Product Overview
The LQZ5-0.66 solid cast-resin low-voltage current transformer is an indoor busbar-type current transformer designed for current measurement, energy metering, electrical monitoring, and relay protection in AC circuits with rated voltage up to 0.66kV. The product adopts a fully enclosed cast-resin structure, with the core and secondary winding encapsulated in epoxy resin to provide insulation performance, mechanical strength, and moisture resistance.
The LQZJ4-0.66, LQZ5-0.66 Solid Cast-Resin Current TransformerLQZ5-0.66 series is suitable for low-voltage distribution cabinets, metering panels, power monitoring systems, industrial electrical equipment, and mining-related electrical installations. It is a small fixed-type current transformer installed by baseplate fixing or busbar mounting, and can provide a standard 5A or 1A secondary current signal for meters, instruments, relays, or monitoring devices.
Product Type
| Item | Specification |
|---|---|
| Product name | Solid Cast-Resin Low Voltage Current Transformer |
| Model series | LQZ5-0.66 LQZJ4-0.66, |
| Product structure | Indoor cast-resin, busbar type, small fixed type |
| Phase | Single phase |
| Rated voltage class | 0.66kV low-voltage AC system |
| Rated frequency | 50Hz / 60Hz according to project requirement |
| Rated secondary current | 5A or 1A |
| Insulating medium | Epoxy resin / cast resin |
| Installation location | Indoor |
| Typical applications | Current measurement, energy metering, monitoring, display recording, relay protection |
Product Display
Main Applications
- Low-voltage AC distribution systems rated up to 0.66kV
- Indoor metering cabinets and power distribution panels
- Energy metering, current measurement, and electrical monitoring circuits
- Display recording and current control systems
- Relay protection and low-voltage protection circuits
- Industrial electrical systems and mining-related electrical equipment
- Busbar-type current sensing applications requiring a compact fixed installation structure
Key Technical Features
- Solid cast-resin insulation: The core and winding are encapsulated in epoxy resin to support insulation performance, moisture resistance, and mechanical stability.
- Compact fixed structure: The small fixed-type design is suitable for installation in low-voltage cabinets and compact electrical panels.
- Busbar-type installation: The product is designed for busbar connection and can be installed by baseplate fixing according to cabinet layout.
- Wide current range: Rated primary current options cover low-voltage measurement applications from small current circuits to higher busbar currents.
- Multiple accuracy classes: Accuracy classes such as 0.2, 0.2S, 0.5, and 0.5S are available according to metering or monitoring requirements.
- Standard secondary output: 5A or 1A secondary current can be selected according to connected instruments, relays, or project requirements.
Working Principle
The LQZJ4-0.66, LQZ5-0.66 current transformer operates according to electromagnetic induction. When primary current flows through the busbar or primary conductor, magnetic flux is generated in the core. The secondary winding outputs a proportional current signal, normally rated at 5A or 1A, for connected meters, instruments, relays, or monitoring devices. This allows the primary current in a low-voltage circuit to be converted into a standardized secondary current signal for safe measurement, metering, and protection.
Model Designation
The model code can be interpreted as follows:
| Code | Meaning |
|---|---|
| L | Current transformer category |
| Q | Coil / winding type structure |
| Z | Cast-resin insulation structure |
| 5 | Design series / product structure code |
| 0.66 | Rated voltage class: 0.66kV |
Technical Data
| Item | Specification |
|---|---|
| Rated voltage | 0.66kV / 660V |
| Rated frequency | 50Hz / 60Hz |
| Rated primary current | 5A to 600A according to catalogue data; other ratios can be confirmed by technical agreement |
| Rated secondary current | 5A or 1A |
| Accuracy class | 0.2, 0.2S, 0.5, 0.5S; subject to selected ratio and order requirements |
| Rated output | 5VA or 10VA according to current ratio and specification |
| Rated insulation level | 0.66/3kV |
| Ambient temperature | -5°C to +55°C according to catalogue data; standard indoor conditions may be confirmed by project requirement |
| Installation method | Baseplate fixing / busbar type installation |
| Insulating medium | Epoxy resin / cast resin |
| Applicable standards | GB/T 20840.2-2014, IEC 61869-2:2012, IEC 60044-1:2003; project-specific requirements can be confirmed by agreement |
Rated Current, Accuracy and Output Reference
| Rated Primary Current (A) | Rated Secondary Current (A) | Accuracy Class | Rated Output (VA) |
|---|---|---|---|
| 5, 10, 15, 20, 30, 40, 50, 75, 100 | 5 / 1 | 0.2 / 0.2S / 0.5 / 0.5S | 5 / 10 |
| 150, 200, 250, 300, 400 | 5 / 1 | 0.2 / 0.2S / 0.5 / 0.5S | 5 / 10 |
| 500, 600 | 5 / 1 | 0.2 / 0.2S / 0.5 / 0.5S | 5 / 10 |
Note: Technical parameters beyond the above range can be confirmed through technical agreement between manufacturer and purchaser.
