Product Overview
The LZZB(J)6-12Q / LZZJB6-12Q current transformer is an indoor single-phase epoxy cast-resin current transformer for medium-voltage switchgear. It is designed for current measurement, energy metering, relay protection, and feeder monitoring in AC power systems. For international project documentation, the product should be positioned as a 12kV class current transformer, suitable for common 10kV, 11kV and 12kV class indoor switchgear applications after insulation coordination is confirmed.
This product family includes several closely related catalogue names, such as LZZBJ9-10X, LZZB6-12Q, LZZBJ6-12Q, and LZZJB6-12Q. For a clean website structure and better SEO, it is recommended to use LZZB(J)6-12Q as the main product name, and mention LZZJB6-12Q as a related structural variant. This avoids creating multiple duplicated product pages for models that are technically similar and used in the same indoor 12kV switchgear application range.
The transformer adopts an indoor epoxy resin casting structure with integrated primary terminals, secondary terminal blocks, and a compact base plate for switchgear installation. The resin-cast body provides insulation strength, mechanical stability, and moisture resistance. The product can be configured with 5A or 1A secondary current, metering accuracy classes such as 0.2 / 0.2S / 0.5 / 0.5S, and protection classes such as 5P10, 5P15, 10P10 and 10P15.
Recommended Model Name
| Website Field | Recommended Wording |
|---|---|
| Main product model | LZZB(J)6-12Q |
| Related variant | LZZJB6-12Q |
| Legacy / catalogue reference | LZZBJ9-10X, LZZB6-12Q, LZZBJ6-12Q |
| Recommended product name | LZZB(J)6-12Q Indoor Epoxy Cast-Resin Current Transformer |
| SEO positioning | 12kV indoor cast-resin CT for 10kV, 11kV and 12kV switchgear |
Product Type
| Item | Specification |
|---|---|
| Product name | Indoor Single-Phase Epoxy Cast-Resin Current Transformer |
| Model series | LZZB(J)6-12Q / LZZJB6-12Q |
| Structure | Indoor epoxy cast-resin structure with primary terminals and secondary terminal block |
| Voltage class | 12kV class; suitable for 10kV, 11kV and 12kV class indoor systems by project confirmation |
| Rated insulation level | 12/42/75kV |
| Rated frequency | 50Hz or 60Hz |
| Rated secondary current | 5A or 1A |
| Rated primary current | 20A to 1500A depending on model variant and specification |
| Typical use | Current measurement, energy metering, relay protection, switchgear monitoring |
Product Display
The LZZB(J)6-12Q series has a compact vertical epoxy cast-resin body with primary terminals on the top side and secondary terminals at the lower front side. The LZZJB6-12Q version follows a similar indoor cast-resin design, but the structure and current range can be different depending on the selected model. Both are suitable for fixed indoor switchgear, metering panels, feeder cabinets, and compact medium-voltage distribution equipment.
Applications
- 10kV, 11kV and 12kV class indoor medium-voltage switchgear
- Fixed metal-enclosed switchgear, metering cabinets and feeder panels
- Current measurement and electric energy metering circuits
- Relay protection circuits using 5P or 10P protection classes
- Industrial substations, commercial power rooms and utility distribution systems
- OEM switchgear projects requiring compact 12kV indoor cast-resin CTs
Features
- Optimized model grouping: LZZB(J)6-12Q is used as the main page model, while LZZJB6-12Q and legacy 10X names are treated as related variants.
- 12kV class insulation design: The 12/42/75kV insulation level supports common 10kV, 11kV and 12kV class indoor switchgear applications.
- Epoxy cast-resin body: The cast insulation provides mechanical strength, dielectric stability, and moisture resistance for indoor service.
- Measurement and protection options: Metering classes 0.2, 0.2S, 0.5 and 0.5S can be combined with 5P or 10P protection classes.
- 5A or 1A secondary output: 5A is suitable for conventional relay and metering systems, while 1A reduces secondary burden for longer wiring or digital devices.
- Compact cabinet installation: The vertical structure is suitable for indoor switchgear where space, wiring access, and terminal direction must be controlled.
Principle
The LZZB(J)6-12Q / LZZJB6-12Q current transformer operates by electromagnetic induction. The primary current flows through the primary conductor path and produces magnetic flux in the internal core. The secondary winding then outputs a proportional 5A or 1A current signal for meters, protection relays, or monitoring devices.
