Continuous Earth Grid / PIT Monitoring System - CEMS0121-PIT
Introduction
The traditional method of measuring Earth pit resistance by wenner method by disconnecting the earth pit connection from the earth grid and measuring the individual pit resistance by a meter can be replaced with the earth pit resistance and monitoring system, CEMS0121-PIT.
With CEMS0121-PIT, there is saving in time and efforts in searching for most suitable places to position the probes for 3-point or 4-point measurement, especially for highly resistive soils. The added benefits of continuous monitoring and relay output for unhealthy condition (open or high resistance) can be also used for process application.
CEMS0121-PIT provides an advanced earth pit resistance measurement and monitoring system.
It is provided with display for indicating measured resistance value, red indication lamp for open earth loop resistance value and green indication lamp for healthy condition of earth loop resistance value i.e. less than the set value (typically 10 ohms).
Also, the output relay is provided for alarm/ annunciation CEMS0121-PIT is provided with flame proof enclosure for installation in hazardous areas with flammable atmosphere.
Principle of Operation
CEMS0121-PIT is connected between two earth pits or in series connection with one earth pit and grid connection of the earth pit.
CEMS0121-PIT applies voltage across the two earth pits/ earth pit to grid connection and the current flow is measured. The resistance is internally calculated from the applied voltage and current flowing through the earth pits.
LED display unit on CEMS0121-PIT reads the measured value of resistance. The device continuously measures resistance and increase in resistance beyond the set value, (typically 10 ohms) would initiate the relay output which can be used for interlocking, alarm or annunciation.