Monitoring Relays 3-Phase Max. and Min. Current Control Type H 475 * 3-phased current metering relay * Measures on current with 3-phased current metering transformers, type A74-.. ... * Measures if all 3-phase currents are within set limits * Upper and lower limits separately adjustable * Output: 10 A SPDT relay * For mounting on DIN-rail in accordance with DIN/EN 50 022 * H4-housing * LED-indication for power supply and output ON * AC power supply 2-phases Product Description Ordering Key 3-phase current metering relay with separate setting of upper and lower current level. For DIN-rail mounting. Often used where a certain applica- Housing Type Output Power supply tion such as a large mixer has to be kept within a set current value in order not to overload the system. H 475 156 230 Type Selection Plug Output Supply: 115 VAC Supply: 230 VAC Supply: 400 VAC Screw terminals SPDT H 475 156 115 H 475 156 230 H 475 156 400 Input Specifications Output Specifications Input from current transformers Terminal 5 Terminal 6 Terminal 7 Terminal 8 Input voltage Output Rated insulation voltage A74-.. ... red, phase L1 white, phase L2 yellow, phase L3 black 0.4-4 Vp Supply Specifications Power supply AC types Rated operational voltage Through term. 22 & 24 115 230 400 Voltage interruption Dielectric voltage Rated impulse withstand volt. Rated operational power Overvoltage cat. III (IEC 60664) (IEC 60038) 115 VAC 15%, 45 to 65 Hz 230 VAC 15%, 45 to 65 Hz 400 VAC 15%, 45 to 65 Hz 40 ms 2 kVAC (rms) (supply/elect.) 4 kV (1.2/50 s) (line/neutral) (line/line), no direct connection to electronics 2.5 VA Specifications are subject to change without notice (04.11.05) Contact ratings (AgCdO) Resistive loads AC 1 DC 1 or Small inductive loads AC 15 DC 13 Mechanical life Electrical life AC 1 SPDT relay 250 VAC (rms) (cont./elect.) (micro gap) 10 A/250 VAC (2500 VA) 1 A/250 VDC (250 W) 10 A/25 VDC (250 W) 2.5 A/230 VAC 5 A/24 VDC 30 x 106 operations 2.5 x 105 operations (at max. load) 7200 operations/h Operating frequency Dielectric strength Dielectric voltage 2 kVAC (rms) (cont./elect.) Rated impulse withstand volt. 4 kV (1.2/50 s) (cont./elect.) (IEC 60664) 1 H 475 General Specifications = 0.2 s, worst case reaction time may be up to 5 x Reaction time Indication for Power supply ON Output ON Environment Degree of protection Pollution degree Operating temperature Storage temperature Weight LED, green LED, red (IEC 60947-1) IP 20 B/front IP40 D (IEC 60529) 3 (IEC 60664) -20 to +50C (-4 to +122F) -50 to +85C (-58 to +185F) 300 g CE Marking Yes Range Setting Mode of Operation The relay requiring 2-phased power supply is used with one of the 3-phased current metering transformers, types A 74-10 5, A 74-10 20, A 7411 100, A 74-11 500. When the supply voltage is applied the relay operates, provided the current flowing in all 3phase cables exceeds the minimum current of the transformers and phase cables must be drawn through the transformer from the same side. When the power supply is applied the relay operates when all 3-phase currents are within the set levels, and releases when one or more phase-phase currents exceed the upper set level or drop below the set level. The relay operates again when all 3-phase currents are within the set levels. Hysteresis on operate is approx. 2%. The phase sequence through the current metering transformer is arbitrary. Wiring Diagram Measuring range 3-phased current metering transformers measure in the following 4 ranges: A 74-10 5 = 0.5- 5 A A 74-10 20 = 2 - 20 A A 74-11 100 = 10 - 100 A A 74-11 500 = 50 - 500 A Range setting Left potentiometer: Lower limit. From 8 to 98% of nominal max. value for the current metering transformer employed. Right potentiometer: Upper limit. From 10 to 100% of nominal max. value for the current transformer employed. If the lower limit is set above the upper limit, the output relay releases and cannot be activated before the lower limit is set lower than the upper limit. Term. 5: Red core Term. 6: White core Term. 7: Yellow core Term. 8: Black core Hysteresis Max. limit: - 2% Min. limit: + 2% Power supply H 475 PE = term 8 Operation Diagram Upper limit Hysteresis Lower limit Relay ON 2 Hysteresis L1, L2, L3 Specifications are subject to change without notice (04.11.05)