The positive phase sequence is RYB, YBR, BRY rotates in the clockwise direction. If the stator of the motor receives a three-phase supply in the above-said phase sequence, then the motor rotates in the same direction for the three sets of order RYB, YBR and BRY base on design as labelled by the manufacturer. hence a phase sequence protection is required when the machine is not design to run counter clockwise or in both direction. some machines are design to run in only anticlockwise direction while some are design to run both clockwise and anti clockwise. if your machine is design to run both direction then you dont need this device. one of the function of this device, is to ensure that your motor does not run two direction but one.
phase loss protection....A phase loss is a very damaging event for a three-phase motor. It will cause a reduction in the power output from the motor which can cause stalls or an inability to start the motor - all while the motor draws excess current. This will cause the motor to overheat and quickly burn out. this device also ensure that there is no phase loss in the circuit and anytime there is a phase loss it will withhold the output supply that is main to energize the motor contactor until correction is made. thirdly this device offers voltage protection, for a 3phase system a normal voltage is 415volts hence, there can be low voltage or high voltage problem. the device monitors the voltage between the range of 370 volts to 420 volts anything higher or below will not be allowed to pass. TECHNICAL DATAcontact ralay rating 10amps 250vac resistive loadinsulation 100M ohmsdielectric strength 1500vacconsumed power 2vaambient temperature -10 degree C and +- 55 degree C HOW TO CONNECTthere is operating manual in the package for does that understood control, nevertheless a simple connection is to ensure that the device is correctly fixed to the terminal base if done wrongly, it can damage the device, connect L1 RED TO (6) AND LINE 2 YELLOW TO (5) AND LINE 3 BLE TO (8) then loop from (6) to (1) if you did that correctly (3) is your load'. if all the requirement have been met, live will go to terminal (3) and that's what you will use to complete your load contactor circuit for the contactor to close.