For metering applications, the transformer must maintain ratio accuracy and phase displacement within the rated burden. For protection applications, the protection core must provide a reliable current signal under fault-current conditions. Therefore, the current ratio, secondary current, rated output, accuracy class, short-time thermal current and dynamic current should be selected together with the switchgear and relay protection design.
Model Designation
| Code | Meaning |
|---|---|
| L | Current transformer |
| Z | Cast-resin insulation / epoxy casting structure |
| ZB / ZZB | Indoor cast-resin current transformer structure series |
| J | Enhanced or structural variant reference, depending on manufacturer drawing |
| 6 | Design sequence code |
| 12Q | 12kV class reinforced / compact indoor structure reference |
| LZZJB6-12Q | Related variant with similar voltage class and indoor cast-resin application |
| LZZBJ9-10X | Legacy or related catalogue reference that can be redirected to this product family |
Technical Data
| Item | Specification |
|---|---|
| Rated voltage class | 12kV class; suitable for 10kV, 11kV and 12kV class indoor systems |
| Rated insulation level | 12/42/75kV |
| Rated frequency | 50Hz or 60Hz |
| Rated secondary current | 5A or 1A |
| Rated primary current | 20A to 1500A depending on variant and order requirement |
| Accuracy classes | 0.2, 0.2S, 0.5, 0.5S, 5P10, 5P15, 10P10, 10P15 |
| Rated output | 10VA, 15VA, 20VA or project-specific output according to current ratio and accuracy class |
| Short-time thermal current | 150 × I1n, 80 × I1n or kA-level values depending on ratio and variant |
| Rated dynamic current | 375 × I1n or kA-level values depending on ratio and variant |
| Approximate weight | About 19.5kg reference for one catalogue variant |
| Applicable standards | IEC 61869-2, GB20840.2-2014, and project-specific requirements |
Selection Table
The following table combines the visible catalogue data into a website-friendly selection format. Long headers are wrapped to improve responsive layout.
| Model
Variant |
Rated
Primary Current (A) |
Class
Combination |
Rated
Output |
Short-Time
Thermal Current |
Dynamic
Current |
|---|---|---|---|---|---|
| LZZB6-12Q | 20–100 | 0.2(S) / 0.5(S) 0.2(S) / 10P 0.5(S) / 10P |
0.2(S): 10 0.5: 10 5P10 / 10P10: 15 |
150 × I1n | 375 × I1n |
| 150 | 0.2(S): 10 0.5: 10 Protection: 15 |
22.5kA | 44kA | ||
| 200–300 | 0.2(S): 10 0.5: 10 Protection: 15 |
24.5kA | 44kA | ||
| LZZJB6-12Q | 20–100 | 0.2(S) / 0.5(S) 0.2(S) / 10P 0.5(S) / 10P |
0.2(S): 10 0.5: 15 Protection: 15 |
150 × I1n | 375 × I1n |
| 150 | 0.2(S): 10 0.5: 15 Protection: 15 |
22.5kA | 44kA | ||
| 200–300 | 0.2(S): 10 0.5: 15 Protection: 15 |
24.5kA | 44kA | ||
| 400–600 | 0.2(S): 10 0.5: 15 Protection: 15 |
33kA | 59kA | ||
| 800–1500 | 0.2(S): 10 0.5: 15 Protection: 15 |
44kA | 74kA | ||
| LZZBJ9-10X | 5–1000 | 0.2 / 0.2 0.2 / 0.5 0.2 / 10P 0.5 / 10P |
0.2: 10 0.5: 10 10P: 15 |
80 × I1n or kA-level values | 200 × I1n or kA-level values |
Note: The table is intended for preliminary model selection. Final current ratio, accuracy class, rated output, thermal current, dynamic current, dimensions and terminal arrangement shall be confirmed according to the approved drawing and nameplate.
