SCR ELEKTRONIKS have developed an equipment namely Earth Contact Resistance Tester to test the appliance. To ensure the safety of operator it is essential that the Earth path (connection) should offer minimum impedance to by pass short circuit Current to Earth. This is ensured by measuring Resistance of the Earth path by passing heavy Current say 25 A. The Earth Contact Resistance Tester essentially comprises of a Variable Current source with digital Ammeter to measure the Current supplied. The Voltage drop across the Earth path is measured with a digital Voltmeter. Optionally for a particular Current (25 A) the meter can be calibrated in terms of Resistance. A timer is provided to switch off the Current after the Set Time.
AC Variable Current Source 0 to 30A AC @10V.
Digital Ammeter 0 to 30.0A True RMS – 1 No.
Digital mV /Ohm Meter with following range : a) For mV – 0 to 200mV/2V range. b) For Resistance 0 to 1.999 Ohms.
The resistance will calibrated at 25A AC current.
Output – On binding post type terminals 4 Wire measurement system.
Two terminal for current & Two terminal for measurement of mV drop. a) Mains ON/OFF switch b) mV/Resistanace range switch Range.
Output ON/OFF with Push button & Relay.
Built in Extruded Aluminium section with duly powder coated M.S. covers Table top Model.
Input supply 230 V +/ - 10% AC 50HZ.
Current source : 0 to 30 A max.
Test Voltage : 12 V max.
Digital Display 3 1/2 digit for all measurable parameters (Ammeter, Voltmeter and Resistance - 0.001 Resolution for 1.999 Ohms range) at 25 A current.
Voltage measurement: Two ranges namely 2 V, 20 V.
Current Measurement: 0 to 30 Amps.
Resistance Measurement: At 25 Amps. 0 to 1.999 Ohms.
Separate Voltage and Current terminals.
The test bench can be customized as per the constant current value that is passed thrugh the earthing circuit, but usually the tester is procured with 30 A capacity
The tester is used to measure the voltage drop of the earthing circuit at a constant current - thus assessing how well the product eart is 'bounded' to the system earthing