ZW8M-12 Outdoor High Voltage Permanent Magnet Vacuum Circuit Breaker

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Product Introduction

The ZW8M-12 outdoor permanent-magnet vacuum circuit breaker utilizes the vacuum arc extinguishing principle and a permanent-magnet operating mechanism, integrating microprocessor technology, modern communications technology, and new switch materials. This outdoor power distribution device is rated for 12kV, 50Hz, three-phase AC. It is widely suitable for use as a disconnect or tie switch in urban power grids, or as an outgoing line switch in outdoor substations in rural power distribution systems. It effectively performs the functions of a traditional recloser, disconnecting and closing load currents and interrupting short-circuit currents.

Main features

● Intelligent Control: This circuit breaker features local switch status control, three-stage overcurrent protection, and triple automatic reclosing. In addition, it features an RS-485 communication interface for telemetry, remote adjustment, remote control, and remote communication, making it suitable for automated power distribution systems of all sizes.
● Permanent Magnetic Operating Mechanism: This circuit breaker utilizes the most advanced permanent magnetic operating mechanism. Its components are wear-resistant and its mechanical lifespan reaches 30,000 cycles, three times that of a conventional spring mechanism. Because the permanent magnetic mechanism has 70% fewer mechanical parts than a spring mechanism, switch reliability is significantly improved.
● Fully Sealed Structural Design: The circuit breaker's vacuum interrupter, operating mechanism, and operating linkage are fully sealed within the breaker base, preventing condensation-induced corrosion of circuit breaker components. This product offers a maintenance-free lifespan of 10 years.

Main functions and effects

The core function of the ZW8M-12 is to serve as a protection and control unit for power systems. It is primarily installed on 10kV distribution lines. For example:

Control: Reliably connects and disconnects normal power flow according to grid operating needs (e.g., planned power outages and power transmission).

Protection: When a fault current (such as a short circuit or overload) occurs in the line, the circuit breaker automatically trips and disconnects the faulty circuit, protecting other equipment in the entire grid and preventing the accident from escalating.

Automatic reclosing: This is a critical function. Most faults on transmission lines (especially overhead lines), such as lightning strikes and wind-blown foreign objects, are transient and return to normal operation once the fault disappears. After tripping, the circuit breaker automatically recloses according to a pre-set sequence (e.g., "open → delay → reclose"). If the fault disappears, power is restored, significantly improving power supply reliability. If the fault is permanent, the circuit breaker is opened again and locked, preventing reclosing.

Product model and meaning

product-373-197

Operating environment conditions

1. Ambient temperature: -40°C to +40°C;
2. Altitude not exceeding 2000m. Requirements above 2000m are subject to negotiation with the user.
3. Wind pressure not exceeding 700Pa (equivalent to a wind speed of 34m/s).
4. Daily average relative humidity not exceeding 95%, monthly average not exceeding 90%.
5. Air pollution level III.
6. Ambient air should not be significantly contaminated by corrosive or flammable gases.
7. No frequent severe vibration.

Main technical parameters

No.		Unit	Data
Rated voltage		KV	12
1min power frequency withstand voltage	Phase-to-phase, phase-to-ground	KV	42
	Break		48
Lightning impulse withstand voltage	Phase-to-phase, phase-to-ground		75
	Break		85
Rated frequency		Hz	50
Rated short-circuit current breaking times		times	30
Secondary circuit 1-minute power frequency withstand voltage		kV	2
Rated current		A	630,1250
Rated short-circuit breaking current		KA	20
Rated short-circuit making current (peak value)			50
Rated short-time withstand current			20
Rated peak withstand current			50
Rated operating sequence			Open-0.3S-Close Open-180S Close Open
Rated operating voltage		V	～220
Overcurrent release operating current		A	5
Overcurrent release trip current accuracy		%	±10
Mechanical life		times	30000
Quality		KG	210

Mechanical characteristic parameter table

Name		Unit	Data
Contact span		mm	11±1
Contact travel		mm	3⁺¹_-0.3
Average opening speed		m/s	1.1±0.3
Average closing speed			0.7±0.15
Contact closing bounce time		ms	≤2
Three-phase opening asynchrony			≤2
Closing time			25~50
Opening time			15~50
Full-break time			≤100
Arc burning time			≤20
Conductive circuit resistance of each phase	Phase B	µΩ	≤150
	Phase A, C		≤350

Appearance and installation dimensions

product-772-410

ZW8M-12 outdoor permanent magnet vacuum circuit breaker

product-739-420

Controller dimensions

Ordering Instructions

1. Product model, name, quantity, rated voltage, and rated current.
2. Current transformer ratio.
3. Whether or not the device includes an isolating switch.
4. Spare parts required by the contract.

Please contact us at:

Email:pannie@hdswitchgear.com

Whatsapp/Wechat:+8618789455087