How to Select the Appropriate Cold Shrink Cable Joints for Power Cable Projects
In the power cable project, the selection of cold shrink cable joints is not only related to the compatibility of cable connection, but also affects the insulation protection, sealing effect and long-term operation reliability of the line. When selecting joints, we should not only consider the rated voltage or conductor cross-sectional area, but also consider the cable insulation outer diameter, cable structure, installation environment and product test requirements.
There are differences in cable specifications and operating conditions used in different projects. How to determine the appropriate type of cold shrinkable cable connector from the actual project parameters ? The following aspects are worth checking before placing an order.
Confirm the Rated Voltage of the Power Line:
The voltage level is the primary condition for the selection of cold shrinkable cable joints. The joint needs to match the rated voltage of the cable system and the highest equipment voltage, and cannot be simply judged according to the voltage level of the project.
At present, CCMT 's cold shrink cable joints cover 1kV to 36kV power systems and provide connection solutions for different voltage levels, including:
· 0.6 / 1kV ( 1.2kV ) : Suitable for low voltage cable connection.
· 8.7 / 15kV ( 17.5kV ) : Medium voltage cable system for the corresponding voltage class.
· 12 / 20kV ( 24kV ) : suitable for medium voltage distribution projects.
· 18 / 30kV ( 36kV ) : suitable for the corresponding level of high voltage cable connection requirements.
When making a purchase, it is recommended to first check the U₀/U (Uₘ) parameters in the project's technical specifications, and then confirm the rated voltage range applicable to the joint.
The Joint Is Matched with the Cross-Sectional Area of the Cable and the Diameter of the Insulating Layer.
After the voltage level is confirmed, the cable size is an important factor to determine whether the joint can be correctly installed. It is easy for buyers to focus only on the conductor cross-sectional area, but ignore the cable insulation outer diameter. In fact, even if the two cables have the same conductor cross-sectional area, their insulation materials, insulation thickness and production structure may also be different, resulting in differences in the outer diameter of the insulation.
Taking the cold shrink cable joints of CCMT as an example:
| Rated Voltage | Cable Cross Section | Insulation Diameter |
| 0.6/1kV | 25–50 / 70–120 / 150–240 / 300–400mm² | To Be Confirmed According to the Specific Model |
| 8.7/15kV | 25–50 / 70–120 / 150–240 / 300–400 / 500–630mm² | 16–19.5 / 19–27.5 / 23.5–30 / 30.5–35 / 37–42.3mm |
| 12/20kV | 25–50 / 70–120 / 150–240 / 300–400 / 500–630mm² | 18–22.5 / 21–26.5 / 25.5–32 / 32.5–37 / 39–44.5mm |
| 18/30kV | 35–50 / 70–120 / 150–240 / 300–400 / 500–630mm² | 22–28 / 26.5–33 / 31.5–43 / 35.5–43 / 40.5–49mm |
The above is the corresponding parameter range of different specifications, and the actual selection should be checked item by item according to the product model.
In addition, it should also be confirmed whether the cable is single-core or three-core. We provide the corresponding single-core and three-core connector models. When purchasing, we need to determine the product configuration in combination with the actual cable structure.
Consider the Cable Structure and Installation Conditions.
In addition to electrical parameters and dimensions, cable structure and installation environment will also affect the selection of joints.
First of all, it is necessary to confirm the insulation type, metal shielding structure, outer sheath and grounding connection mode of the cable. Different cable structures have different requirements for the internal components, stress control and shielding connection of the joint.
Secondly, the applicability of the joint should be confirmed according to the project site conditions. For example, underground cable lines need to focus on the waterproof and moisture-proof sealing capabilities of joints; outdoor power distribution projects need to consider weather resistance and long-term environmental exposure conditions ; the power supply lines of industrial plants and equipment may also face factors such as chemical media and complex construction space.
The cold shrink cable joints adopt a pre-expanded silicone rubber structure, and the radial pressure is formed by the elastic retraction of the material itself during installation, without the use of open flame or heating equipment. This feature can reduce the dependence on heating tools on site, and is suitable for environments with limited construction space or unsuitable for open fire operations.
Common Errors in Purchasing:
In the actual procurement process, some seemingly small parameters are missed, which may lead to the wrong selection of joint models and increase the subsequent technical confirmation and on-site construction costs.
1. Selection only based on the cross-sectional area of the conductor
2. Ignore the cable structure
3. neglect the installation environment
4. Inspect the certificate without verifying the test report
What Should Be Verified Before Purchase?
After determining the product model, it is also necessary to audit the supplier 's technical data and quality verification capabilities. It is recommended to focus on verifying the following:
· Product technical data
Suppliers can be required to provide product specifications for the corresponding model, confirming information such as rated voltage, applicable conductor cross-sectional area, insulation outer diameter range, single-core or three-core configuration.
· Test report
For medium and high voltage cable joints, attention should be paid to the relevant type test reports issued by independent third-party laboratories, including the test data of cold-shrinkable cable terminals and joints. The purchaser should confirm whether the product category, model and applicable voltage level corresponding to the report meet the project requirements.
· Quality management and product certification
CCMT has established ISO9001 : 2015 quality management system, and has CE, SGS and other related certification and information, and the products meet the environmental requirements of RoHS and REACH. We also hold a type test report of cold-shrinkable cable terminals and intermediate joints issued by an independent third-party laboratory.
· Manufacturing and Supply Capabilities
In addition to the product itself, the supplier 's production capacity will also affect project delivery. CCMT has a production base of more than 10,000 square meters, equipped with a variety of production equipment, and a monthly supply capacity of about 20,000 cold-shrinkable cable joints, which can provide supply support for overseas procurement projects of different scales.
Choose the right cold shrink cable joints, from the project voltage level, cable cross-sectional area, insulation outer diameter, cable structure and installation environment and other aspects of the verification, and can not be determined by a single parameter model.
CCMT provides cold shrink cable joints covering 1kV to 36kV power systems and supports the confirmation of product specifications according to project requirements. Whether it is a conventional power distribution project or an industrial cable connection demand, the purchaser can provide information such as cable voltage level, cross-sectional area, and insulation outer diameter to further confirm the applicable model and technical requirements.
