AC Current

AC Current


DIN rail mounting protection relays for use in single and three phase systems. Available in 55mm x 112mm or 100 x 112mm DIN rail cases.


For over protection, under protection and combined under & over protection available in AC current AC voltage & frequency versions. Millivolt trip, DC voltage trip, Reverse Power, Phase sequence & Phase balance relays also available in our extensive range of protection relays.

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Selection Guide

M200-A1USingle phase under current
M200-A1OSingle phase over current
M200-A1CSingle phase combined current
M200-A3U3 phase under current
M200-A3O3 phase over current

Typical Applications

The M200 AC current relays provide current monitoring and protection in both single and 3 phase systems. Used in applications such as motor protection, load detection and generator control. Under, over and combined under/over units are available. The relay operates when the adjustable trip point is reached. An externally adjustable time delay is provided to prevent nuisance tripping. As is common with all the M200 relays, on over relays the unit energises when the input signal exceeds the trip point. On under units the relay de-energises when the input signal goes beyond the trip point. A red LED indicates the condition of the power supply.

Technical Specifications

Rated value In1A or 5A from C.T. 0.2 to 10 Amp direct connected
Burden<0.5VA per phase
Overload2 x In continuous 10 x In for 3 seconds
Range OverAdjustable 40% to 120% In
Range UnderAdjustable 0% to 80% In
RepeatabilityBetter than 0.5% of span
DifferentialFixed 5%
Time DelayAdjustable 200mS to 10 seconds
AC Voltage115 / 230 / 400V
DC Voltage24 volt(±20% / galvanically isolated)<3 watt
Single UnitsApprox 0.4kg 55mm case
Combined UnitsApprox 0.6kg 100mm case

Ordering Information

Product CodeInputFreqAux


1Adjustable time delay max 30 seconds
2AC Auxiliary in range 57.7 to 480 volts
3Calibration at nominal Hz
4Calibration at temperature other than 23ºC.

Connection Diagrams

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