Schneider Electric A9N26946

Schneider Electric A9N26946 is a miniature întrerupător de circuit (MCB) accessory belonging to the Acti 9 product range. Specifically, it is a shunt release with auxiliary status contact (MX+OF). The following are its key specifications:

Ordering Code: A9N26946

Product Series: Acti 9

Category: Miniature Circuit Breaker Accessory

Packaging Specification: 12 pieces per box, 72 pieces per carton

Electrical Parameters:

Tensiune nominală: 100-415V AC, 110-130În DC

Configurare contact: 1 deschis în mod normal (NU) contact and 1 în mod normal închis (NC) contact

Metoda de montare: Mounted on a 35mm symmetrical DIN rail, installed on the left side of the associated circuit breaker

Product Functions: When energized, the shunt release (MX) trips the connected circuit breaker or other modular devices. The auxiliary status contact (OF) is used for signal indication, feeding back the device’s operating status to the external control system. A mechanical status indicator is located on the front panel for visual inspection.

Applicability: Compatible with Schneider Electric product series including ID, C120, C60H-DC, and SW60-DC.

Practical Application Cases of Schneider Electric A9N26946 (MX+OF Shunt Release)

Schneider Electric A9N26946 is an MX+OF (shunt release + auxiliary status contact) accessory for the Acti 9 series. Its core value lies in the combined capability of remote forced tripping and real-time status feedback, making it widely applicable in electrical systems requiring emergency power cutoff and status monitoring.

1. Fire Alarm Linkage System in Commercial Buildings (The Most Typical Application)

Case Background

A 30-story office building is required to comply with GB 50116 (Code for Design of Automatic Fire Alarm Systems). The regulation mandates that non-fire-fighting power supplies (lighting, air conditioning, general-purpose sockets) must be automatically cut off in the event of a fire, with the power-off status fed back to the fire control room.

Solution

The A9N26946 accessory is installed on each C60H series miniature circuit breaker in the floor distribution boxes.

The MX coil is linked to the fire alarm control panel: when a fire alarm signal is triggered, the panel activates the MX coil (AC220V) via a relay, forcing the circuit breaker to trip and cut off the non-fire-fighting circuits.

The OF contacts (1NU + 1NC) are connected to the digital input (DIN) module of the fire alarm control panel, providing real-time feedback on the circuit breaker’s on/off status. This ensures that non-fire-fighting power supplies are disconnected, preventing secondary disasters.

The mechanical status indicator facilitates on-site inspection and verification.

Application Value

Complies with national fire safety codes and enhances building safety.

2. Emergency Stop (E-Stop) System in Industrial Production Lines

Case Background

A stamping production line in an auto parts factory faces risks such as equipment jamming and human misoperation. It requires a system to quickly cut off power to the entire production line in emergencies and feed back the shutdown status to the PLC system.

Solution

The A9N26946 accessory is installed on the ID series circuit breakers in the main distribution box.

The MX coil is connected to distributed emergency stop buttons (wired in series-parallel): when any emergency stop button is pressed, the coil is energized to trip the circuit breaker, cutting off the 380V power supply.

The normally open (NU) OF contact is connected to the PLC input module, triggering the production line shutdown program and displaying an “Emergency Stop” alarm on the HMI.

The normally closed (NC) OF contact is used to control the on-site audible and visual alarm, alerting personnel to evacuate the hazardous area.

Application Value

Provides millisecond-level emergency power cutoff response. Combined with status feedback, it prevents equipment damage and personnel injuries, complying with the ISO 13850 safety standard.

3. Precision Power Distribution System in Data Centers

Case Background

The UPS branch circuits of server cabinets in a large data center require support for remote maintenance power cutoff and automatic fault isolation, while monitoring circuit on/off status to ensure power supply continuity.

Solution

The A9N26946 accessory (compatible with DC110-130V) is installed on the SW60-DC series DC circuit breakers in the row cabinets.

The MX coil is integrated with the data center infrastructure management (DCIM) system: during remote maintenance, operation and maintenance personnel issue commands via the system to trigger MX tripping for safe operation.

The OF contact status is uploaded to the monitoring platform, displaying the power supply status of each branch circuit in real time and coordinating with the ATS for redundant switching.

The mechanical indicator enables quick on-site identification of faulty circuits.

