The choice between a separable connector and a heat shrink termination for switchgear and substation cables comes down to one question: does the cable connect to equipment, or does it terminate inside a substation? A separable connector — in practice the DS/SC series — plugs a medium-voltage cable into switchgear or a compact substation and keeps that interface separable. A heat shrink termination — the SY10kV, SY26kV or SY35kV series — closes off the cable end as an indoor terminal.

Both are medium-voltage cable accessories built for electric field control, insulation and sealing, and both go through the same factory electrical and partial discharge testing at Tonyhoo Cable Accessories. The decision is not about which product is stronger in general, but about interface fit, installation space, and the maintenance model a project will actually run.

Problem Definition: What Actually Separates the Two Products

The difference is structural, not cosmetic. A separable connector is designed to mate with equipment — switchgear bushings, compact substation enclosures — through a connection that can be taken apart for maintenance. A heat shrink termination is designed to finish a cable end for indoor service, where the cable stops and no repeat equipment interface is required.

That difference drives four practical selection parameters:

• Interface: does the cable attach to switchgear or equipment hardware?
• Installation space: is the installation location a tight switchgear compartment or a substation cable room with usable clearance?
• Maintenance model: will the connection need to be opened and reconnected during equipment servicing?
• Termination method: separable mating versus a fixed, installed termination built by heat application.

Where a project gets these four wrong, the cable accessory is the element that fails acceptance — not because the product was badly made, but because the wrong product class was specified for the connection type.

Separable Connector (DS/SC): Built for Switchgear and Compact Substation Connections

The DS/SC separable connector is used to connect a medium-voltage cable to switchgear, ring main units or compact substation equipment. Its function is to provide a separable equipment interface at the cable end.

For switchgear and compact substation work, the practical advantages are:

• Equipment interface fit. The connector is built to mate with the equipment at the cable termination point, which reduces the need for additional terminal hardware at the enclosure.
• Separability. The connection can be opened and re-made during equipment servicing, which suits switchgear that may need to be isolated or replaced.
• Compact installation. The separable design is intended for enclosed, space-constrained locations such as switchgear cable compartments and compact substations.

Tonyhoo manufactures the DS/SC separable connector as part of its medium-voltage cable accessories range. Selection is driven by the equipment interface requirement, cable cross-section and the rated voltage of the installation.

Heat Shrink Termination (SY10kV / SY26kV / SY35kV): Built for Indoor Substation Cable Ends

The SY10kV, SY26kV and SY35kV heat shrink terminations are used to terminate a medium-voltage cable end indoors. They are installed by applying heat to shrink the accessory onto the prepared cable.

For substation cable work, the practical characteristics are:

• Indoor termination function. The product closes the cable end where the cable stops inside a substation or an indoor cable compartment, with no repeating equipment interface.
• Voltage class coverage. The series is designated for 10kV, 26kV and 35kV classes, matching common medium-voltage distribution levels.
• Fixed termination. Unlike a separable connector, the termination is not designed to be opened and re-made as part of routine equipment servicing.

Tonyhoo manufactures the SY10kV, SY26kV and SY35kV heat shrink terminations within the same medium-voltage cable accessories range as the DS/SC connector.

Quality Assurance: The Tests That Apply to Both Product Classes

Product class determines fit; factory testing determines whether the delivered unit will hold up. Tonyhoo applies the same core electrical quality checks to both the separable connector and the heat shrink termination:

• 100% factory electrical test. Every unit is electrically tested; the check is applied unit by unit rather than by batch sampling.
• Partial discharge testing during production. Partial discharge testing is carried out as part of manufacturing, providing an insulation-quality check before shipment.
• Third-party inspection. SGS or TUV third-party inspection is available for buyers who require it.

For procurement, this matters because partial discharge behaviour is a key insulation indicator for medium-voltage accessories. An enquiry that asks for partial discharge records alongside the electrical test report is asking for evidence the factory already produces, rather than a special exercise.

Comparison Table: Separable Connector vs Heat Shrink Termination

The table below limits itself to characteristics that can be stated from documented product and factory facts. It is not a claim about every project condition.

Three points are worth pulling out of the table. First, the interface row is the deciding row: if the cable must mate with equipment, only a separable connector solves the problem. Second, the test rows are identical, so quality evidence should not be used to differentiate the two classes. Third, the commercial rows are identical, which means a project can compare both on the same terms sheet.

