Description

JN17-12/40 Grounding Switch Introduction

The JN17-12/40 is a high-voltage grounding switch designed for use in 12kV power distribution systems. Its primary functions include:

1. Safety Grounding – Provides reliable earthing for de-energized circuits during maintenance, protecting personnel from accidental energization or residual charges.

2. Isolation Verification – Works in conjunction with circuit breakers/disconnectors to visibly confirm electrical isolation before maintenance.

3. Fault Protection – Some models may short-circuit fault currents (40kA rated) when used with fault-making capability, aiding system protection.

4. System Compatibility – Typically installed in switchgear, ring main units, or substations as a visible grounding point.

Key features often include:

• 12kV rated voltage / 40kA short-circuit withstand capacity

• Manual or motorized operation options

• Mechanical interlocking with other switching devices to prevent misoperation

This device complies with IEC/GIS standards for medium-voltage equipment, ensuring operational safety in power grids.

Technical Parameter

No.	Item	Unit	Data
1	Rated voltage	KV	12
2	Rated short time withstand current	KA	40
3	Rated short circuit withstand time	S	4
4	Rated short circuit making current	KA	80
5	Rated peak withstand current	KA	80
6	Rated insulation level	1min power frequency withstand voltage	42
7		Lightning impulse withstand voltage	75
	Mechanical life		2000

 

(Unit: mm)

Specification	E	F	G	H	D
JN17-12/40-210	210	50	185	655	516
JN17-12/40-220	220	50	185	675	536
JN17-12/40-230	230	50	185	695	556
JN17-12/40-250	250	50	185	735	596
JN17-12/40-275	275	50	210	810	646

The JN17-12/40 grounding switch is widely used in medium-voltage (12kV) power distribution systems and is commonly installed in the following types of switchgear:

1. Metal-Enclosed Switchgear (Indoor/Outdoor)

• Used in KYN, XGN, or other fixed/movable switchgear panels to provide a visible grounding point for maintenance safety.

• Often integrated with circuit breakers and disconnectors to ensure proper isolation before grounding.

2. Ring Main Units (RMUs)

• Installed in SF₆-insulated or air-insulated RMUs for cable grounding during feeder maintenance.

• Ensuresafe operation in urban distribution networks and underground cable systems.

3. Compact Substations & Prefabricated Switchgear

• Used in box-type substations (e.g., Euro-style compact substations) to provide a reliable grounding solution for transformers and cables.

4. Wind/Solar Power Systems

• Applied in renewable energy switchgear to ground circuits during turbine or PV system maintenance.

5. Railway & Industrial Power Systems

• Installed in traction power supply units and industrial switchgear for safe maintenance of high-voltage equipment.

Key Compatibility Features:

✔ Interlocking Mechanism – Prevents closing on live circuits (when paired with disconnectors).
✔ Motorized/Manual Operation – Adaptable to automated or manual switchgear systems.
✔ 40kA Fault Withstand – Suitable for high short-circuit current applications.

This grounding switch ensures compliance with IEC 62271 standards for medium-voltage switchgear safety.