Service Conditions
- Installation location: indoor
- System voltage: 0.66kV and below
- Rated frequency: 50Hz / 60Hz according to order requirement
- Ambient temperature: -5°C to +55°C according to catalogue data; daily average temperature should not exceed the specified service condition
- Power factor of rated burden: 0.8 lagging unless otherwise specified
- The surrounding atmosphere should be free from severe pollution, corrosive gas, explosive medium, conductive dust, and heavy moisture.
- For special altitude, humidity, pollution level, mining application, or cabinet layout requirements, technical confirmation is recommended before ordering.
Standards and Compliance
The LQZ5-0.66 current transformer is designed for low-voltage current transformer applications and can be supplied according to GB/T 20840.2-2014, IEC 61869-2:2012, IEC 60044-1:2003, and customer-specific technical requirements. For projects requiring special testing items or updated standards, the final requirements should be confirmed in the technical agreement.
Installation and Dimensions
The LQZ5-0.66 series adopts a compact cast-resin structure with busbar-type installation. The following outline dimensions are for product selection and cabinet layout reference. Final dimensions should be confirmed according to the approved drawing before production or batch ordering.
Outline Drawing Reference
Rated Current Range and Outline Reference
| Rated Primary Current Range | Main Outline Reference | Installation Reference | Remark |
|---|---|---|---|
| 5A–400A | Approx. 125±1 mm width, 119±2 mm height | Busbar / baseplate mounting; overall installation length approx. 174±2 mm | Refer to approved drawing before cabinet design |
| 400A–600A | Approx. 130±1 mm width, 124±2 mm height | Busbar / baseplate mounting; overall installation length approx. 204±2 mm | Refer to approved drawing before cabinet design |
Unit: mm. Final dimensions are subject to confirmed drawing and selected specification.
Installation and Safety Notes
- Confirm the CT model, current ratio, accuracy class, rated output, and installation dimensions before installation.
- Check that the busbar or primary conductor matches the selected CT structure and mounting layout.
- Install the CT by baseplate fixing or busbar mounting according to the cabinet design.
- Connect secondary terminals according to polarity marks such as S1 and S2 and the project wiring diagram.
- The secondary circuit of a current transformer must not be open-circuited when the primary circuit is energized.
- Secondary wiring, grounding, and terminal protection should comply with project specifications and local electrical regulations.
- Installation and maintenance should be performed by qualified electrical personnel.
Ordering Information
Please provide the following information when ordering or requesting a quotation:
- Product model: LQZ5-0.66
- Rated primary current and rated secondary current
- Accuracy class: 0.2, 0.2S, 0.5, or 0.5S
- Rated output / burden in VA
- System frequency and installation environment
- Installation method and cabinet layout requirement
- Quantity and application, such as metering, monitoring, or relay protection
- Special requirements for terminal arrangement, labels, drawings, inspection documents, certificates, or packaging
Selection Guidelines
- Confirm system voltage: Select this CT for low-voltage AC systems rated up to 0.66kV.
- Confirm application: Determine whether the transformer is used for metering, current monitoring, display recording, current control, or relay protection.
- Confirm current ratio: Select the primary current according to the normal operating current and measurement range of the circuit.
- Select secondary current: Choose 5A for common short-distance metering circuits, or 1A when required by the meter, relay, or secondary wiring design.
- Select accuracy class: Use 0.2 or 0.2S for higher metering requirements, and 0.5 or 0.5S for general measurement or monitoring applications.
- Confirm rated burden: The total burden of meters, relays, instruments, and secondary wiring should not exceed the rated output of the CT.
- Confirm installation dimensions: Check the outline drawing and mounting space before switchgear layout or batch installation.