1. Introduction
The ETCR3200C is a versatile digital ground resistance meter designed for precise measurement of earth resistance, soil resistivity, earth voltage, AC voltage, and grounding lead leakage current. It supports multiple measurement methods including 2-wire, 3-wire, 4-wire, selection, and double clamp methods, making it suitable for a wide range of applications in electrical testing and engineering.
2. Safety Information
Always adhere to local safety regulations and guidelines when operating this device. Failure to do so may result in injury or damage to the equipment.
- Ensure the device is in good working condition before use.
- Do not operate the tester in wet conditions or explosive atmospheres.
- Verify all connections are secure before initiating any measurement.
- Avoid touching live circuits.
- Use only the provided accessories or approved replacements.
- Keep the device away from strong electromagnetic fields.
3. Package Contents
Carefully unpack the ETCR3200C and verify that all items listed below are present and undamaged. If any items are missing or damaged, contact your supplier immediately.
Figure 3.1: Annotated view of the ETCR3200C package contents.
- ETCR3200C Ground Resistance Meter Unit
- Waterproof Protection Box
- Carrying Bag
- Auxiliary Grounding Rods (4 pieces)
- Current Clamps (2 pieces, Φ70mm jaw)
- Test Wires (Red, Green, Yellow, Black)
- Simple Testing Wire (Red/Black)
- USB Data Cable
- Power Adapter/Charger
- User Manual (this document)
Figure 3.2: All accessories included with the ETCR3200C tester.
4. Product Overview
The ETCR3200C features a robust design with a clear LCD display and intuitive controls. Understanding the various components is essential for proper operation.
Figure 4.1: Front panel and interface description of the ETCR3200C.
Key Components:
- LCD Display: Shows measurement readings, settings, and status indicators.
- Function Gear Knob: Used to select different measurement modes (e.g., Earth Resistance, Soil Resistivity, Earth Voltage, OFF).
- Function Key Area: Contains buttons for HOLD, MEM (Memory), AL (Alarm), CLR (Clear), READ, SET, and TEST.
- Input Terminals: Color-coded terminals (E, ES, P, C, C1, C2) for connecting test leads and auxiliary electrodes.
- Current Clamp Interfaces: Ports for connecting the two current clamps (CT1, CT2).
- Data Line Interface: USB port for data transfer to a computer.
- Charging Interface: Port for connecting the power adapter to charge the internal battery.
5. Setup and Connection Methods
The ETCR3200C supports various methods for measuring earth resistance and soil resistivity. Proper connection is crucial for accurate results.
Figure 5.1: Wiring diagrams for various measurement methods displayed on the inside lid of the ETCR3200C case.
5.1. 2-Wire, 3-Wire, and 4-Wire Methods (Earth Resistance)
These methods are used for measuring earth resistance, with the 4-wire method offering the highest accuracy by eliminating the resistance of the test leads.
- Preparation: Drive the auxiliary grounding rods (P and C) into the earth at appropriate distances from the grounding electrode (E) under test. Refer to the wiring diagram for recommended spacing.
- Connections:
- Connect the E terminal to the grounding electrode under test.
- Connect the P terminal to the potential auxiliary electrode.
- Connect the C terminal to the current auxiliary electrode.
- For 4-wire method, connect the ES terminal to the grounding electrode as well, ensuring separate connections for E and ES.
- For 3-wire method, connect E and ES together to the grounding electrode.
- For 2-wire method, connect P and C together to the auxiliary electrode, and E and ES together to the grounding electrode. This method is less accurate and generally used for quick checks or when auxiliary electrodes cannot be placed far enough.
- Select Mode: Turn the function knob to the desired Earth Resistance mode (e.g., 2/3/4-Wire).
5.2. Selection Method (Earth Resistance)
This method is used for measuring the earth resistance of a single grounding electrode in a multi-grounded system without disconnecting the grounding lead.
- Connections:
- Connect the E terminal to the grounding electrode under test.
- Connect the P and C terminals to auxiliary electrodes as in the 3-wire method.
- Attach one current clamp (CT1) around the grounding lead of the electrode under test.
- Select Mode: Turn the function knob to the 'Selection Method' Earth Resistance mode.
5.3. Double Clamp Method (Earth Resistance)
This method allows for non-contact measurement of earth resistance in multi-grounded systems without the need for auxiliary electrodes or disconnecting the grounding lead.
- Connections:
- Connect both current clamps (CT1 and CT2) to their respective ports on the tester.
- Clamp CT1 around the grounding lead of the electrode under test.
- Clamp CT2 around another grounding lead in the same multi-grounded system.