Variant Selection
| Variant | Best Use | Technical Note |
|---|---|---|
| LZZB6-12Q | Compact 12kV indoor CT for lower and medium primary current ranges | Suitable when a compact resin-cast body and standard 12kV switchgear insulation level are required. |
| LZZBJ6-12Q | Related structural version for indoor 12kV applications | Can be included as a cross-reference if customer drawings or tenders use this designation. |
| LZZJB6-12Q | Wider current range and higher-current feeder applications | Recommended when the current range extends toward 800A–1500A or when the drawing matches this structure. |
| LZZBJ9-10X | Legacy 10kV/12kV class replacement or related catalogue reference | Best handled as a related model rather than a separate SEO page if the structure and application overlap. |
Dimensions
| Item | Catalogue Reference | Engineering Note |
|---|---|---|
| Overall width | Approx. 290mm reference | Final value depends on variant and drawing. |
| Body height | Approx. 220mm reference | Used for cabinet clearance and installation layout check. |
| Mounting plate | Base plate with four mounting holes | Hole position must be confirmed before panel drilling. |
| Primary terminals | Top-side P1 / P2 terminal arrangement | Confirm busbar size, bolt hole and phase clearance. |
| Secondary terminals | Front lower terminal block | Confirm wiring access and sealing cover requirement. |
Terminals
The primary terminals are usually marked P1 and P2. The secondary terminals are marked according to the winding configuration, such as 1S1 / 1S2, 2S1 / 2S2 and other terminal groups if multiple secondary windings are supplied. Metering, protection and monitoring circuits must be wired according to the approved terminal diagram.
| Terminal | Function | Application Note |
|---|---|---|
| P1 / P2 | Primary terminals | Used for primary current direction and polarity reference. |
| 1S1 / 1S2 | First secondary winding | Usually used for metering or measurement output. |
| 2S1 / 2S2 | Second secondary winding | Usually used for protection relay output. |
| Grounding point | Protective grounding | One point of the secondary circuit should be grounded according to project practice. |
Service Conditions
- Installation location: indoor medium-voltage switchgear
- Rated voltage: 10kV, 11kV and 12kV class systems by project confirmation
- Rated frequency: 50Hz or 60Hz
- Ambient temperature: -5°C to +40°C for 12Q catalogue reference; -5°C to +55°C for related 10X reference
- Indoor environment should be free from conductive dust, corrosive gas, explosive medium and abnormal condensation.
- For high humidity, coastal, high altitude or heavy pollution projects, creepage distance and insulation coordination should be confirmed before ordering.
Standards and Compliance
The LZZB(J)6-12Q / LZZJB6-12Q series should be specified according to IEC 61869-2 and GB20840.2-2014 for current transformers. Some legacy catalogue data may also reference GB1208-2006 and IEC60044-1:2003. For new international product pages, IEC 61869-2 wording is recommended, while older standards can be listed as legacy reference when required by customer documentation.
Installation and Dimensions
This product is intended for indoor switchgear installation. Before cabinet production, the mounting hole position, primary busbar arrangement, secondary terminal direction, phase-to-ground clearance, wiring access and maintenance space should be confirmed with the approved outline drawing. Because the series includes several related model names, the final drawing must match the exact nameplate model and current ratio.
Safety Notes
- Confirm voltage class, insulation level, current ratio, secondary current, accuracy class and rated output before production.
- Check primary terminal spacing, busbar clearance, mounting holes and secondary wiring access before switchgear assembly.
- Connect primary and secondary terminals according to polarity marks and approved wiring diagram.
- 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 grounded according to project electrical safety requirements.
- Installation and commissioning shall be performed by qualified medium-voltage electrical personnel.
Ordering Info
- Product model: LZZB(J)6-12Q / LZZJB6-12Q
- Related model reference if required: LZZB6-12Q, LZZBJ6-12Q, LZZBJ9-10X
- Voltage class: 10kV, 11kV or 12kV class
- Rated primary current and rated secondary current: 5A or 1A
- Accuracy class and rated output for each secondary winding
- Protection class requirement: 5P10, 5P15, 10P10, 10P15 or project-specific requirement
- Rated short-time thermal current and rated dynamic current
- Mounting drawing, terminal direction and switchgear layout
- Applicable standard, routine test report and certificate requirements
- Quantity, label language, packaging and project documentation requirements
Selection Guide
- Use one main page name: Use LZZB(J)6-12Q as the main website model and include LZZJB6-12Q as a related variant.
- Confirm voltage class: Use 12kV class wording for international projects, with 10kV and 11kV compatibility stated by project confirmation.
- Select current ratio: Choose the primary current according to feeder load, metering range and protection settings.
- Select secondary current: Use 5A for conventional systems and 1A where lower burden or longer wiring is required.
- Choose core function: Use 0.2 / 0.2S / 0.5 / 0.5S for metering and 5P / 10P classes for protection.
- Verify withstand rating: Check short-time thermal current and dynamic current against the switchgear fault level.
- Approve drawings: Confirm outline dimensions, primary terminal layout, secondary terminals and mounting holes before production.