FZB21-12D/T630-20 Indoor High Voltage Vacuum Load SwitchDetailed product description：

FZB21-12D/T630-20 indoor high-voltage vacuum load switch (hereinafter referred to as load switch) is a three-phase AC 50Hz household device. In the rated voltage 12KV power system, it serves as the protection and control of electrical facilities, used for breaking and closing load currents, closed-loop currents, and carrying overload currents. It can also open and close no-load long lines, no-load transformers, and capacitors.
Install a grounding switch with the ability to close short-circuit currents.
The operating mechanism can be manually or electrically operated, facilitating the remote control requirements of the power system.

The FZRN21-12D/T125-31.5 indoor high-voltage vacuum load switch fuse combination device (hereinafter referred to as the combination device) is composed of a load switch and a fuse. In addition to the function of a load switch, it also has a short-circuit protection function.
In the Chinese market, load switches have gradually replaced circuit breakers and have been widely used. Compared with circuit breakers, load switches are not only cheaper and easier to operate, but also have faster fault response when equipped with fuses, which is particularly effective in protecting transformers. Load switches have been favored by urban and rural users and are increasingly valued and welcomed by people.
2. Normal usage conditions
a) Surrounding air temperature: upper limit+40oC, lower limit -40oC;
b) Relative humidity: daily average not exceeding 95%, monthly average not exceeding 90%;
c) Water vapor pressure: daily average not exceeding 2.2kPa, monthly average not exceeding 1.8kPa;
d) A place without fire, explosion hazard, serious pollution, chemical corrosion, and severe vibration.

3 Main Technical Parameters
3.1 Main technical parameters of load switch

serial number	parameter name		unit	data
one	rated voltage		kV	twelve
two	rated frequency		Hz	fifty
three	rated current		A	six hundred and thirty
four	Rated Active load breaking current			six hundred and thirty
five	Rated closed-loop breaking current			six hundred and thirty
six	5% rated active load breaking current			thirty-one point five
seven	Rated cable charging breaking current			ten
eight	Rated no-load transformer capacity		kVA	one thousand two hundred and fifty
nine	1-minute power frequency withstand voltage	Vacuum fracture, phase to phase, relative to ground	kV	forty-two
		isolation gap		forty-eight
ten	Lightning impulse withstand voltage (peak value)	Vacuum fracture, phase to phase, relative to ground		seventy-five
		isolation gap		eighty-five
eleven	4S rated short-time withstand current (thermal stability)		kA	twenty
twelve	Rated peak withstand current (dynamic stability)		kA	fifty
thirteen	Rated short-circuit closing current (peak)			fifty
fourteen	Rated current breaking times		time	ten thousand
fifteen	mechanical life			ten thousand
sixteen	Allowable wear thickness of vacuum arc extinguishing chamber contacts		mm	two
seventeen	Manual operating torque		N.m	≤200

3.2 Technical parameters of composite electrical appliances

serial number	parameter name		unit	data
one	rated voltage		kV	twelve
two	rated frequency		Hz	fifty
three	Maximum rated current of fuse		A	one hundred and twenty-five
four	Rated breaking AC current			three thousand one hundred and fifty
five	The opening time of the switch triggered by the fuse		ms	40±5
six	Rated short-circuit breaking current (effective value)		kA	thirty-one point five
seven	Rated short-circuit breaking current (peak)		kA	fifty
eight	1-minute power frequency withstand voltage	Vacuum fracture, phase to phase, relative to ground	kV	forty-two
nine		isolation gap		forty-eight
	Lightning impulse withstand voltage (peak value)	Vacuum fracture, phase to phase, relative to ground		seventy-five
ten		isolation gap		eighty-five
	Fuse impactor output energy		J	2-5

3.3 Mechanical adjustment parameters

serial number	parameter name	unit	data
one	Contact opening distance/overtravel	mm	10±1/4±0.5
two	Average closing speed/average opening speed (contact just opened 6mm)	m/s	0.6±0.2/1.1±0.2
three	Synchronization of three-phase contact opening and closing/contact closing bounce time	ms	≤2/≤2
four	Distance between charged bodies and air to ground	mm	≥125
five	Main circuit resistance of upper and lower brackets	μΩ	≤70

4. FZB21-12D/T630-20 Indoor High Voltage Vacuum Load Switch Appearance and Installation Dimensions

FZB21-12D/T630-20 Indoor High Voltage Vacuum Load Switch