Product Overview
The LBZW-10 outdoor epoxy cast-resin current transformer is a medium-voltage outdoor CT designed for 11kV and 12kV class distribution systems. Unlike indoor cabinet CTs, this model is positioned for exposed or semi-exposed outdoor service where the transformer must withstand humidity, rain, dust, ultraviolet exposure and outdoor temperature variation. It is used for current measurement, energy metering and relay protection in overhead distribution lines, outdoor metering points, pole-mounted equipment, compact substations and outdoor switchgear.
The product adopts an outdoor epoxy cast-resin structure with two high-voltage bushing terminals on the top and a sealed secondary terminal box on the lower side. The fully insulated resin body and outdoor terminal structure provide a dry-type alternative to oil-filled outdoor CTs, reducing oil leakage risk and simplifying maintenance. For international product pages, the LBZW-10 should be described as an 11kV / 12kV outdoor medium-voltage current transformer with a rated insulation level of 12/42/75kV.
The key positioning of this product is not “general indoor CT”, but outdoor distribution metering and protection CT. It is suitable for projects where the CT is installed outside the switchgear room, on outdoor equipment platforms, in pole-mounted metering units, or at exposed distribution feeder points. The model supports 5A or 1A secondary output and common accuracy combinations such as 0.2/10P, 0.2S/10P and 0.5/10P.
Product Type
| Item | Specification |
|---|---|
| Product name | Outdoor Epoxy Cast-Resin Current Transformer |
| Model | LBZW-10 |
| Installation type | Outdoor medium-voltage distribution installation |
| Insulation type | Outdoor epoxy cast-resin structure with high-voltage bushing terminals |
| Voltage class | 11kV and 12kV class distribution systems |
| Rated insulation level | 12/42/75kV |
| Rated frequency | 50Hz; 60Hz available by project confirmation |
| Rated secondary current | 5A or 1A |
| Rated primary current | 5A to 600A reference range according to catalogue data |
| Typical functions | Current measurement, energy metering, relay protection and feeder monitoring |
Product Positioning
The LBZW-10 is best positioned as a compact outdoor dry-type CT for distribution metering and protection. It should not be written in the same style as indoor cast-resin cabinet CTs. Its value is in outdoor service reliability, sealed secondary wiring, weather-facing insulation structure and practical use in distribution networks where the CT may be installed near overhead lines, outdoor metering boxes or pole-mounted switchgear.
| Positioning Point | How to Express It | Why It Matters |
|---|---|---|
| Outdoor service | Outdoor epoxy cast-resin CT for 11kV / 12kV distribution systems | Clearly separates it from indoor switchgear CTs. |
| Dry-type insulation | Oil-free resin insulated design | Reduces oil leakage risk and simplifies maintenance. |
| Distribution metering | Suitable for outdoor feeder metering and energy measurement | Matches real field application better than generic CT wording. |
| Protection output | Metering core with 10P protection core options | Shows it can serve both revenue and protection circuits. |
| Compact outdoor equipment | Used with pole-mounted devices, outdoor metering units and compact substations | Makes the product page more specific and less homogeneous. |
Applications
- 11kV and 12kV outdoor medium-voltage distribution networks
- Outdoor feeder metering points and distribution line monitoring
- Pole-mounted metering units and outdoor metering cabinets
- Outdoor switchgear, compact substations and sectionalizing equipment
- Current measurement for distribution automation and SCADA input
- Relay protection circuits for outdoor distribution feeders
- Dry-type replacement projects where oil-filled outdoor CTs are not preferred
Features
- Outdoor CT positioning: Designed for exposed distribution applications rather than ordinary indoor switchgear installation.
- Epoxy cast-resin insulation: Oil-free dry-type construction supports stable insulation and avoids oil leakage maintenance issues.
- Weather-facing terminal structure: Two high-voltage bushing terminals are arranged on the top for outdoor primary connection.
- Sealed secondary terminal box: Secondary wiring is protected in a lower terminal box for safer field connection and maintenance.
- Metering and protection options: Accuracy combinations such as 0.2/10P, 0.2S/10P and 0.5/10P support both measuring and protection circuits.
- 11kV / 12kV IEC-oriented wording: 12/42/75kV insulation level supports international medium-voltage project documentation.
Operating Principle
The LBZW-10 outdoor current transformer converts the high primary current of an 11kV or 12kV distribution circuit into a standard secondary current signal, normally 5A or 1A. The primary conductor is connected through the outdoor high-voltage terminal structure. The secondary winding produces a proportional output for meters, relays or monitoring equipment.
For metering applications, the CT must maintain accuracy within the rated burden and specified accuracy class. For protection applications, the protection core must provide stable output under fault-current conditions. Therefore, the current ratio, rated output, accuracy class, short-time thermal current and dynamic current should be confirmed together before ordering.
