MRU-21 –USER MANUAL
CONTENTS
1Safety ................................................................................................................4
2Settings.............................................................................................................5
3Measurements..................................................................................................6
3.1 Earth resistance measurement with 3-pole method (RE3P).....................................6
3.2 Earth resistance measurement with 2-pole method (RE2P)...................................10
3.3 Measurement of resistance of earth connection and equipotential bonding (RCONT)....12
3.4 Calibration of test leads .........................................................................................14
3.4.1 Turning AUTOZERO on...............................................................................................14
3.4.2 Turning AUTOZERO off...............................................................................................15
4Memory ...........................................................................................................16
4.1 Storing the measurement result data in the memory .............................................16
4.2 Viewing memory data............................................................................................. 18
4.3 Deleting memory data............................................................................................19
4.3.1 Deleting bank data.......................................................................................................19
4.3.2 Deleting the whole memory..........................................................................................20
4.4 Communication with a computer............................................................................ 21
4.4.1 Computer connection accessories ...............................................................................21
4.4.2 Data transmission........................................................................................................21
5Meter power supply .......................................................................................22
5.1 Monitoring of the power supply voltage.................................................................. 22
5.2 Replacement of batteries....................................................................................... 22
6Cleaning and maintenance ...........................................................................25
7Storage............................................................................................................25
8Dismantling and utilization...........................................................................25
9Technical specifications ...............................................................................26
9.1 Basic data ..............................................................................................................26
9.2 Additional information ............................................................................................ 28
9.2.1 REmeasurement..........................................................................................................28
9.2.2 RCONT measurement.....................................................................................................29
10 Accessories....................................................................................................30
10.1 Standard accessories ............................................................................................ 30
10.2 Optional accessories.............................................................................................. 30
11 Manufacturer ..................................................................................................31
12 Laboratory services.......................................................................................32
