Indoor Circuit Breakers

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35kV Polymer Load Break Fuse Cutout

24kV Silicon Rubber Load Break Fuse Cutout with Arc Chute

24kV 100A Load Break Fuse Cutout with Arc Chute

15kV Double column Polymer Fuse Cutout

24kV Polymer T Bar Type Fuse Cutout

24kV Silicon Rubber T Bar Type Fuse Cutout

24kV 100A Polymer Dropout Fuse

38KV 100A Polymer Dropout Fuse

Next-Gen Indoor High Voltage Vacuum AC Breaker

Model VF(R)-12

VF(R)-12 indoor embedded high-voltage alternating-current vacuum load switch-fuse combination (“vacuum load switch" )is a new generation vacuum switching equipment developed based on unique design ideas to meet the market demand. It is widely used for indoor armored air-insulated switch cabinets. In normal conditions, it can operate within its technical parameters in any grid of the specified voltage level safely and stably.

product details

Product Introduction

Product Parameter (Specification)

Item		Unit	Reference value
Item		Unit	VF-12/T630-20 Vacuum load switch	VFR-12/T125-50 Vacuum load switch-fuse combination	VFH-12/T630-25 High breaking capacity vacuum switch	VFHR-12/T125-50 High breaking capacity vacuum switch-fuse combination
Rated voltage		kV	12	12	12	12
Rated insulation level	Lightning impuse withstand voltage	kV	75	75	75	75
Rated insulation level	1min power-frequency withstand voltage	kV	42	42	42	42
Rated frequency		Hz	50/60	50/60	50/60	50/60
Rated current		A	630	125(fuse)	630	125(fuse)
Rated short-circuit breaking current		kA	-	50(fuse)	25	25
Rated short- circuit making current (peak value)		kA	50	-	63	-
Rated short-time withstand current		kA	20	-	25	-
Rated withstand current (peak value)		kA	50	-	63	-
Rated breaking current of cable during charge		A	16	-	-	-
Rated breaking current of no-load transformer		kVA	1250	-	1250	-
Rated breaking take-over current		A	-	3150	-	3150
Breaking times of the rated short-circuit current		Times
Mechanical life			M2 level	M2 level	M2 level	M2 level
Weight		kg	125

Transformer capacity and fuse selection

1.The fuse can cut off a large short-circuit current in less than 10 ms and its breaking current can be up to 50KA. Thus, it can protect the transformer most efectively.

2.In terms of match between the transformer and the fuse (Table 1), the potential surge current of the fuse must be considered. Thus, fusing current of the fuse must be 1.6 times of the rated value; designer must consider possible fluctuations of other parameters of the grid and reserve margins for them. If a fuse is selected for high-voltage motor protection, designer must consider frequency of start of the high-voltage motor because frequent starts of the high-voltage motor will result in the fuse's failure when timely cooling is not available.

Fuse selection

Primary voltage of the transformer(kV)	Capacity of the transformer(kVA)	Model of the fuse		Rated current of the fuse(A)
		Model for the domestic market	Model for international market
6.6	200	XRNT-10	12kV BDGHC	31.5
	250			40
	300/315			50
	400		12kV BDGHC	63
	500			80
	630			90