LINETRAXX® CMD420/CMD421

The CMD420/421 current monitoring devices monitor AC currents using three measuring inputs for overcurrent, undercurrent or undercurrent and overcurrent (window discriminator function). The currents are measured as r.m.s. values (AC). The currently measured values are continuously shown on the LC display. The respective measuring channel can be selected using the Arrow up or Arrow down button. The measured values causing the alarm relay to switch are stored. Due to adjustable delay times, installation-specific characteristics, such as devicespecific making currents, short-time current changes etc. can be considered.

For the measurement three standard current transformers are to be connected to the respective CMD420/421. The transformation ratio "n" of the current transformers (n = x/1A resp. n = x/5A) can be set up to a factor of n = 2000.

Then the actual current of the installation can be calculated by multiplying the measured current by factor "n" and indicated on the display. The currents can derive from a 3-phase system or from three different single-phase systems.

The CMD420/421 series requires external supply voltage

Questions? Contact us!

The CMD420/421 current monitoring devices monitor AC currents using three measuring inputs for overcurrent, undercurrent or undercurrent and overcurrent (window discriminator function). The currents are measured as r.m.s. values (AC). The currently measured values are continuously shown on the LC display. The respective measuring channel can be selected using the Arrow up or Arrow down button. The measured values causing the alarm relay to switch are stored. Due to adjustable delay times, installation-specific characteristics, such as devicespecific making currents, short-time current changes etc. can be considered.

For the measurement three standard current transformers are to be connected to the respective CMD420/421. The transformation ratio "n" of the current transformers (n = x/1A resp. n = x/5A) can be set up to a factor of n = 2000.

Then the actual current of the installation can be calculated by multiplying the measured current by factor "n" and indicated on the display. The currents can derive from a 3-phase system or from three different single-phase systems.

The CMD420/421 series requires external supply voltage

Questions? Contact us!

Features

Undercurrent and overcurrent monitoring in AC systems with prealarm and main alarm or current monitoring with window discriminator function
Current monitoring using current transformers, suitable for standard transformers x/1 A, x/5 A (depending on the device type)
Transformation ratio n allows adaptation to all standard current transformers x/1 A, x/5 A
Start-up delay, response delay and 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

Fault memory for the operating value
Cyclical self monitoring
Internal test/reset button
Two separate alarm relays with 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

Applications

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
70 % agreement in accordance with EEG 2012 for PV inverters