Phase sequence and phase failure sensor with adjustable voltage window CKF-320-TRMS

Advanced three-phase motor protection

The CKF-320-TRMS phase sequence and phase loss sensor is a reliable device designed to protect electric motors powered by a three-phase network. Its task is to monitor the voltage parameters in individual phases, reacting to irregularities that can lead to damage to the connected equipment. The device works well both in industrial installations and in home applications where ensuring safety and continuity of operation is key.

Versatile protection and diagnostics

CKF-320-TRMS not only detects phase loss but also controls the asymmetry of interphase voltages and phase sequence. This prevents incorrect motor starting, which could run in the reverse direction or be damaged due to uneven load. The built-in relay provides a quick response to detected threats, disconnecting the circuit and protecting the motor from more serious failures.

Precise TrueRMS measurement and threshold adjustment

The use of TrueRMS technology guarantees accurate voltage measurement even in disturbed power networks, which translates into reliable operation of the device in all conditions. The ability to adjust the lower (180÷220 V) and upper (240÷280 V) voltage thresholds allows you to adapt the sensor to the specific requirements of the installation and load characteristics. Voltage hysteresis at 5V prevents frequent on/off switching in the event of minor voltage fluctuations. Additionally, the delay in switching off in the event of asymmetry and phase loss (1÷10 s) and in the absence of a phase (1 s) minimizes the risk of accidental disconnection of the motor during short-term disturbances.

Mounting and signaling

The sensor is mounted on a 35 mm rail and occupies only 1 module (18 mm), making it easy to integrate with the existing electrical installation. Built-in LEDs indicate the device status: a green LED informs about correct power supply voltage, and a red one – about detected phase sequence error or other problem. In case of incorrect connection of the input wires, the diodes flash in the red-green sequence, warning against potential damage to the controller.