FF CKF-BR phase loss and phase asymmetry relay 10A 1P 4s 40–80V

The FF CKF-BR phase loss and phase asymmetry relay is an electromechanical protection device designed to detect phase failure and phase imbalance in single-pole control circuits. Rated for a switching capacity of 10 A and operating within a voltage range of 40–80 V, the relay provides a fixed response delay of 4 seconds to avoid nuisance trips from short transients. It is intended for use in motor protection and in safeguarding three-phase systems where detection of missing phases or significant asymmetry is required.

Advantages

The device combines simple electromechanical reliability with straightforward installation into existing control circuits. Its single-pole design and compact footprint make it suitable for retrofitting into motor starters and control panels. The fixed 4-second response time reduces false triggers caused by brief voltage dips, while the 10 A switching capacity covers a wide range of control loads. The 40–80 V operating range ensures compatibility with common low-voltage control supplies.

Suitable for

• Protection of motors from phase loss and imbalance in industrial installations
• Monitoring three-phase equipment via a single-pole control circuit
• Integration into motor starters, contactor control circuits, and control panels
• Commercial and light-industrial systems using 40–80 V control supplies

Key specifications

• Function: phase loss and phase asymmetry detection
• Switching capacity: 10 A
• Poles: single-pole (1P)
• Operating voltage range: 40–80 V
• Response time: 4 seconds
• Actuation: electromechanical relay mechanism

How to use

Install the relay in the control circuit following the manufacturer’s wiring diagram and ensure correct connection to the monitored phase supply within the 40–80 V range. Mount the unit in a dry, vibration-free section of the control cabinet and secure appropriate terminal tightening to maintain reliable contacts. When powered, the relay monitors for phase loss and asymmetry; after a detected fault persisting beyond the 4-second response time, the relay will change state to interrupt the controlled circuit. Restore the supply and clear any faults before returning the equipment to normal operation.

Usage recommendations

Use the relay with appropriately rated contactors or circuit protection devices and verify compatibility with the control supply voltage. Periodically inspect terminals and mechanical condition as part of routine maintenance and replace the relay if contact wear or unreliable operation is observed.