Phase-failure relays

Purpose:Phase-failure relays monitor the state of a three-phase network and protect the load against impermissible voltage deviations in one or more phases (phase imbalance or asymmetry), a change in phase sequence, and the loss of one or more phases.

ЕЛ-11М

Distinctive features:

Microprocessor control with digital signal processing. No adjustment required.
Monitoring of phase loss and phase sequence.
Phase imbalance monitoring.
Umin monitoring.
Adjustable switch-off delay when the voltage falls below Umin.
Hysteresis on re-closing.
Output status shown on a bi-colour LED.
Powered from the monitored network.
Versions for nominal phase voltages of 220 V and 127 V.
Galvanically isolated normally closed and normally open contacts.
Switching life at least 3×10⁷.
DIN-rail mounting, 35 mm case.

Technical specifications:

Power consumption, max: 4 W
Mains frequency, (48 – 62) Hz
Operating voltage, 380/220 V
Maximum switched current for a resistive load — 8 A
Maximum switched AC voltage — 250 V
Overall dimensions, 86×35×60 mm
Weight, max, 200 g.
Operating temperature range (-25 – +55) °C
Storage temperature, (-40 – +70) °C
Timing accuracy: better than ±5%
Climatic category УХЛ
Mounting method and method of connecting external leads:
- for DIN-rail mounting;
- supply conductors connected via terminal blocks.

Datasheet for the ЕЛ11М phase-failure relay

ЕЛ-11М2

Distinctive features:

Microprocessor control with digital signal processing.
No adjustment required.
Phase loss monitoring.
Phase sequence monitoring.
Phase imbalance monitoring.
Umin and Umax monitoring
Neutral conductor break monitoring.
Switch-off delay when the voltage falls below Umin or rises above Umax.
Hysteresis (reset ratio) on re-closing.
Input and output status shown on a bi-colour LED.
Powered from the monitored network.
Two groups of isolated changeover contacts
DIN-rail mounting, narrow case (35 mm).
Voltage setpoints, hysteresis and operating time can all be changed in software.

Technical specifications:

Monitored circuit connection: three phases with neutral.
Nominal operating voltage 380/220 V
Mains frequency, 48 - 62 Hz
Upper pickup threshold — 264 V
Lower pickup threshold — 165 V
Hysteresis, 10 V
Pickup delay on Umin, and on loss of a phase — 1 s
Pickup delay on Umax, and on complete loss of voltage on all three phases — 0.15 s
Pickup delay on a change of phase sequence — 0.1 s
Active power consumption, max: 3 W
Insulation voltage input-to-contact and contact-to-contact — 1000 V
Overall dimensions, 90×65×35 mm
Weight, max, 200 g
Operating temperature range (-25 – +55) °C
Voltage pickup accuracy better than ±3%
Delay timing accuracy: better than ±5%
Climatic category УХЛ
Protection rating IP20
Mounting method and method of connecting external leads:
for DIN-rail mounting; supply conductors connected via terminal blocks
The terminals accept external conductors of at least 1.5 mm².

Datasheet for the ЕЛ11М2 phase-failure relay