Combined Under / Over Voltage & Under / Over Frequency Relay   Application :   The Rishabh combined Voltage & frequency Protectors give continuous surveillance of the monitored circuit. The product offers user adjustable trip point(set point) for voltage and frequency, plus adjustable time delay settings. The set point adjustment range is 25%, operating between 75% and 100% of the nominal supply for under voltage, and between 100% and 125% for over voltage. The frequency set point adjustment range is centered around the nominal 50Hz, 60Hz or 400Hz system frequency. The time delay setting adjustment range is typically 0 to 10 seconds, although longer delays are available.   As soon as the monitored signal moves outside the set point limit, the time delay is activated, after which a trip will occur. The time delay prevent the relay from tripping for a predetermined period to prevent nuisance tripping. The product also feature an internal differential (hysteresis) setting of 1% to reduce nuisance tripping if the measured signal is noisy or unstable. The product is available for single phase systems only, and draws its operating power from measuring input.       Features :   • Adjustable set point   • Adjustable time delay   • Internal differential   • LED trip indication   • 2 pole relay contacts         Specifications :   Nominal Voltage 120 & 240V a.c. Voltage Range Over voltage100 to 125% Under voltage 75 to 100% Differential Fixed internally 1 to 15%(Specify) Time Delay Adjustable between 1 and 30 seconds Frequency Ranges 40-60Hz (50Hz) or 50-70Hz (60Hz) or 400Hz Differential Fixed internally 0.1 to 3Hz (specify) Time Delay Adjustable between 1 and 30 seconds Set Point Repeatability Better than 0.5% Voltage Withstand 12 x continuously 1.5 x for 10 second x 10 operations to BS6253 Output Relay : Type D.P. Changeover Rating A.C 240V,5A non-inductive   D.C View chart Operations 0.2 million at the above loads Reset Automatic       LEDS: Indicate condition of relay, i.e illuminated when relays de-energise. Relays will be energized when the voltage/frequency is within the set point. Relays de-energise on trip point when the voltage/frequency goes over or under the set point excluding the time delay period.         - Protector Trip Relays   - A.C. Current Relay   - A.C. Voltage Relay with adjustable differential   - A.C. Voltage Relay with adjustable time delay   - Frequency Relay   - Combined Under / Over Voltage & Under / Over Frequency Relay   - Phase Sequence & Phase Failure Relay   - Phase Balance Relay   - Reverse Power (Current) Relay   - Synchro-Check Relay(Paralleling)   - D.C. Voltage Relay   - Thermistor Trip Relay   - Hot Spot 3 Relay   - Hot Spot 6 Relay   - Millivolt / Thermocouple Relay   - Transducer Trip   - Speed Sensing Trip Relay