The GM420 series loop monitor is designed to monitor the resistance of PE conductor connections in AC systems and in de-energised systems. The extraneous voltage Uf between the terminals E and KE must not exceed AC 12 V. The ohmic resistance of the conductor loop and the AC extraneous voltage Uf, if existing, will be indicated on the display. The currently measured value is continuously indicated on the LC display. If the measured resistance value increases above the set response value, the alarm will be activated and stored. Adjustable time delays allow installation-specific requirements to be considered.
Features
Loop monitoring of the PE conductor in AC systems
Measuring circuit providing a high resistance against extraneous voltages and indication of extraneous voltages
Adjustable start-up delay, response delay and delay on release
Adjustable switching hysteresis
Digital measured value display via multi-functional LC display
Preset function (automatic setting of basic parameters)
LEDs: Power On, Alarm 1, Alarm 2
Measured value memory for operating value
Continuous 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
Loop monitoring of motors
Loop monitoring of PE conductor connections for wire interruptions in electrical installations
Monitoring of earthing systems