Phase failure sensor CZF-B contact: 1Z, I=10A, 2 modules

Phase failure protection relay – reliable motor protection

This phase failure relay, catalog number CZF-B, is a key element in protecting three-phase powered electric motors. Its function is to monitor the presence of voltage in each phase and detect voltage asymmetries that can lead to motor damage. The device is particularly useful in industrial and commercial installations where motor failure can generate significant costs and downtime.

Functionality and application

CZF-B reacts to voltage loss in any phase or to the occurrence of a voltage asymmetry exceeding the permissible threshold (55V). In such situations, after a short delay (4 seconds), the circuit is disconnected, protecting the motor from potential damage. This delay minimizes the risk of unnecessary motor shutdown in the event of momentary voltage drops. After the correct power conditions are restored, the device automatically allows the motor to restart. This ensures continuity of operation and minimizes the risk of downtime.

The device is mounted on a 35 mm rail and occupies 2 modules, making it easy to integrate with existing switchgear. Screw terminals provide a secure and durable connection of wires with a cross-section of up to 2.5 mm². The status of the power supply is monitored by an LED in the circuit of each phase.

Key features and benefits

• Protection against phase failure: effectively protects motors from damage caused by the absence of one of the supply phases.

• Voltage asymmetry detection: protects against the negative effects of uneven phase loading, which extends the life of the motor.

• Adjustable shutdown delay: prevents accidental motor shutdown during short-term power disturbances (4 seconds).

• Automatic return to work: after the voltage stabilizes, the device automatically allows the motor to restart without manual intervention.

• Compact dimensions: 2 modules allow for easy integration with existing electrical installation.

• Simple installation: mounting on a standard 35 mm rail facilitates installation and servicing.

• Durable construction: ensures reliable operation in harsh industrial conditions (operating temperature: -25°C to +40°C).

• Maximum load current 10A: allows use in a wide range of applications.

• 1NO switching contact: provides flexibility in connecting external signaling or control devices.

The device is characterized by a voltage measurement range of 140 to 270V, a maximum permissible time delay in the event of a power failure of 4 seconds, and a minimum adjustable time delay in the event of a power failure also of 4 seconds. The maximum load current is 10A, and the number of changeover contacts is 1. The device has a height of 90 mm and a depth of 65 mm.

The device does not require an external power source, which simplifies installation and reduces operating costs. It is a solid and reliable solution for anyone who cares about the safety and efficiency of their electric motors.