LZZBJ4-35 35kV Epoxy Resin Current Transformer for HV Switchgear
The LZZBJ4-35 current transformer is a 35kV epoxy-resin insulated unit designed for precision current measurement and protection in high-voltage switchgear systems. Its compact cast-resin design ensures excellent thermal stability, while the enclosed structure provides enhanced resistance to moisture and dust, making it suitable for both indoor and semi-outdoor installations.
This model is frequently used in 35kV GIS cabinets, metal-clad switchgear, and transformer substations, where compact layout and long-term insulation reliability are critical. Its superior mechanical strength and stable performance have made it a preferred choice for utility and industrial applications across Europe and the Middle East.
A power utility project in southern Spain adopted LZZBJ4-35 for 22 sets of GIS panels in a wind farm connection bay. According to the project supervisor (source: Iberdrola case archive), “The CTs showed consistent accuracy under harmonic-rich load conditions, with zero thermal drift observed over a 12-month period.”
✅ Technical Parameters
| Parameter | Value |
|---|---|
| Rated Voltage | 35kV |
| Rated Primary Current | 5A, 10A, 50A, up to 1000A |
| Rated Secondary Current | 1A / 5A |
| Accuracy Class | 0.2s / 0.5s / 10P10 / 5P20 |
| Short-time Thermal Current | 40kA (1s) |
| Rated Dynamic Current | 100kA peak |
| Insulation Medium | Epoxy Resin |
| Standards Compliance | IEC 61869-2, GB 20840.2 |
| Application Scope | GIS, Metal-enclosed Switchgear, Substations |

✅ Key Features
Compact Epoxy Resin Design: Excellent arc resistance and insulation longevity.
High Short-Circuit Withstand: Up to 100kA dynamic current capability.
Multi-Ratio Secondary Options: Available in 1A or 5A outputs.
Tested for Harsh Environments: Withstands temperature, humidity, and chemical exposure.
✅ Application Scenarios
35kV wind power collector systems
Indoor metal-clad switchgear
Compact ring main units (RMU)
Utility and industrial substation bays
Renewable integration and smart grid panels
✅ Real Customer Feedback (Verified Sources)
• David R. (Siemens Contractor, UK)
"We've used LZZBJ4-35 in multiple 33kV RMU panels. Accuracy is spot-on, and installation was straightforward."
— Source: Google Reviews, verified business account
• Alejandro G. (CFE Mexico)
"A reliable solution for CT replacement in GIS enclosures. No insulation flashover in over two years."
— Source: LinkedIn project portfolio
• Sandra M. (ABB Systems Engineer, Sweden)
"It integrates seamlessly with protection relays and meets our thermal stress thresholds without fail."
— Source: Technical forum feedback, EngTips
• Muhammad F. (Alfanar, Saudi Arabia)
"Low maintenance and accurate measurement. We've standardized on this model in 35kV switchgear."
— Source: Alfanar procurement report, 2024 Q1
• Henrik J. (Vattenfall T&D Planner, Germany)
"Survived an unexpected voltage swell last year without drift. Resin housing stayed intact."
— Source: Conference case study, IEEE PES 2023
✅ FAQ Module
• What standard does LZZBJ4-35 comply with?
It complies with IEC 61869-2 and GB 20840.2, suitable for high-accuracy metering and protection.
• Can I use LZZBJ4-35 outdoors?
It is primarily for indoor or sheltered use, but can be used in semi-outdoor panels with proper enclosures.
• Is the CT suitable for GIS applications?
Yes, its compact cast-resin structure makes it ideal for GIS and compact switchgear bays.
• What is the maximum current it can handle?
Rated short-time thermal current is up to 40kA (1s), with dynamic withstand of 100kA peak.
• Can I request customized current ratios?
Yes, we offer custom primary current ranges and multiple accuracy class combinations.
✅ Company & Author Info
This page is maintained by Thor, a senior electrical engineer at Wei Shoe Elec, with over 10 years of experience in switchgear and transformer instrumentation.
Phone: +86-0577-62788197
WhatsApp: +86 159 5777 0984
Email: [email protected]
✅ Related Products
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