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The CME420 series current relays monitor undercurrent and overcurrent in AC systems as well as the current between two threshold values (window discriminator function). The currents are measured as r.m.s. values (AC). The currently measured value is continuously shown on the LC display. The measured value required to trigger the alarm relay is stored. Due to adjustable delay times, installation-specific characteristics, such as device-specific making currents, short-time current changes etc. can be considered. Current measurement is possible either directly or indirectly via standard current transformers (x/5 A). External supply voltage is required.


  • Undercurrent and overcurrent monitoring in AC systems 0.1…16 A
  • Indirect current monitoring with standard current transformers x/5 A
  • Transformation ratio n allows adaptation to all standard current transformers x/5 A
  • Different monitoring functions selectable < I, > I or < I/> I
  • Start-up delay, response delay, delay on release
  • Adjustable switching hysteresis
  • r.m.s. value measurement (AC)
  • Digital measured value display via multi-functional LC display
  • LEDs: Power On, Alarm 1, Alarm 2
  • Measured value memory for operating value
  • Continuous self monitoring
  • Internal test/reset button
  • Two separate alarm relays (one changeover contact each)
  • N/C or N/O operation and fault memory behaviour selectable
  • Password protection for device setting
  • Sealable transparent cover
  • Two-module enclosure (36 mm)
  • Push-wire terminal (two terminals per connection)
  • RoHS compliant


  • Current consumption of motors, such as pumps, elevators, cranes
  • Monitoring of lighting circuits, heating circuits, charging stations
  • Monitoring of emergency lighting
  • Monitoring of screw conveyors, e.g. in sewage plants
  • Dust removal in wood working

Downloads for LINETRAXX® CME420

CE Declarations of Conformity CME42x 87.6 KB 2022/08/12 06:17:2312.08.2022 06:17:23
Manuals CME420 1.5 MB EN2020/09/11 10:14:1211.09.2020 10:14:12D00034
Datasheets CME420 301.5 KB EN2019/05/13 10:31:3513.05.2019 10:31:35D00034
Datasheets XM420 interface options 223.5 KB EN2019/05/13 10:31:3613.05.2019 10:31:36D00051
Technical Information Changed variants of relays from goldplated to silver-plated contacts 166.3 KB EN2022/06/27 09:03:0827.06.2022 09:03:08

Optional Accessories for LINETRAXX® CME420

TypeArt. No.
Mounting clip for screw fixing (1 piece per device)B98060008

LINETRAXX® CME420 Variants

TypeSupply voltage US*MeasurementDisplay rangeResponse valueArt. No.**
CME420-D-1DC 9.6…94 V/
AC 16…72 V,
42…460 Hz
via current transformer x/5A
0.1…16 A/
5…999 A
0.1…16 A x nB73060001
CME420-D-2DC 70…300 V/
AC 70…300 V,
42…460 Hz
via current transformer x/5A
0.1…16 A/
5…999 A
0.1…16 A x nB73060002

* absolute values
**(B7… = push-wire terminal / B9… = screw-type terminal)