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Single-phase Voltage Relay
with indication

NL-19 - single-phase voltage relay


The relays NL-19 are the static relays of a direct and alternating current (DC: =110, 220 V; AC: ~110, 220 V; 50, 60 Hz), without an operative power supply, but with digital indication of value of the controllable parametre and with programmed discrete installation of actuating settings of input influencing value.

Depending on the change of input acting value the relays NL-19 are divided into the relays of maximum and minimum voltage.

Rated AC/DC supply voltage: 110 V, 220 V.
Supply voltage range: =75...265 V, ~75...265 V.
The basic error of measurement: 5%.
Voltage discreteness of the settings: 1 V.
The time discreteness of the settings: 1 s.

Basic parameters NL-19
Setting the actuating voltage (programmable) upper threshold UU.T.
lower threshold UL.T.
Hysteresis (programmable) of upper threshold:
ΔUU.T. - 2% of UU.T.
of lower threshold:
ΔUL.T. - 1...15% UL.T.
Time delay (output relay actuating),
- turning on ton:
- turning off toff:

0…300 s
not more than 0,1 s

Operating conditions:

  • for the version of U3 - from minus 40 to 55 °C;
  • for the version of T3 - from minus 10 to 55 °C.

The relay design provides installation by projecting mounting with front connection of wires under screw on a rail DIN 35.
Relay circuit of NL-19 provides galvanic isolation of control circuits (terminals "3", "4", "5") with supply circuit (terminals "1", "2").

Functional diagrams of operation

  • Urated – rated value of monitored voltage;
  • UMAX – upper threshold of monitored voltage;
  • UMIN – lower threshold of monitored voltage;
  • ΔUMAX – hysteresis of the maximum voltage (ΔU return hysteresis);
  • ΔUMIN – hysteresis of the minimum voltage (ΔU return hysteresis);
  • Р – relay actuating;
  • Δton – turning on delay of output relay;
  • toff – turning off delay of output relay;
  • С – indication of a light-emitting diode.

NL-19 - functional diagram