| Earth Resistance Ranges | 0.001 – 1.999Ω |
| 0.01 – 19.99Ω |
| 0.1 – 199.9Ω |
| 1 - 1999Ω |
| Accuracy (20°C) | ±2% of reading ±2 digits |
| Temperature Effect | ±0.1% per °C |
| Working Temperature Range | -15°C to +50°C |
| Storage Temperature Range | -30°C to +7C°C |
| Humidity | 95% A.H. combined with cyclic temperature changes of25°C to 40°C (BS2011: Part2.1, Db: 1977, IEC68-2-30: Test Db: 1969) |
| Test Frequency | 128Hz reversing d.c. |
| Interference | Steady interference voltages at d.c., 50 or 60Hz will be rejected. The effect of transient noise is minimised by a switched filter. |
Maximum interference:-
2Ω range low current ± 5V peak
2Ω range normal current ± 10V peak
all other ranges and currents ± 20V peak |
| Filter Time Constant | Normal (filter switch 'OUT') 1 second |
| Long (filter switch 'IN') 10 seconds |
| Test Current | High 40mA |
| Normal 10mA |
| Low 5mA |
| Maximum Current Spike Resistance | The maximum permissible resistance of the current loop depends on the test current selected:-
High current: 800Ω
Normal current: 3.5kΩ
Low current: 7.5kΩ |
| Maximum Potential Spike Resistance | The input impedance between the potential terminals is - 2MΩ. A maximum potential loop resistance of·10kΩ will give an additional error of 0,5%. |
| Output Voltage | 50V maximum from the Cl, C2 terminals |
| Display | 3% digit l.c.d. maximum reading 1999 |