OEM and Customisation for Either Product Class

Tonyhoo provides OEM, ODM and customised solution production for its medium-voltage cable accessories. Both the DS/SC separable connector and the heat shrink termination series are available under the same OEM terms.

The customisation scope recorded for these products is:

• Rated voltage
• Cable cross-section
• Material formula
• Packaging
• Logo printing

Commercial terms relevant to an evaluation-stage enquiry are a minimum order quantity of 10 sets, a lead time of 30–40 days, and a monthly capacity of 12,000 sets. Private-label packaging and logo printing are supported, which suits distributors and brand owners building their own catalogue identity around the product.

The manufacturer operates from a 9,900㎡ factory with a 100-person team, including a 20-engineer R&D group, and reports an annual output of 200,000 units. Around 50% of output is exported, with the United States, Thailand, Vietnam, Albania and China listed as main markets.

Step-by-Step: Choosing Between the Two for a Project

Step 1 — Identify the connection type

Ask whether the cable terminates at equipment or terminates into open indoor space. Equipment termination points (switchgear, ring main unit, compact substation enclosure) indicate the separable connector. Open indoor cable ends in a substation indicate the heat shrink termination.

Step 2 — Confirm the voltage class

Match the accessory to the cable's rated voltage. For the heat shrink termination, the series designation (10kV, 26kV, 35kV) provides the first filter. For the separable connector, the equipment rating governs.

Step 3 — Review the installation space

Switchgear compartments and compact substations are typically space-constrained, which is where the separable connector's enclosed interface is designed to fit. Indoor cable rooms with usable clearance are the natural home of a fixed heat shrink termination.

Step 4 — Settle the maintenance model

If the project anticipates opening the cable connection during equipment servicing, the separable connector fits that model. If the cable end is a permanent termination, heat shrink is the appropriate class.

Step 5 — Confirm the cable parameters

Before requesting a quotation, confirm the rated voltage, cable model, conductor cross-section, core quantity and application environment (indoor, outdoor or direct burial). Complete parameters are what allow a supplier to match the accessory to the cable and confirm electric field control, sealing and compatibility.

Step 6 — Ask for the test evidence

Request the electrical test record and the partial discharge test record as part of acceptance. Confirm whether third-party inspection (SGS/TUV) is required, and whether it sits inside the acceptance criteria or as a separate check.

Step 7 — Align commercial terms

Confirm the OEM scope, minimum order quantity of 10 sets, 30–40 day lead time and any packaging or logo requirements against the project schedule.

Use Cases: Where Each Product Sits in Practice

Compact substations and switchgear cable compartments

The separable connector is the working choice wherever a medium-voltage cable must attach to equipment and stay separable. In compact substations, the combination of a tight enclosure and a required equipment interface makes the separable class the suitable one.

Indoor substation cable termination

The heat shrink termination is the working choice where an indoor cable end must be closed off. It supports substation cable termination where no repeat equipment interface is needed, and where the series voltage designation (10kV, 26kV or 35kV) matches the cable class.

Distribution networks with both connection types

Many distribution projects contain both connection types on the same site: separable connectors at the switchgear end and heat shrink terminations at the terminating cable ends. In that situation the two products are complementary, not alternatives, and the specification should list both.

Reference: Thailand PEA substation cable termination

For a Provincial Electricity Authority (PEA) substation project in Thailand, 1,000 units of indoor 10kV cable terminal support were supplied. The application was indoor cable termination supporting a substation, with the stated highlight being a compact structure suited to limited installation space inside substations, and the stated result being that the product met indoor distribution operation requirements and passed the local power authority's grid access test. This illustrates the indoor termination role that the heat shrink series is designed to serve.

FAQ

Conclusion: Choose by Connection Type, Then Verify by Test Evidence

The separable connector versus heat shrink termination decision is decided by connection type before anything else. Where a medium-voltage cable must attach to switchgear or a compact substation and remain separable for servicing, the DS/SC separable connector is the suitable class. Where a cable terminates indoors in a substation with no repeat equipment interface, the SY10kV, SY26kV or SY35kV heat shrink termination is the suitable class.

Once the class is settled, the two products should be evaluated on the same terms: 100% factory electrical testing, partial discharge testing during production, available third-party inspection, and an OEM scope covering rated voltage, cable cross-section, material formula, packaging and logo printing. With a minimum order quantity of 10 sets, a 30–40 day lead time and a monthly capacity of 12,000 sets, both classes can be assessed against the same project schedule. Requesting the electrical and partial discharge records as part of acceptance is the practical step that turns a specification into verified product.