Application Value

Enables remote operation and maintenance, rapid fault isolation, and visualized status monitoring, improving data center availability and O&M efficiency.

4. Safety Control System in Explosion-Proof Areas of Chemical Plants

Case Background

The reactor area of a chemical plant is classified as Zone 2 hazardous area, with risks of flammable gas leakage. The system must automatically cut off power in case of excessive gas concentration to prevent electric sparks from causing explosions, while feeding back the status to the central control room.

Solution

The A9N26946 accessory is installed on the C120 series circuit breakers in the explosion-proof distribution boxes.

The MX coil is linked to flammable gas detectors: when gas concentration exceeds the limit, the detector contacts close to energize the MX coil (AC380V) for forced tripping.

The OF contact is connected to the DCS system via safety barriers, achieving explosion-proof isolation and status upload, triggering alarms and emergency response procedures.

The mechanical indicator does not require a power supply, making it suitable for on-site status confirmation in explosion-proof environments.

Application Value

Features intrinsically safe design, eliminates potential ignition sources, and ensures that emergency measures are implemented through status feedback, complying with the GB 3836 explosion-proof standard.

5. Emergency Power Supply System for Medical Equipment in Hospitals

Case Background

Areas such as operating rooms and ICUs in a Grade-A tertiary hospital require automatic switching to UPS power supply in the event of mains power failure or emergencies, while cutting off power to non-critical equipment and monitoring the switching status.

Solution

The A9N26946 accessory is installed on the C60H-DC circuit breakers of non-critical circuits (de ex., general lighting, office sockets).

The MX coil is linked to the UPS system: when mains power is interrupted, the UPS triggers MX tripping to cut off non-critical loads, ensuring power supply to medical equipment.

The OF contact is integrated with the hospital building automation system (BAS), monitoring circuit status in real time to facilitate facility management.

The mechanical indicator helps medical staff quickly determine the power supply status.

Application Value

Prioritizes power supply to life-support equipment, enables visualized status monitoring, and improves the hospital’s emergency response capability.

6. DC Side Safety Protection System for PV Inverters

Case Background

The DC side of inverters in a distributed photovoltaic power station requires remote power cutoff during maintenance or faults to prevent arc hazards, while feeding back the status of DC switches.

Solution

The A9N26946 accessory (compatible with DC110V) is installed on the DC circuit breakers in the combiner boxes.

The MX coil is integrated with the PV monitoring system: remote maintenance commands or fault signals trigger MX tripping to isolate the DC side.

The OF contact status is uploaded to the monitoring platform, confirming that the DC side is de-energized to ensure the safety of maintenance personnel.

The mechanical indicator facilitates on-site confirmation and prevents misoperation.

Application Value

Enables remote safe isolation and visualized status monitoring, complies with PV power station safety operation procedures, and reduces the risk of electric shock.

7. Intelligent Control System for Hotel Guest Rooms

Case Background

A hotel chain needs to implement guest room power management (de ex., automatic power cutoff after guest checkout) and energy consumption monitoring, while feeding back room power supply status to the hotel management system.

Solution

The A9N26946 accessory is installed on the C60 series circuit breakers in the floor distribution boxes.

The MX coil is linked to the property management system (PMS): when a guest checks out, the system automatically sends a command to energize the MX coil for tripping, cutting off power to the guest room.

The OF contact uploads the power supply status to the PMS for energy consumption data statistics and energy management optimization.

The mechanical indicator facilitates quick inspection by engineering staff.

Application Value

Achieves automated energy conservation and visualized status management, reduces operational costs, and improves management efficiency.

Summary of Core Application Points

Product Selection and Application Notes

1. Compatibilitate: Suitable for Schneider Electric series including ID, C120, C60H-DC, and SW60-DC. Installed on the left side of the circuit breaker, mounted on a 35mm DIN rail.
2. Voltage Range: AC100-415V / DC110-130V. The control circuit voltage must match the coil rated voltage.
3. Wiring Specification: The MX coil is connected to terminals C1/C2. The OF contacts are connected to terminals C2-12 (NU) / C2-14 (NC).
4. Safety Design: A circuit breaker or fuse must be connected in series with the MX coil for overcurrent protection to prevent coil burnout due to short circuits.