GE prolec VR-1 Installation, Operation And Maintenance Manual

Also see for VR-1: Installation operation & maintenance

GEH-7299A: Installation, Operation and Maintenance Manualfor Type VR1™ Single-Phase, Step Type Regulatorsprolec.energy/prolecge31Trouble Cause RemedyRegulatoroperatesfrequentlyIncorrectBandwidthPlace the Control Switch on the TEST position. Connect an AC voltmeter to theoutput test terminals. Adjust and check the desired bandwidth by rotating theBandwidth knob on the control panel.To check the bandwidth rheostat R28, disconnect the regulator internal orexternal supply to the control panel. Disconnect the multipin plug located in theupper-right-hand corner of the A1 circuit board after ensuring the control baclehas been removed from the bottom of the position-indicator housing.With a multi-purpose meter, check the resistance of each layer of R28. Eachshould be 10 ohms ± 2 percent. Also, check for shorting between the panelground and terminals of each layer. Replace the bandwidth rheostat if it isdefective. If normal, replace the component board.Time-delaysetting is toolow or thecircuits aremalfunctioningPlace the control in a balanced condition within the bandwidth. Start of the timedelay is initiated when the control is instantaneously placed out of the bandwidthby use of the level adjust potentiometer.The time between throwing the control out of the bandwidth and when the motorenergizes is the time delay. If this is drastically different ( ± 20 percent) fromthe calibrated setting, the time-delay circuit is malfunctioning. Calibrate this byadjusting R37. If it cannot be calibrated, remove the component board.Regulatorbuckswhen loadincreasesReversedpolarity in eitherthe currenttransformeror potentialtransformerReverse the current transformer leads in the control cabinet by disconnectingleads NN24 and NN23 (at the terminal board) and reversing the connections.Warning: Short-circuit the current transformer so the secondary will not becomeopen-circuited. (The current transformer is short-circuited automatically byremoving the control-cable plug from the bottom of the position-indicatorhousing.)RegulatoroperatesfrequentlyIncorrectBandwidthPlace the Control Switch on the TEST position. Connect an AC voltmeter to theoutput test terminals. Adjust and check the desired bandwidth by rotating theBandwidth knob on the control panel.To check the bandwidth rheostat R28, disconnect the regulator internal orexternal supply to the control panel. Disconnect the multipin plug located in theupper-right-hand corner of the A1 circuit board after ensuring the control baclehas been removed from the bottom of the position-indicator housing.With a multi-purpose meter, check the resistance of each layer of R28. Eachshould be 10 ohms ± 2 percent. Also, check for shorting between the panelground and terminals of each layer. Replace the bandwidth rheostat if it isdefective. If normal, replace the component board.Time-delaysetting is toolow or thecircuits aremalfunctioningPlace the control in a balanced condition within the bandwidth. Start of the timedelay is initiated when the control is instantaneously placed out of the bandwidthby use of the level adjust potentiometer.The time between throwing the control out of the bandwidth and when the motorenergizes is the time delay. If this is drastically different ( ± 20 percent) fromthe calibrated setting, the time-delay circuit is malfunctioning. Calibrate this byadjusting R37. If it cannot be calibrated, remove the component board.