1. Introduction
The UNI-T UT681C Cable Tester is a handheld device designed for quickly verifying the integrity of various network and communication cables. It can detect common wiring faults such as conducting, short-circuit, crossed, or open-circuit conditions in Ethernet (RJ45), telephone (RJ11), BNC, and HDMI cables. This manual provides essential information for the safe and effective use of your UT681C Cable Tester.
2. Safety Information
- Read all instructions carefully before operating the device.
- Do not expose the device to moisture or extreme temperatures.
- Use only the specified battery type and ensure correct polarity during installation.
- Do not attempt to repair or modify the device. Refer all servicing to qualified personnel.
- Disconnect all cables from the device before cleaning.
- Keep the device out of reach of children.
3. Product Overview
3.1 Key Features
- LED status display.
- Automatic detection of open, short, and crossover circuits.
- Simple single-key operation.
- Automatic power-off after 10 minutes of inactivity to conserve battery.
- Low battery indication for timely battery replacement.
- Supports testing of Ethernet (RJ45), telephone (RJ11), BNC, and HDMI cables.
3.2 Components
The UNI-T UT681C Cable Tester consists of two main units: the main tester unit and the remote unit. Both units feature various ports for different cable types and LED indicators for test results.
Figure 1: Front view of the UNI-T UT681C Cable Tester, showing the main unit (left) and remote unit (right) with BNC, RJ45, and RJ11 ports visible on the main unit.
Figure 2: Angled view of the UNI-T UT681C Cable Tester, highlighting the various cable ports (BNC, RJ45, RJ11) on both the main and remote units.
4. Setup
4.1 Battery Installation
- Locate the battery compartment on the back of the main tester unit.
- Open the battery compartment cover.
- Insert the required batteries (not included) according to the polarity markings inside the compartment.
- Close the battery compartment cover securely.
Note: The device requires batteries for operation. Ensure fresh batteries are installed for accurate testing.
4.2 Connecting Cables for Testing
To test a cable, connect one end to the corresponding port on the main tester unit and the other end to the corresponding port on the remote unit. For example, for an RJ45 Ethernet cable, connect one end to the RJ45 port on the main unit and the other end to the RJ45 port on the remote unit.
5. Operating Instructions
5.1 Power On/Off
- To power on the device, press the blue button labeled "开机/切换" (Power On/Switch) on the main unit.
- The device will automatically power off after 10 minutes of inactivity to conserve battery life.
- To manually power off, press and hold the "开机/切换" button for a few seconds.
5.2 Performing a Cable Test
- Ensure the cable to be tested is properly connected between the main unit and the remote unit.
- Power on the device by pressing the "开机/切换" button.
- The device will automatically begin testing the connected cable. The LED indicators will light up sequentially, indicating the status of each wire pair.
- Observe the LED display on both the main and remote units to interpret the test results.
5.3 Interpreting LED Indicators
The LED indicators correspond to individual wires or wire pairs within the cable. The sequence and pattern of the illuminated LEDs indicate the cable's condition:
- Sequential Illumination (1-8, G): Indicates proper continuity for each wire.
- No Illumination for a Specific LED: Suggests an open circuit or broken wire.
- Multiple LEDs Illuminating Simultaneously or Out of Sequence: Indicates a short circuit or crossed wires.
- "G" LED Illumination: Indicates ground wire continuity.
Refer to the specific wiring standards for RJ45 (T568A/B), RJ11, BNC, and HDMI to accurately diagnose complex wiring faults based on the LED patterns.
6. Maintenance
6.1 Cleaning
Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents, as these may damage the casing or internal components.
6.2 Storage
When not in use for extended periods, remove the batteries to prevent leakage and store the device in a cool, dry place, away from direct sunlight and extreme temperatures.
6.3 Battery Replacement
When the low battery indicator illuminates, replace the batteries promptly to ensure accurate readings and proper device function. Follow the battery installation steps outlined in Section 4.1.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Dead or incorrectly installed batteries. | Check battery polarity or replace with fresh batteries. |
| Inconsistent or no LED indications. | Loose cable connection; faulty cable; low battery. | Ensure cables are securely connected. Test with a known good cable. Replace batteries if low battery indicator is on. |
| Low battery indicator is on. | Batteries are depleted. | Replace all batteries with new ones. |
| Device powers off too quickly. | Automatic power-off feature; low battery. | This is normal after 10 minutes of inactivity. If it happens during active use, replace batteries. |
8. Specifications
- Model: UT681C
- Supported Cables: Ethernet (RJ45), Telephone (RJ11), BNC, HDMI
- Test Functions: Open circuit, short circuit, crossover, conducting
- Display: LED indicators
- Power Source: Battery Powered (Batteries not included)
- Auto Power Off: Approximately 10 minutes of inactivity
- Low Battery Indication: Yes
- Dimensions (L x W x H): 10.2 x 9.4 x 2.8 cm (Main Unit)
- Weight: Approximately 150 g
- Manufacturer: Uni-Trend Technology (China) Co., Ltd.
9. Warranty and Support
For warranty information, technical support, or service inquiries, please contact your original point of purchase or the manufacturer, Uni-Trend Technology (China) Co., Ltd. Keep your purchase receipt as proof of purchase.
