LMZC(2,3)-10 Through-Core Cast-Resin Current Transformer 10kV Closed Type for Gas-Insulated Switchgear

The LMZC(2,3)-10 Through-Core Cast-Resin Current Transformer is a closed, cast-resin instrument transformer for 10 kV gas-insulated switchgear and similar distribution equipment. The series includes LMZC3-10 and LMZC2-10 designs. In either design, the primary conductor or cable passes through the transformer bore, while slotted mounting feet support installation in the switchgear assembly. This through-core arrangement gives engineers a defined mechanical interface for metering and protection circuits without presenting the product as a substitute for system-level design or commissioning review.

For a project team, the first question is not simply whether a current transformer has a 10 kV voltage class. The more useful question is whether the bore, primary-current range, secondary-current option, accuracy class, mounting space, and protection scheme fit the actual cubicle. The LMZC(2,3)-10 Through-Core Cast-Resin Current Transformer provides documented options that can be evaluated against those requirements. Final selection and relay settings should be confirmed by qualified electrical engineers against the project specification and applicable local requirements.

Core Technical Specifications

The stated technical conditions include a load power factor of cos φ = 0.8 lagging, Pollution Level II, ambient temperatures from −15 °C to +40 °C with a daily average not exceeding 30 °C, and altitude up to 1000 m. These are rated application conditions rather than a blanket approval for every environment. If a project has different ambient, altitude, clearance, or system conditions, the responsible engineering team should verify suitability before procurement.

Model Differences and Selection Logic

LMZC3-10 combines measuring and protective current-transformer functions. Its nominal bore is 82 mm and its outer diameter is 130 mm. LMZC2-10 adds a double-winding group and uses a 45 mm nominal bore within a 102 mm outer diameter. The double-winding accuracy options listed for LMZC2-10 are 0.25, 0.5, 10P10, and 10P5. The choice is therefore an engineering comparison of conductor passage, winding needs, and available switchgear space, rather than a claim that one model is universally better.

• Through-core primary: the primary conductor or cable passes through the bore.
• Closed cast-resin construction: the product is described as a closed, pouring-type transformer for the stated switchgear duty.
• Metering options: 0.2s, 0.2, and 0.5 measuring classes are listed.
• Protection options: 10P15, 10P10, and 10P5 protective classes are listed.
• Installation interface: slotted feet provide the documented mounting arrangement.

A datasheet match is only the beginning. A 50–600 A primary-current range and 5 A or 1 A secondary options are useful only after the connected meter, relay, burden, conductor, and protection-coordination requirements have been checked together. In particular, protection relay types and their settings should be reviewed as part of the connected system, because a current transformer selected in isolation does not establish a complete protection scheme.

Dimensions and Installation Considerations

Physical fit deserves the same attention as the electrical rating. A compact 33kv switchgear panel or a 10 kV enclosure may impose cable-entry, bend-radius, terminal-access, and maintenance-clearance constraints that are not solved by comparing nominal bore diameter alone. Confirm the conductor route, mounting-foot spacing, depth, and access before releasing a drawing or purchase order. This is especially important where the transformer is fitted into an existing cubicle.

Applications

The LMZC(2,3)-10 Through-Core Cast-Resin Current Transformer is intended for secondary metering and protection circuits in gas-insulated switchgear and compact 10 kV distribution switchgear. Suitable evaluation scenarios include metering circuits that require the listed 0.2s, 0.2, or 0.5 accuracy classes; protective relaying circuits that require the listed 10P15, 10P10, or 10P5 characteristics; and new-build or retrofit cubicles where the primary conductor passes through the bore.

Where LMZC2-10's double-winding arrangement is needed, engineers can compare the listed winding classes with the separate metering and protection duties of the project. For every application, verify burden, ratio, accuracy class, insulation coordination, terminal connections, and protection settings against the completed system design. A lightning impulse test or other specified test requirement should be confirmed for the exact project scope and applicable standard edition; it is not inferred merely from the series designation.

From a distribution system design perspective, the LMZC(2,3)-10 Through-Core Cast-Resin Current Transformer should be checked against conductor routing, secondary-circuit burden, enclosure clearance, and relay-coordination requirements before final approval.

Practical Procurement Checklist

1. Identify the required primary current from the available 50–600 A steps.
2. Confirm whether the secondary circuit requires 5 A or 1 A.
3. Select the measuring, protective, or double-winding accuracy configuration needed by the design.
4. Check bore diameter, outer diameter, mounting slots, body depth, and conductor routing against the cubicle layout.
5. Review environmental limits, applicable standards, and the required project test documentation.
6. Coordinate the current-transformer data with the meter, relay, and switchgear protection study before energization.

Commercial terms in the supplied product information state an MOQ of 1, T/T payment, and delivery within 20 days after receipt of payment. Availability, technical configuration, documentation, and delivery should be reconfirmed for the specific order. Contact the supplier with the required ratio, secondary current, accuracy class, burden, dimensions, and application details to obtain a project-specific technical proposal and quotation.