Product Overview
The LFZ1D-0.66 state grid metering current transformer is an indoor unsaturated cast-resin low-voltage current transformer designed for current measurement and electrical energy metering in AC systems with rated voltage up to 0.66kV and rated frequency of 50Hz. The product is used to transmit metering signals and provide electrical isolation between high-current primary circuits and metering or monitoring equipment.
The LFZ1D-0.66 series is mainly used in low-voltage metering cabinets, distribution panels, grid metering boxes, and energy measurement circuits. The product adopts a cast-resin insulated structure with fixed installation, and is suitable for indoor low-voltage metering applications where stable measurement accuracy and compact cabinet installation are required.
Product Type
| Item | Specification |
|---|---|
| Product name | State Grid Metering Low Voltage Current Transformer |
| Model series | LFZ1D-0.66 |
| Product structure | Indoor unsaturated cast-resin type, fixed installation |
| Rated voltage class | 0.66kV and below low-voltage AC system |
| Rated frequency | 50Hz |
| Rated secondary current | 5A |
| Installation location | Indoor |
| Typical applications | Current measurement, electrical energy metering, grid metering cabinets, low-voltage distribution monitoring |
Product Display
Main Applications
- State grid low-voltage metering applications
- Indoor AC circuits rated up to 0.66kV and 50Hz
- Energy metering cabinets and low-voltage metering boxes
- Current measurement and electrical energy measurement circuits
- Distribution cabinets and power monitoring panels
- Metering signal acquisition and isolation for low-voltage power systems
Key Technical Features
- Grid metering design: Designed for low-voltage current measurement and electrical energy metering applications.
- Cast-resin insulation: The indoor unsaturated cast-resin structure supports insulation performance, mechanical strength, and stable fixed installation.
- 5A secondary output: Suitable for common energy meters, metering terminals, and measuring instruments.
- Compact indoor structure: Suitable for metering cabinets and low-voltage distribution panels where installation space is limited.
- Metering accuracy options: Accuracy classes such as 0.5S and 0.2S are available according to current ratio and project requirements.
Working Principle
The LFZ1D-0.66 current transformer operates according to electromagnetic induction. When primary current flows through the primary conductor of the transformer, magnetic flux is generated in the magnetic circuit. The secondary winding outputs a proportional 5A current signal for connected energy meters or measuring instruments. This enables safe measurement and electrical isolation in low-voltage metering systems.
Model Designation
The model code can be interpreted as follows:
| Code | Meaning |
|---|---|
| LFZ1D | Low-voltage cast-resin metering current transformer series |
| 0.66 | Rated voltage class: 0.66kV |
| D | Metering application / dedicated metering design code |
Technical Data
| Item | Specification |
|---|---|
| Rated voltage | 0.66kV / 660V |
| Rated frequency | 50Hz |
| Rated primary current | 10A to 100A according to catalogue data; other ratios can be confirmed by technical agreement |
| Rated secondary current | 5A |
| Accuracy class | 0.5S / 0.2S according to selected specification |
| Rated secondary burden | 5/2.5VA according to selected accuracy class and specification |
| Installation method | Indoor fixed installation |
| Insulating medium | Unsaturated cast resin |
| Applicable standards | GB/T 20840.1, GB/T 20840.2, Q/GDW 1572; project-specific requirements can be confirmed by agreement |
Rated Current, Accuracy and Output Reference
| Model | Rated Primary Current (A) | Rated Secondary Current (A) | Rated Burden 0.5S (VA) | Rated Burden 0.2S (VA) |
|---|---|---|---|---|
| LFZ1D-0.66 | 10, 15, 20, 25, 30, 40, 50, 60, 75, 100 | 5 | 5 / 2.5 | 5 / 2.5 |
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
- Ambient temperature: -5°C to +40°C
- Relative humidity: not more than 80%
- Altitude: not more than 1000m unless otherwise specified
- The installation environment should be free from metal dust, severe vibration, conductive dust, corrosive gas, explosive medium, and heavy pollution.
- For special altitude, humidity, metering cabinet layout, or installation space requirements, technical confirmation is recommended before ordering.
Standards and Compliance
The LFZ1D-0.66 current transformer is designed for low-voltage metering current transformer applications and can be supplied according to GB/T 20840.1, GB/T 20840.2, Q/GDW 1572, and customer-specific technical requirements. For state grid metering projects or special acceptance requirements, the final standards, test items, nameplate data, and inspection documents should be confirmed in the technical agreement.
Installation and Dimensions
The LFZ1D-0.66 series adopts a compact indoor cast-resin structure for fixed installation in low-voltage metering cabinets and distribution panels. The following dimension data is for product selection and cabinet layout reference. Final dimensions should be confirmed according to the approved drawing before production or batch ordering.
Overall Dimensions Reference
| Model | L (mm) | W (mm) | H (mm) | Drawing Reference |
|---|---|---|---|---|
| LFZ1D-0.66 | 100 | 118 | Subject to final drawing | Catalogue drawing / approved drawing |
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 burden, and outline structure before installation.
- Check that the primary conductor and cabinet layout match the selected CT structure.
- Install the product by fixed mounting according to the approved metering cabinet or distribution panel layout.
- 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, sealing, and terminal protection should comply with metering 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: LFZ1D-0.66
- Rated primary current and rated secondary current
- Accuracy class and rated secondary burden
- System frequency and installation environment
- Quantity and metering cabinet application
- Special requirements for bar code, asset number, electronic label, terminal sealing, drawings, inspection documents, certificates, or packaging
Selection Guidelines
- Confirm system voltage: Select this CT for indoor low-voltage AC systems rated up to 0.66kV.
- Confirm metering application: Determine whether the product is used in a grid metering cabinet, distribution cabinet, or energy metering box.
- Confirm current ratio: Select the rated primary current according to the normal operating current and metering range of the circuit.
- Select accuracy class: Use 0.5S or 0.2S according to the metering accuracy requirement and project specification.
- Confirm rated burden: The total burden of the energy meter, terminal wiring, and secondary cable should not exceed the rated secondary burden of the CT.
- Confirm installation dimensions: Check the outline drawing, terminal position, and cabinet clearance before batch installation.