- Select Mode: Turn the function knob to the 'Double Clamp Method' Earth Resistance mode.
5.4. Soil Resistivity Measurement (ρ)
This measurement uses the 4-wire Wenner method to determine the resistivity of the soil, which is crucial for designing grounding systems.
- Preparation: Drive four auxiliary grounding rods (C1, P1, P2, C2) into the earth in a straight line, equally spaced. The spacing 'a' between rods is critical for calculation.
- Connections:
- Connect the C1 terminal to the outermost current electrode.
- Connect the P1 terminal to the inner potential electrode.
- Connect the P2 terminal to the other inner potential electrode.
- Connect the C2 terminal to the other outermost current electrode.
- Select Mode: Turn the function knob to the 'Soil Resistivity' mode.
- Input Spacing: The tester may require input of the rod spacing 'a' for accurate calculation. Refer to the on-screen prompts.
6. Operating Instructions
6.1. Powering On/Off
To power on the device, turn the function knob from 'OFF' to any desired measurement mode. To power off, turn the knob back to 'OFF'.
6.2. Performing Measurements
- Ensure the device is powered on and the correct measurement method is selected via the function knob.
- Make all necessary connections as described in Section 5.
- Press the TEST button to initiate the measurement.
- The measurement result will be displayed on the LCD.
- To hold the current reading, press the HOLD button. Press again to release.
6.3. Data Storage and Retrieval
The ETCR3200C can store up to 2000 sets of measurement data.
- After a measurement, press the MEM button to save the data.
- To recall stored data, turn the function knob to a memory recall mode (if available) or use the READ button in conjunction with other navigation keys.
- To clear data, use the CLR button.
- Data can be transferred to a computer via the USB data cable using the provided software (if applicable).
6.4. Earth Voltage and Earth Current Measurement
- Earth Voltage: Turn the function knob to 'AC V' mode. Connect the test leads to the desired points to measure AC voltage.
- Earth Current: Turn the function knob to 'AC A' mode. Use the current clamps to measure AC current flowing through grounding leads.
7. Measurement Parameters and Ranges
| Measurement Type | Range | Resolution | Accuracy |
|---|---|---|---|
| Earth Resistance (2/3/4-wire) | 0.00Ω - 300KΩ | 0.01Ω | ±2%rdg ±0.05dgt |
| Earth Resistance (Selection Method) | 0.00Ω - 3000Ω | 0.01Ω | ±2%rdg ±0.05dgt |
| Earth Resistance (Double Clamp Method) | 0.00Ω - 100Ω | 0.01Ω | ±10%rdg ±5dgt |
| Soil Resistivity (ρ) | 0.00Ωm - 9000KΩm | 0.01Ωm | |
| Earth Voltage (AC) | 0.0 - 100.0V AC | 0.1V | ±2%rdg ±3dgt |
| Earth Current (AC) | 0.0mA - 600.0A | 0.0mA | ±2%rdg ±3dgt |
8. Specifications
| Specification | Detail |
|---|---|
| Model Number | ETCR3200C |
| Brand | ETCR |
| Power Source | Battery Powered (Rechargeable Lithium Battery Pack) |
| Clamp Jaw Size | Φ70mm |
| Data Storage | 2000 Sets |
| Technology | FFT (Fast Fourier Transform Algorithm), AFC (Automatic Frequency Control) |
| Package Dimensions | 13.7 x 12.8 x 12.2 inches |
| Item Weight | 15.4 Pounds |
| Certification | CE |
9. Maintenance
- Cleaning: Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the tester in its waterproof protection box in a cool, dry place away from direct sunlight and extreme temperatures.
- Battery: Recharge the lithium battery pack regularly, especially if the device will not be used for an extended period, to maintain battery health.
- Calibration: For continued accuracy, periodic calibration by qualified personnel is recommended.
10. Troubleshooting
- No Power: Check battery charge. Ensure the function knob is turned to a measurement mode, not 'OFF'.
- Inaccurate Readings: Verify all test lead connections are secure and correct for the selected method. Ensure auxiliary electrodes are properly placed and making good contact with the earth. Check for strong electromagnetic interference.
- Display Error: Refer to the device's specific error codes (if any are displayed) in the full manufacturer's manual. Try restarting the device.
- Data Transfer Issues: Ensure the USB cable is correctly connected and the appropriate software is installed on your computer.
If problems persist, contact customer support.
11. Warranty and Support
This product comes with a standard manufacturer's warranty. Please refer to the warranty card included in your package or contact the seller for specific warranty terms and conditions.
For technical support, service, or inquiries, please contact your point of purchase or the manufacturer directly. Keep your purchase receipt and product model number handy when seeking support.
