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List 5Measuring Relay M170

Undervoltage / Phase Sequence Monitoring for AC Networks Characteristics

Voltage monitoring for 3-phase networks Two setting ranges for response and release value Adjustable relay delay from 0-10s For networks with or without neutral conductor With optional phase sequence monitoring and signalling

Description

T

he M170 is used for undervoltage and phase sequence monitoring in 3-phase networks.Potentiometer U

Mode of Operation

ON is used for adjusting relay response value with rising voltage in the range from 0.8 up to 1.2 of the rated voltage. At Potentiometer U The 3 phases of the AC network are monitored against the artificially formed star point or against the neutral conductor.The output relay only engages if all 3 phase voltages have exceeded the preset response value “U
HYS the release value of the relay is adjusted for falling voltage.A third Potentiometer allows the setting of a time delay from 0 up to 10s.Available is a 3-wire version
ON ”.The release value can for systems without neutral, and a 4-wire version for systems with neutral conductor. The measuring inputs be adjusted with the potentiometer “U
HYS ” in the range of 75 and 95% of the response voltage.Should 1,2 or all 3 phase voltages fall below the pre-set release

Models and Ordering Data

L3-N of the 4-wire version and L1-L3 of the 3-wire version are used to supply the internal circuits of the value “U
HYS ”, the output relay de-energises.Re-energization occurs only if all 3 phase voltages have exceeded the response value as described before.With the potentiometer “t”, the de-energising of the relay caused by undervoltage can be delayed. If all phase voltages exceed the response value during the delay period, the lapse of time is reset again and the relay remains energised. Effects of short undervoltage periods may be suppressed by this function.The phase sequence monitoring function requires in addition to the sufficient voltage the correct rotation direction of the 3 phases to energise the relay.The wrong phase sequence prevents the energising of the relay and is signalled by blinking of the yellow “PWR” LED.
2 CO ContactsContacts M170 .Further versions with additional phase sequence monitoring are available.Two LEDs in the front of the relay provide a visual display of the mains voltage applied and show the output relay energised.The relay works on the closed circuit principle. Type M170 / 400 V
AC Order-No. 4
- wire 072 00107072 00297072 00292072 00298 4
- wire + Phase Sequence3
- wire 3
- wire + Phase Sequence
60Hz version on request

Automation Control Components