General Information
HDJD-470 Earth resistance tester is specially designed and manufactured for ground resistance, The testing current reaches 20mA. The digital and micro-processing technology, precision 3-wire method and simple 2-wire method are used to measure ground resistance, importing FFT (Fast Fourier Transform) technology, which is widely used in electric power, telecommunications, meteorology, oil field, construction, lightning protection, industrial electrical equipment and other earth resistance, earth voltage measurement.
Technical parameter
| Function | Grounding resistance, low resistance test, grounding voltage test. |
| Power | DC 7.4V 1.8Ah rechargeable Li-battery, battery full charge time 8h. |
| Back light | Controllable white screen backlight, suitable for use in dark field. |
| Testing method | Precision three wire method and simple two wire method to test grounding resistance |
| Measure method | Earth Resistance: rated current change-pole method, |
| Earth Voltage: average rectification(between P(S)-ES) | |
| Range | 23 wire method for measuring ground resistance (R)：0.00Ω～3000Ω |
| Grounding voltage：AC 1～600.0V(50Hz/60Hz) | |
| Max. resolution | 0.01Ω; 1V |
| Accuracy | Grounding Resistance: +2% rdg+5dgt Note: 1. Auxiliary Grounding Resistance 100_+5%, Ground Voltage < 5V 2. Additional error (<5%rdg+5dgt) at 5V interference voltage |
| Grounding voltage： ±2%rdg±3dgt | |
| Short circuit test current | AC 20mA max |
| Open circuit test voltage | AC 40V max |
| LCD | 6” LCD display, white screen backlight |
| LCD size | 128mm×75mm |
| LCD display size | 124mm×67mm |
| Testing indication | LED flashing indication in measurement.LCD count down.Progress bar chart indication |
| Size | Host machine：Length Width Height 320mm×275mm×145mm |
| Outer size：Length Width Height 400mm×245mm×335mm | |
| Standard test wire | Total 3pcs：red wire 20m，yellow wire 10m，green wire 5m, each 1pcs |
| Simple test wire | Total 2pcs：red wire 1.6m，black wire 1.6m each 1pcs |
| Auxiliary grounding rod | 2 pcs：φ10mm×150mm |
| Test time | Ground voltage: approx 2times/sec； ground resistance：approx 7times/sec； |
| Test times | 5000times above ( short circuit test, test 1 time,Stop for 30 seconds and retest. ) |
| Circuit voltage | AC 600V |
| Communication port | With RS232 interface, storage data can be uploaded to the computer and saved to print. |
| communication wire | RS232 communication wire 1pcs, length 1.5m |
| Data save | 100 SET，“MEM”Storage instructions，display “FULL”Indicates that the storage is full. |
| Data read | the “READ” symbol indicates look up data |
| Interface test | Recognize interference signal automatically, “NOISE” icon display when interference voltage exceed 5V |
| Alarm function | When measuring value exceeds alarm setting value, there is “Toot-toot-toot” alarm hint |
| Battery voltage | When low battery, battery voltage low icon will display, reminding to charging battery. |
| Working current | Standby: about 25mA (Backlight shut off)； backlight：25mA Max(only backlight consumption)； Measurement: about 150mA (Backlight shut off) |
| Weight | Host machine：2.645kg(with battery) |
| Total weight：5.95kg(with package) | |
| Overload protection | Measure ground resistance ：C(H)-E、P(S)-ES between each port AC 280V/3sec |
| Insulation resistance | 20MΩ above(between circuit and shell 500V) |
| Withstand voltage | AC 3700V/rms(between circuit and shell) |
| Comply standard | IEC61010-1(CAT Ⅲ 300V、CAT IV 150V、pollution class2)； IEC61010-031；IEC61557-1(ground resistance)； IEC61557-5(soil resistivity)；JJG 366-2004(ground resistance meter)。 |
