---
lang: "en"
title: "FF-CKF-B Three-phase asymmetry and sequence monitor"
sku: "FF-CKF-B"
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brand: "MARCOM S.r.l."
end_of_life: "false"
---

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FF-CKF-B three-phase asymmetry and sequence monitor

## Three-phase asymmetry and sequence monitor

CKF
With fixed voltage asymmetry actuation threshold.
Purpose
The three-phase and sequence monitor is designed to protect electric motors from voltage drop in at least one phase or voltage asymmetry between phases, which could damage the motor, with additional protection of the motor's direction of rotation in case of phase change before the monitor.

 

## Operation

A voltage drop in any phase or voltage asymmetry between phases above the fixed activation threshold causes the motor to shut down. Motor shutdown occurs after a 4-second delay, which prevents accidental motor shutdown caused by an instantaneous voltage drop. The motor restarts automatically when the voltage increases by ~5V above the activation voltage (i.e., approximately the value of the voltage hysteresis). When these disturbances occur, it is not possible to start the motor. In case of a change in the phase sequence, before the monitor, which causes a change in the motor's direction of rotation (in relation to the one primarily set), it is signaled by a red LED along with the impossibility of starting the motor. Reconnection is possible after returning to the correct phase sequence.

 

## Technical data

Power supply 3 × 400 / 230V + N
Current load <10A
Power supply / correct phase sequence signaling green LED
Inappropriate phase LED signaling red
Activation voltage asymmetry 45V ~
Hysteresis 5V ~
Shutdown delay 4 sec
Power consumption 1.6W
Operating temperature -25 ÷ 40 ° C
Connection OMY 4 × 1mm²; 2 × 0.75mm², l = 0.5m
Dimensions 50 × 67 × 26mm
Fixing with two screws to the base

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Source: https://shop.marcomweb.it/en/protections/ff-ckf-b-three-phase-asymmetry-and-sequence-monitor

MARCOM S.r.l. — a trusted supplier for industrial automation and building automation.