Flexible Cables Torque Test Device

1. Basic Understanding of Equipment

1.1 Scope of Equipment Application

This device is suitable for torque testing of flexible cables for household and similar uses.

It is primarily used in electrical product quality inspection laboratories, the quality control departments of manufacturers of plugs, sockets, and flexible cables, third-party testing organizations, and for the inspection of products entering or leaving the country.

1.2 Applicable Standards

Strictly in accordance with Clause 23.2 and Table 18 of GB/T 2099.1-2021 “Plugs and Sockets for Household and Similar Uses—Part 1: General Requirements” (Clause 23.2 of IEC 60884-1:2022, Table 21), and testing has been conducted.

Conduct torque tests on the flexible cable and its mounting components in accordance with the torque values and test durations specified in the standard.

1.3 Downloading Electronic Documents

We have already sent the download links for the digital user manual, calibration certificate, warranty card, and other documents via email at the time of shipment. Please download them as soon as possible. If you have not received the email, please contact us to request the download links again.

2. Precautions for Use

2.1 Operating Environment Safety Requirements

Operating environment temperature: 15°C to 35°C; relative humidity: 45% to 75%; no condensation, no corrosive gases, and no airborne dust.

Place the device on a level, stable workbench with at least 30 cm of clearance on all sides, away from sources of vibration.

2.2 Safety Guidelines for Operational Procedures

During testing, do not extend any body parts or other unrelated objects into the test area to prevent crush injuries or interference with the testing process.

The specimen must be securely clamped to prevent it from falling out or being ejected during the test.

Do not under any circumstances add additional weights to perform non-standard tests or forcefully rotate the torque disc, to prevent equipment damage and safety incidents.

3. Introduction to the Test Setup

See Figure 3-1.

Number	Note
①	Weights: one each of 2 N, 3 N, 5 N, 7 N, and 8.5 N, corresponding to torques of 0.1, 0.15, 0.25, 0.35, and 0.425 N·m, respectively.
②	A clamp used to secure components of a flexible cable, such as a plug or a portable receptacle
③	Flexible Cable Clamp, used to secure flexible cables
④	Chuck wrench, used to loosen or tighten the chuck
⑤	Torque disc, used to suspend weights in order to apply torque to the flexible cable and its mounting components

Figure 3-1

4. Torque Testing of Flexible Cable Mounting Components

4.1 Test Conditions

According to the standard, after completing the flexible cable tensile strength test (using the LS-B07 Retention Tensile Force Test Device for Soft Cable), the torque test on the flexible cable fasteners must be performed immediately.

4.2 Test Parameters

The flexible cable must be subjected to the torque for at least 1 minute.

See the table below for the torque test values of the flexible cable fasteners.

Rating of Plugs or Portable Power Strips	Flexible Cable (Number of Conductors × Nominal Cross-Sectional Area in mm²)
	2 × 0.5	2 × 0.75	3 × 0.5	3 × 0.75	(2 or more) × 1 or greater
≤16 A, 250 V	0.1 N·m	0.15 N·m		0.25 N·m	0.25 N·m
16 A and > 250 V	—	—	—	—	0.35 N·m
>16 A					0.425 N·m

4.3 Test Procedure

Refer to Chapter 3 for instructions on installing and securing the specimen. After suspending the appropriate weight on the torque plate as described in Section 4.2, begin the test and start the timer. Ensure that the weight does not sway and remains suspended in the air throughout the test. The test ends after 1 minute; remove the weight and take down the specimen.

4.4 Interpretation of Test Results

After completing the tensile and torque tests on the flexible cable, evaluate the results according to the following standards.

Plugs equipped with flat copper-clad flexible wires are not subjected to torque testing.

After the test, the displacement of the flexible cord shall not exceed 2 mm. For electrical accessories with detachable wires, the wire ends shall not show any noticeable movement within the terminals; for electrical accessories with non-detachable wires, the electrical connections shall not be disconnected.

To measure longitudinal displacement, make a mark on the flexible cable approximately 20 mm from the end of the test specimen or the cable protection device before the cable is subjected to tensile force.

For electrical accessories with non-detachable cords, if the test specimen has no clearly defined end or no flexible cable protection device, an additional mark must be made on the body of the test specimen.

While the flexible cable is under tension, measure the displacement of the markings on the cable relative to the test specimen or the cable protection device.

5. Post-Test Procedures

5.1 Device Reset

Remove the specimen and weights to prevent forces from being applied when the test is not in progress.

5.2 Sample Preparation

Separate the samples that passed and failed the test, label them clearly, and avoid mixing them up.

5.3 Cleaning and Tidying Up the Test Site

Use a lint-free, soft cloth to wipe away dust and debris from the surfaces of fixtures, chucks, brackets, and devices. Do not rinse the equipment directly with water.

Organize the tools and weights on the workbench, arrange them neatly, and clean up any debris left over from the experiment.

6. Routine Maintenance and Care

6.1 Regular Maintenance

Every 3 months, apply a small amount of neutral lubricating grease to critical parts, such as the torque disc bearings, to prevent rust and seizing.

6.2 Long-Term Storage and Maintenance

After routine maintenance is complete, cover the entire unit with a dust cover and store it in a dry, well-ventilated warehouse; coat the weights with rust-preventive oil and store them separately to prevent rust and deformation.

6.3 Calibration Interval Requirements

To ensure the accuracy and reliability of the device, it is recommended that it be sent periodically to a qualified third-party metrology laboratory for calibration. The recommended calibration interval is 12 months. Users may determine the specific calibration interval based on frequency of use, environmental conditions, and quality system requirements.

7. Troubleshooting and Resolving Common Issues

Fault Symptoms	Possible Causes	Procedure
The torque disc continues to rotate, and torque cannot be applied.	The specimen fixture end or chuck end is not securely fastened	Please refer to Chapter 3 and make sure both ends are securely fastened before trying again.
The torque disc cannot rotate; torque cannot be applied.	Torque Plate Bearing Seizure	Please refer to Section 6.1 for bearing maintenance to ensure that the torque disc rotates freely and without binding when no test specimen is installed.