Overview
The LMZB6-10Q/160 is an indoor epoxy cast-resin current transformer designed for 10kV, 11kV, and 12kV class medium-voltage switchgear. It features a fully enclosed epoxy resin body with a hollow through-window aperture, providing high insulation strength and mechanical stability for indoor applications.
This cable/busbar-through type CT supports rated primary currents from 1000A to 5000A and secondary currents of 5A or 1A. It is suitable for current measurement, energy metering, feeder monitoring, and relay protection in 50Hz or 60Hz AC power systems. The design complies with standard insulation coordination requirements for fixed metal-enclosed switchgear such as XGN-10 cabinets.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| Voltage class | 10kV / 11kV / 12kV |
| Rated insulation level | 12/42/75kV |
| Rated frequency | 50Hz / 60Hz |
| Rated primary current | 1000A – 5000A |
| Rated secondary current | 5A or 1A |
| Accuracy classes (metering) | 0.2(S), 0.5(S) |
| Accuracy classes (protection) | 5P10, 5P20, 10P10, 10P20 |
| Load power factor | 0.8 lagging |
Model Designation
- L: Current transformer
- M: Busbar / cable-through structure
- Z: Epoxy resin casting insulation
- B: Protection-class configuration available
- 6: Design sequence code
- 10: Rated voltage class: 10kV
- Q: Reinforced type
- 160: Aperture / inner-hole reference code
Construction
The LMZB6-10Q/160 features a fully enclosed epoxy cast-resin body that encapsulates the magnetic core and secondary winding. The primary conductor—either a cable or copper busbar—passes through the central hollow aperture without being wound, enabling use in high-current circuits. The cast-resin structure offers excellent insulation properties, moisture resistance, and surface cleanability for indoor environments. Equipotential shielding around the bus-window helps control electric field distribution during operation. Mounting is facilitated by four base holes, clearly marked terminals, and a dedicated grounding point, ensuring secure integration into fixed switchgear panels.
Technical Parameters
Service Conditions
- Installation location: indoor medium-voltage switchgear
- Rated voltage: 10kV, 11kV and 12kV class systems by project confirmation
- Rated frequency: 50Hz / 60Hz
- Ambient temperature: -5°C to +40°C
- Installation environment: should be free from severe vibration, corrosive gas, explosive medium, conductive dust, heavy pollution, and abnormal condensation.
- Special service conditions: for high altitude, coastal, humid or heavy-pollution service conditions, technical confirmation is recommended before ordering.
Technical Parameters
The LMZB6-10Q/160 is an epoxy cast-resin current transformer designed for indoor 10kV-class systems (compatible with 10kV, 11kV, and 12kV by project confirmation). It features a rated insulation level of 12/42/75kV, operates within an ambient temperature range of -5°C to +40°C, and complies with GB20840.2-2014 and IEC61869-2:2012 standards. The device supports primary current ranges from 1000A to 5000A with dual secondary windings for metering and protection applications.
| Rated Primary Current (A) |
Class Combination |
Accuracy Classes and Rated Output (VA) COSφ=0.8 |
|||
|---|---|---|---|---|---|
| 0.2(S) | 0.5(S) | 5(10)P10 | 5(10)P20 | ||
| 1000-1500 | 0.2(S)/0.2(S) 0.5(S)/0.5(S) 0.2(S)/5(10)P10(20) 0.5(S)/5(10)P10(20) 0.2(S)/0.5(S)/5(10)P10(20) |
20 | 20 | 30 | 15 |
| 2000-3000 | 20 | 20 | 50 | 20 | |
| 4000-5000 | 30 | 30 | 50 | 30 | |
Installation & Wiring
Installation Diagram
This cast-resin current transformer is designed for fixed installation in indoor metal-enclosed switchgear such as XGN-10 type cabinets. It is mounted using the provided fixing holes, with the primary conductor (cable or busbar) passing centrally through the aperture. Secondary terminals are accessible from the front or side as per the approved outline drawing, and equipotential bonding must be implemented where required by the switchgear design.
Selection & FAQs
Selection Guide
- Verify that the insulated conductor group fits the Ø160/162mm aperture with adequate centering, thermal expansion and electrical clearance.
- Select 1000A–1500A, 2000A–3000A or 4000A–5000A from continuous-current and fault-duty studies.
- Choose 1A or 5A and assign the two cores to 0.2(S)/0.5(S) measurement and 5P10/10P10 or 5P20/10P20 protection.
- Calculate each circuit burden at cosφ 0.8 and select the applicable 15VA–50VA output and metering FS.
- Approve the Ø286 body, 294×350mm mounting reference, four holes, equipotential connection, terminal access and +40°C environment.
Frequently Asked Questions
Q1: Where can this cast-resin current transformer be installed?
It is designed for indoor medium-voltage switchgear metering and protection. It supports 1000A to 5000A primary currents with dual secondary windings. Contact us for specific application details.
Q2: Can the LMZB6-10Q/160 operate in high-pollution areas?
Standard installation requires clean environments free from corrosive gases. For high-pollution or coastal conditions, the 12/42/75kV insulation must be verified. Technical confirmation is required before ordering.
Q3: Which accuracy class is required for protection relays?
Select 5P10 or 5P20 classes for protection applications. These classes ensure reliable performance during fault conditions per IEC 61869-2 standards. Specify your exact needs during inquiry.
Q4: What international standards does this 10kV CT comply with?
The transformer fully complies with IEC 61869-2:2012 and GB20840.2-2014 standards. It features a rated insulation level of 12/42/75kV. Request the full test certificate with your order.
Q5: How are factory tests conducted before shipment?
Routine tests verify insulation and accuracy per IEC 61869-2 standards. Special or type tests are subject to prior confirmation. Please contact our team to request the standard test protocol.
Q6: Are dual secondary windings included for metering and protection?
Yes, the LMZB6-10Q/160 features dual secondary windings. This allows simultaneous connection for both revenue metering and protective relaying within a single unit. Confirm the exact class combination during procurement.
Q7: Which voltage classes does this indoor current transformer support?
It is primarily rated for 10kV systems but is also compatible with 11kV and 12kV classes. Compatibility for higher voltages is subject to project confirmation. Specify your exact system voltage when ordering.