only the properly designated circuit breaker or switch is matched with the selected cradle assembly.

Cradle Rejection Kits

Cradle Rejection Kit Contents

Rail padlocking is standard for UL, ANSI, and IEC cradles. When used in combination with the disconnected position locking device, rail padlocking prevents the movement of the circuit breaker from the disconnected position to the fully withdrawn position when the padlock hasp is pulled out and locked.

Mechanical Operation Counter (CDM)

The mechanical operation counter (CDM) registers the total number of operating cycles. One CDM is installed per circuit breaker.

The shutters automatically block access to the main disconnects when the circuit breaker is in the disconnected, test, or fully withdrawn position. The shutter lock is used to prevent connection of the circuit breaker or to lock the shutters in the closed position.

Not available on cradles with ArcBlok™ technology.

UL® Circuit Breaker Shutter

Shutter Lock

These door escutcheons provide a frame and seal for the circuit breaker.

Door Escutcheons
Door Escutcheon (NW Fixed)	Door Escutcheon (NW Fixed)

Transparent Cover (CCP)

The cover is hinged-mounted and locked with a milled head, and is designed to be installed on the door escutcheon.