3 Pole Withdrawable Type Vacuum Interrupter

Basic Info

Model NO.	VD4
Breaking Capacity	High Voltage Circuit Breakers
Operation	Electric Type
Speed	Normal Type Circuit Breaker
Arc-extinguishing Medium	Vacuum
Installation	Fixed/Drawable
Structure	Vcb
Poles Number	3
Type	Circuit Breaker
Function	Conventional Circuit Breaker, Circuit-Breaker Failure Protection, Overcurrent Protection
Certification	ISO9001-2000
Transport Package	Carton
Specification	IEC, GB
Trademark	Rockwill
Origin	China
HS Code	8535210000
Production Capacity	1000PCS

Product Description

Withdrawable circuit-breakers

Description

VD4 series medium voltage vacuum circuit-breakers with lateral operating mechanism feature the separate pole construction technique.The operating mechanism is the EL trip-free stored energy type with independent opening and closing regardless of the operator's action. The EL operating mechanism is widely used in all VD4 series circuit-breakers with frontal control.The circuit-breaker can be remote controlled when fitted with dedicated electrical accessories (gearmotor, opening and closing release).The operating mechanism, the three poles and the current sensors (if installed) are assembled on a metal frame without wheels. The construction is extremely compact, strongly built and low in weight. VD4 series circuit-breakers with lateral operating mechanisms are life-long sealed pressure devices (Standards IEC 62271-100 and CEI EN 62271-100). Additionally, VD4 series circuit-breakers have been type tested for low temperature and marine applications (Germanischer Lloyd).VD4 vacuum circuit breakers have been designed for indoor use and air insulated switchboards.
Advantages

Vacuum circuit-breakers have particular advantages for use in networks where there is a high switching frequency in the working current range and/ or where a certain number of short- circuit breaking operations are expected. VD4 vacuum circuit- breakers are suitable for auto reclosing and have exceptionally high operating reliability and long life. The circuit- breakers are notable for their compact design, small dimensions together with high capacity. The operating mechanisms have a low maintenance requirement and the interrupters are maintenance- free throughout their service lives. They are well suited to all load breaking operations which occur in practice, and in particular:

• Short-circuit currents;
• Overhead lines under load and, no-load conditions;
• Cables under load and no-load conditions;
• Transformers under load and no-load conditions;
• Generators under load and no-load conditions;
• Ripple control system;
• Capacitor banks(also parallel switching) and Motors with starting currents above 600A;

Fields of application

Below is the list of SM6 range units used in MV/LV transformer substations and industrial distribution substations:

• Cable control and protection
• Overhead control and protection
• Transformers and distribution substations
• Motor and transformer control and protection
• Generator control and protection
• Capacitor bank control and protection

Diagrammatic sketch

Circuit-breaker operating mechanism

A Open/closed auxiliary contactsB Geared motor for closing spring chargingC Built-in closing spring charging leverD Mechanical signalling device for circuit-breaker open/closedE Mechanical operation counterF Plug-socket connectors of electrical accessories in the truckG Signalling device for closing springs charged/discharged

H Service releasesI Closing pushbuttonL Opening pushbuttonM Operating mechanism locking electromagnetN Additional shunt opening releaseO Transient contactP Contacts for signalling spring charged/discharged

Main characteristics

Circuit-breaker		VD4/W 36
Standards		IEC 62271-100
Rated voltage	Ur [kV]	36
Rated insulation voltage	Us [kV]	36
Withstand voltage at 50 Hz	Ud (1 min) [kV]	70
Impulse withstand voltage	Up [kV]	170
Rated frequency	fr [Hz]	50
Rated normal current	Ir [A]	630 / 1250 / 1600 / 2000 / 2500 / 3150
Rated breaking capacity (rated short-circuit breaking current symmetrical)	Isc [kA]	20 / 25 / 31.5 / 40
Rated short-time withstand current (3s)	Ik [kA]	20 / 25 / 31.5
Making capacity	Ip [kA]	50 / 63 / 80 / 100 / 125
Operation sequence		[O - 0.3 s - CO - 15 s - CO]
Opening time	[ms]	33 ~ 60
Arcing time	[ms]	10 ~ 15
Total breaking time	[ms]	43 ~ 75
Closing time	[ms]	30 ~ 60
Operating temperature	[ºC]	-5 ~ + 40