SEW 1120 ER 3 Wire (Digital) Earth Resistance Testers
SEW 1120 ER is a professional instrument suitable for testing single earth electrodes such as lightning conductors and other small earthing systems. The unit can also measure the resistance of conductors such as continuity and conduit coupling joints.
The instrument is powered by 8 x 1.5 volt manganese alkaline AA batteries. Calibration of the instrument is performed with the included test leads. When using all three test leads in the three-terminal method, accuracy is assured for most common applications. Alternatively, two-terminal measurements, though generally less accurate than three-terminal measurements, are also possible by shorting the P and C terminals or by using the simplified measurement probe.
The test frequency of 820Hz avoids stray currents at power frequencies and their harmonics. Additionally, the 1120 ER utilizes a built-in filter to reject unwanted signals. The batteries are constantly being checked while in use. The rugged case is ideal for outdoor work. Earth electrode testing, which is an important part of electrical installation and maintenance procedures, is made easy with the 1120 ER. It can be used by electrical contractors or maintenance engineers to check the effectiveness of their earth electrode systems.
Features
- Waterproof: IP54
- Capable of measuring earth resistance and earth voltage
- 2mA measuring current permits the testing of earth resistance without tripping earth leakage current breakers in the circuit under test
- The test leads are supplied as standard accessories for simplified two-wire measuring system
- 0Ω adjustment
- Battery operated
- Data hold function
- Low battery indication
Specifications
| Measuring Ranges | Earth Resistance: 0-20Ω / 0-200Ω / 0-2000Ω Earth Voltage: 0-200 VAC (40-500Hz) |
| Accuracy | Earth resistance ±(2%rdg+2dgt) or ±0.1Ω, which is greater Earth voltage ±(1%rdg+2dgt) |
| Earth Resistance Resolution | 0-20Ω : 0.01Ω 0-200Ω : 0.1Ω 0-2000Ω : 1Ω |
| Measuring System | Earth resistance by constant current inverter 820 Hz, 2mA approx. |
| Display | 3½ digit (2000 counts) |
| 0Ω Adjustment | √ |
| Open Circuit Indication | LED will be unlit |
| Low Battery Indication |  symbol appears on the display |
| Data Hold Indication |  symbol appears on the display |
| Over Range Indication | “1”(MSD) |
| Dimensions | 175(L) × 85(W) × 75(D)mm |
| Weight (battery included) | Approx. 600g |
| Power Source | 1.5V (AA) × 8 |
| Safety Standards | IEC/EN 61010-1 CAT III 200V IEC 61557-1 IEC 61557-5 EN 61326-1 |
| Datasheet | 1120ER |