Model Designation
| Code | Meaning |
|---|---|
| L | Current transformer |
| B | Outdoor / bushing-type structure reference |
| Z | Cast-resin insulation / epoxy casting structure |
| W | Outdoor service reference |
| 10 | Catalogue voltage class; documented internationally as 11kV / 12kV class by insulation confirmation |
Technical Data
| Item | Specification |
|---|---|
| Rated voltage class | 11kV and 12kV class outdoor distribution systems |
| Rated insulation level | 12/42/75kV |
| Rated frequency | 50Hz; 60Hz by project confirmation |
| Rated secondary current | 5A or 1A |
| Rated primary current | 5A–400A, 600A reference groups |
| Accuracy combinations | 0.2/10P, 0.2S/10P, 0.5/10P |
| Rated output | 0.2S: 10VA; 0.2/0.5: 10VA; 5P: 15VA; 10P: 15VA reference |
| Rated short-time thermal current | 60 × I1n for 5–400A; 50 × I1n for 600A reference |
| Rated dynamic current | 150 × I1n for 5–400A; 120 × I1n for 600A reference |
| Ambient temperature | -5°C to +55°C reference range |
| Applicable standards | IEC 61869-1, IEC 61869-2, GB/T 20840.1, GB/T 20840.2; project-specific requirements by agreement |
Selection Table
The following table is reorganized from the catalogue data for website use. Long headers are split into multiple lines to improve display on product pages.
| Rated
Primary Current (A) |
Accuracy
Class Combination |
Rated
Output (VA) |
Short-Time
Thermal Current |
Rated
Dynamic Current |
|---|---|---|---|---|
| 5–400 | 0.2 / 10P 0.2S / 10P 0.5 / 10P |
0.2S: 10 0.2 / 0.5: 10 5P: 15 10P: 15 |
60 × I1n | 150 × I1n |
| 600 | 50 × I1n | 120 × I1n |
Note: The table is intended for preliminary selection. Final current ratio, rated burden, accuracy class, terminal arrangement, insulation test and routine test requirements shall be confirmed according to the nameplate, approved drawing and factory test report.
Dimensions
| Dimension Item | Reference Value / Note |
|---|---|
| Overall height | Approx. 602mm reference from catalogue drawing |
| Top terminal spacing | Approx. 190 ± 5mm reference |
| Base length | Approx. 375mm reference |
| Base width | Approx. 255mm reference |
| Front lower width | Approx. 260mm reference |
| Secondary terminal box | Lower side terminal box; terminal direction must be confirmed before production |
Windings & Terminal Marking
The primary side is connected through the outdoor high-voltage terminals. The secondary terminal box is mounted on the lower side of the transformer body. Terminal marking should follow the approved wiring diagram and nameplate.
| Terminal | Function | Application Note |
|---|---|---|
| P1 / P2 | Primary terminals | Outdoor high-voltage primary connection; used for current direction and polarity reference. |
| 1S1 / 1S2 | First secondary winding | Usually used for metering or measurement circuit. |
| 2S1 / 2S2 | Second secondary winding | Usually used for protection relay circuit when a protection core is specified. |
| Grounding point | Protective grounding | One point of the secondary circuit should be grounded according to project practice. |
Service Conditions
- Installation location: outdoor medium-voltage distribution equipment
- Rated voltage: 11kV and 12kV class systems by project confirmation
- Rated frequency: 50Hz; 60Hz by agreement
- Ambient temperature: -5°C to +55°C reference range
- Installation should avoid continuous immersion, severe mechanical vibration and highly corrosive chemical environments unless specially specified.
- For coastal, high-humidity, high-altitude or heavy-pollution projects, creepage distance, sealing level and insulation coordination should be confirmed before ordering.
Standards and Compliance
For international product documentation, the LBZW-10 outdoor CT should be specified according to IEC 61869-1 and IEC 61869-2. For Chinese standard documentation, GB/T 20840.1 and GB/T 20840.2 can be used. Older catalogue or project references may be retained only when required by the customer or tender document.
Installation and Dimensions
The transformer should be mounted on a stable outdoor equipment platform or support frame. Before installation, confirm the primary terminal direction, conductor connection method, base mounting holes, grounding point, secondary cable outlet, creepage clearance and maintenance space. Secondary cables should be properly sealed and routed to prevent water ingress into the terminal box.
Safety Notes
- Confirm voltage class, insulation level, current ratio, secondary current, accuracy class and rated burden before production.
- Check primary terminal spacing, base mounting holes, grounding point and secondary terminal access before installation.
- Use suitable outdoor cable glands or sealing methods for secondary cable entry.
- The CT secondary circuit must not be open-circuited while primary current is flowing.
- Before disconnecting meters or relays, short-circuit the secondary circuit with an approved shorting device.
- One point of the secondary circuit should be reliably grounded according to local electrical safety regulations.
- Installation and commissioning shall be performed by qualified medium-voltage electrical personnel.
Ordering Info
- Product model: LBZW-10
- Voltage class: 11kV or 12kV class
- Rated primary current and transformation ratio
- Rated secondary current: 5A or 1A
- Accuracy class combination: metering + protection, such as 0.2/10P or 0.5/10P
- Rated output / burden for each secondary winding
- Rated short-time thermal current and dynamic current
- Outdoor installation environment: altitude, humidity, pollution level, coastal conditions if applicable
- Mounting drawing, primary terminal type, secondary terminal direction and cable outlet requirement
- IEC standard requirement, routine test report, certificate, label language and packaging requirement
Selection Guide
- Confirm outdoor use: Use LBZW-10 when the CT is installed outdoors or in exposed distribution equipment, not inside a closed indoor switchgear cabinet.
- Confirm voltage class: Use 11kV / 12kV wording with 12/42/75kV insulation level for international project pages.
- Select current ratio: Choose 5–400A or 600A range according to feeder load and metering range.
- Choose secondary current: Use 5A for conventional meters and relays; use 1A when secondary wiring burden must be reduced.
- Define accuracy combination: Use 0.2 or 0.2S for metering and 10P for protection circuits.
- Check outdoor conditions: Confirm creepage distance, sealing, cable outlet and corrosion exposure for humid or coastal installations.
- Approve drawings: Confirm base dimensions, terminal spacing, secondary terminal box and grounding point before production.