Product Overview
Split-Core Zero-Sequence Current Transformer from Subian Electric’s Xuzhou Factory
The LXK opening and closing zero-sequence current transformer is a specialised piece of equipment used for high-voltage power systems. It measures zero-sequence current for ground-fault protection. The split-core construction of the device makes it easy to install around existing cables and circuits without any dismantling. It is a great help when retrofitting the power system and upgrading substations or OEM protection panels.
Applications & circuit protection
The LXK zero-sequence CT is utilized in neutral-earthing and protective schemes that need fast detection of a fault occurring on the ground and passing it on to the protective relays.
- Protection of substations: Create a circuit to detect earth faults on feeders and transformers.
- Distribution networks: Monitor the zero-sequence form at medium voltage systems.
- Retrofit projects: Split core helps retrofit existing cables.
- OEM panels: Combination with the relay and other equipment for monitoring.
Construction & operating reliability
The opening/closing concept makes it easy for workers to padlock the CT around any live cable or a pre-existing cable, and the toroidal core offers the continuous zero-sequence measurement that’s necessary for protection relays.
- The split-core opening design allows easy efficient retro-fitting in the field.
- The use of the toroidal core with high permeability allows for sensitive fault detection.
- The accuracy class of 5P/10P matches the protection relay application.
- The compact housing comes with a clearly marked terminal.
- It can be used in indoor applications and in watertight outdoor cabinets.
Technical Parameter
| Parameter | Value |
| Rated voltage | 10 kV / 35 kV class |
| Rated zero-sequence current | 100 A / 200 A / 500 A |
| Accuracy class | 5P / 10P |
| Rated burden | 10 / 15 / 20 VA |
| Rated frequency | 50/60 Hz |
| Construction | Opening and closing (split-core) |
| Application | Zero-sequence / ground-fault protection |
Current Transformer Price & Factory Quote
The price of CT is dependent on parameters such as ratio, accuracy of the class, burden, insulation and quantity. The price quoted her is Zero-Sequence Current Transformer from factory price list and made available for wholesale order by the panel manufacturers and distributors.
- The standard ratios are quoted from the price list.
- The multi-ratio and custom accuracy is quoted as per order.
- Container charges are available.
CT Wiring & Secondary Connection
Zero Sequencing Current Transformer comes with distinct primary and secondary marking. Connect the meter or relay in proper polarity in the secondary circuit, and never leave the secondary open when energised.
- Markings according to the standard practice.
- Marking of polarity for the right connection.
- Shorting certificates upon request.
Compare CT Options
Choose the instrument transformer that fits your scheme:
| Feature | This CT | Alternative |
| Ratio | As specified | Other ratios available |
| Accuracy | Per class | 0.2 / 0.5 / protection class |
| Insulation | Epoxy cast / oil | Indoor or outdoor design |
| Application | Metering / protection | Multi-ratio or special duty |
Export Markets & Country Compatibility
Instrument transformers can be sent to switchgear manufacturers and dealers from across the world and are made up according to their respective accuracy and ratio together with the specifications of each of the target markets.
CT Dimensions, Weight & Packing
Size and weight of conveyance are dependent on ratio, insulation and fixing method. Units have been made compact for panel or cable construction, with terminals being hosed against damage. Dimension drawings are supplied in the technical documentation.
- Panel mounting dimensions are compact.
- Terminals are protected during shipping.
- Size drawings to suit every model.
Standards & certifications
The design of the LXK zero-sequence current transformer adheres to IEC 60044-1 / IEC 61869 methodology. Test reports and documentation can be provided in accordance with the requirements of projects and the market.
- Standardized design: IEC 60044-1 / IEC 61869 series.
- Accuracy: class 5P/10P.
- Marking of terminal and polarity according to standard.
- Designed for use in HV protection and monitoring schemes.
OEM & B2B supply support
Having extensive experience in the production of high-quality power devices, Subian Electric manufactures and distributes zero-sequence CTs to integrators of protective systems, distributors, and contractors working at substations ensuring you have access to technical data and samples.
The fittings can be made to your different specifications in terms of rated currents, the inner diameter, and burden by sending us the details about your peculiar application or tender.
- We also provide samples for testing the solution.
- We can supply the equipment in required quantities.
- We offer OEM / ODM assistance to users of protection devices.
- We can customize our products marking and packaging.
- We provide guidance with necessary documentation and certification.
Frequently Asked Questions
What is a zero-sequence current transformer?
It measures the cumulative sum of three current phases and observes zero-sequence current, which occurs as a result of short circuiting. The data is transferred to protective relays.
Why choose the opening and closing type?
The split-core type helps to fasten the device on a cable without breaking the current.
What accuracy class is used?
LXK zero-sequence CTs are usually manufactured in 5P or 10P accuracy class that meet the demand of protection relays.
Can I get samples for testing?
Yes, samples are available. Please specify cable diameter, rated current, burden, and market destination, and we will confirm the technical specifications.
