HWV -

HWV

Type HWV externally-mounted vacuum OLTC is a new vacuum tap changer developed by Huaming. It is composed of diverter switch, tap selector, oil tank and motor drive unit. The diverter switch and tap selector of HWV is consolidated in one oil chamber. iT is suitable for power and industrial transformers of Star or Delta connection. Its highest equipment voltage is 40.5 and 72.5kV; its three phases current is less than 1000A and rated frequency is 50 or 60 Hz.

Item	Specification			HWVIII			HWVI
1	Max. rated through-current (A)			400	800	1000	400	800	1000
2	Rated frequency (Hz)			50 or 60
3	Connection			3 phases Y or D connection			1 phase for any selectable winding connection
4	Max. rated step voltage (V)			3300
5	Rated step capacity (kVA)			1200	2200	3200	1200	2200	3200
6	Short-circuit current test (kA)		Thermal (3s)	8	8	12	8	8	12
			Dynamic (Peak)	20	20	30	20	20	30
7	Max. Operating Positions	Without change-over selector		18
		With change-over selector		35
8	Insulation to ground (kV)	Highest voltage for equipment Um		17.5		40.5		72.5
		Rated separate source AC withstand voltage (kV/50Hz,1min)		50		85		140
		Rated lightning impulse withstand voltage (kV,1.2/50μs)		150		200		350
9	Internal Insulation Level			4 grades of B, C, D and DE according to insulation level
10	Mechanical life			Not less than 1,500,000 operations
11	Contact life			Not less than 600,000 operations
12	Oil compartment of diverter switch		Service pressure	0.03Mpa
			Leakage test	No leakage under 0.08Mpa for 24 hours
			Over pressure protection	Bursting cap busts at 300 ± 20%kPa
			Protection relay	Oil flow speed set at 1.0m/s ±10%
13	Motor drive unit			SHM-D or CMA7
14	Oil filter plant			ZXJY-1 / ZXJY-2 / ZXJY-3 according to requirement (Necessary when max. rated through current is 1000A and above or OLTC used for industrial applications)