SP Set Point of the OVER/UNDER VOLTAGE control, from 2% to 20% of VN (VN = mains phasephase rated voltage) adjustable by screwdriver. If in one phase V<0,6VN, there is the triggering for phase failure. ASYM Set Point of the ASYMMETRY control VM-Vm from 5% to 20% of VN, adjustable by screwdriver. VN Choice of the value of VN (mains rated voltage) among the values 380V, 400V, 415V (for the MODEL A), adjustment by screwdriver (the indicator must be placed in the center of each of the 3 sectors). T Timer 0,2÷30 sec. adjustable by screwdriver, it is activated by the overcoming of SP or of ASYM and it delays the triggering of relay. During T the leds SP and ASYM flash. VISUALIZATIONS ON GREEN LED: supply on. SP RED LED: in case of OVERVOLTAGE it flashes, in case of UNDERVOLTAGE it is steady lighted. ASYM RED LED: in case of set point overcoming, it is steady lighted. L123 YELLOW LED: it is lighted if the phase sequence is L1, L2, L3 at pins 5, 3, 1, it flashes if the phase sequence is different. RESET: it is automatic when the triggering value decreases by 12,5% for SP or when the ASYMMETRY decreases by 12,5%. MODE OF OPERATION With the regulations on the front it is possible to fix the value of VN, mains rated voltage, and it is possible to fix the triggering values for OVER/UNDER VOLTAGE and for ASYMMETRY. The Tab. A shows the SET POINTS and the matched leds. REMARK: if the phase sequence is not L1, L2, L3, the relay is immediately in alarm. POSITIVE SAFETY The relay is normally ON and it goes OFF when it is in alarm. INSTALLATION See the fig. 2. (Wiring to an electrical board with a differential relay and a sectionalizing switch). The length of every wiring must be less than 30m. INPUT: 5-3-1 100Vac or 380Vac/415Vac. It is requested that the pins 5-3-1 correspond to the phases L1, L2, L3 to ensure that the relay is not already in alarm once turned on. The YELLOW LED L123 must be ON. OUTPUT: : 1 output relay with two changeover contacts (5A-230Vac) resistive load. - I=3A,V=250VAC,cosϕ=0,7 : 100.000 operations - I=0,6A,V=250VAC,cosϕ=1 : 1.000.000 operations - I=0A : 20.000.000 operations (Mechanical Life) 11-10 / 14-15 NC Device not supplied 11-12 / 14-13 NO or in alarm Insulation between input and contact: VDE 0110 - IGR C/660 Insulation of the contact: VDE 0110 - IGR C/250 SUPPLY (pin 3-5) 2VA - 50÷60 Hz. Self-supplied by the voltage to be monitored. RANGES 100 Vac, 380 / 400 / 415 Vac. CASE • Self-extinguishing ABS. DIMENSIONS: 45x70x110 mm for DIN rail. Accessories available on request: E 405B transparent protection fitted for tight closure. WORKING TEMPERATURE: 0÷70°C WEIGHT: 0,300 kg COLOUR: grey

FUNCTION The V3-20 must be programmed so that the VN voltage (phase-phase voltage of the mains to be protected) is selected on its front among the values 380V, 400V, 415V. There are 2 programmable controls: - The OVER/UNDER VOLTAGE control. - The ASYMMETRY control. With the OVER/UNDER VOLTAGE control it is checked if at least one phase-phase voltage deviates from the value of VN more than what is set with the SP SET POINT (from ±0% to ±20% of VN). Example: with VN=400V (3%→12V, 10%→40V, 20%→80V), If SP=10%→400V+40V=440V and 400V-40V=360V are set. If at least one phase-phase voltage overcomes 440V, the triggering for OVERVOLTAGE is obtained. If at least one phase-phase voltage goes under 360V, the triggering for UNDERVOLTAGE is obtained. The reset is obtained for values where ∆V=40V is reduced by 12% that is ∆V!35V, thus 435V and 365V. In the ASYMMETRY control the ASYM set point goes from 5% VN to 20% VN. 3 phase-phase voltages are measured, the greatest (VM) and the lowest (Vm) are chosen, furthermore it is checked if VM-Vm is greater than the value set with the indicator. Example: with VN=400V (5%→20V, 10%→40V, 20%→80V), if ASIM=10% is set and VM-Vm > 40V, the relay is in alarm. There is the reset for the value obtained with 40V reduced by 12%, that is 35V, thus 35V is the reset value. There are 2 not-programmable controls: PHASE SEQUENCE and PHASE FAILURE (See Tab. A). PHASE SEQUENCE: if the phases L1, L2, L3 are present at pins 5-3-1, the yellow led is ON and the inside relay is ON. If the phase sequence is different, the yellow led “flashes” and the inside relay is OFF. PHASE FAILURE: if for one of the 3 phases V<0,6VN occurs (Ex. VN=400V→V<240V), the leds SP and ASYM flash and the inside relay goes OFF. The triggering time of these 2 controls is < 2 seconds. The device is self-supplied by the voltages present at pins 5 and 3, if the decrease concerns these voltages the relay can go OFF. USE Monitoring of a three-phase mains.

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