GEDQ-ZCB-110 Outdoor Neutral Point Isolator Switch

The GEDQ-ZCB-110 is a high-voltage outdoor Isolator switch designed specifically for neutral point isolation in 110kV substations or transmission lines. It provides safe, visible separation for relay protection testing, grounding operations, or transformer neutral disconnection during scheduled maintenance or emergency switching.

With a durable porcelain or polymer insulator and available with manual or motorized operation, this switch ensures mechanical reliability and arc-free breaking under no-load conditions.

🔧 Key Features

Model: GEDQ-ZCB-110
Voltage Rating: 110kV
Current Rating: 630A / 1250A
Installation: Outdoor, single-phase or three-phase
Function: Neutral point isolator, visible break
Actuation: Manual lever or motorized control
Standards: IEC 62271-102, GB/T 1985

⚙️ Technical Specifications

Parameter	Value
Rated Voltage	110kV
Rated Current	630A / 1250A
Power Frequency Withstand	230kV (1 min)
Lightning Impulse Withstand	≥550kV
Rated Short-Time Withstand	25kA / 3s
Mechanical Endurance	≥2000 operations
Insulator Material	Porcelain or Composite Polymer
Altitude	≤3000m
Ambient Temperature	–40°C to +50°C

🏭 Specialized Application Scenarios

The GEDQ-ZCB-110 switch is built for scenarios that demand reliable neutral point management, which sets it apart from typical phase-line isolators:

✅ Transformer Neutral Disconnection

Used to isolate the neutral of power transformers during maintenance, protective testing, or transitioning to grounding resistors.

✅ Line-End Grounding & Potential Control

Installed at long overhead transmission line ends to manage capacitive voltage buildup and allow safe grounding.

✅ Neutral Point Relay Protection

Essential in substations where zero-sequence voltage measurement and differential protection rely on precise isolation points.

🧱 Construction Overview

Double Break Design: Ensures full isolation and safety margin
Insulation Rods: Glass-fiber reinforced pull rods with weatherproof coating
Motor Drive Unit (Optional): For remote SCADA integration and automation
Earth Switch Add-On: Optional grounding knife for fast discharge
Corrosion-Resistant Hardware: Stainless steel fittings and galvanized brackets

❓ Frequently Asked Questions

• Why is a neutral point isolator needed in 110kV systems?
To safely disconnect the transformer or line neutrals during relay testing, or to prevent unwanted ground return currents.

• Is it suitable for remote operation?
Yes. The motorized version supports remote control and interlocking logic in automated substations.

• What’s the difference from a phase Isolator switch?
This is not for load-carrying lines—it’s only for neutral line segments under no-load or capacitive conditions.

• Can it be combined with a grounding knife?
Yes. Many configurations include a double-break switch with an integrated earth switch for safety.

• How is the visible break achieved?
The break contacts are mounted above the insulators with clearly visible air gaps once operated.