Vacuum Interrupters

BF-40.5/1250-12.5 Vacuum interrupter
Rated parameters of vacuum interrupter

№	Parameter item	Unit	Value
1	Rated voltage	kV	40.5
2	Rated power-frequency withstanding voltage	kV	95 ①
3	Rated lighting impulses withstanding voltage	kV	185 ①
4	Rated frequency	Hz	50
5	Rated current	A	1250
6	Rated peak withstanding current	kA	31.5
7	Rated short-time withstanding current	kA	12.5
8	Rated duration of short-circuit	S	4
9	Rated short-circuit making current	kA	31.5
10	Rated active power load breaking current	A	1250
11	Rated closed-loop breaking current	A	1250
12	Rated cable charging breaking current	A	10
13	Mechanical life	Times	10000
Note:①Value in transformer oil or equivalent insulation equipment

Mechanical parameters of vacuum interrupter:

№	Parameter item	Unit	Value
1	Rated contact gap	Mm	16±1
2	Contact closing force due to bellows and atmosphere	N	120±50
3	Counterforce of contact	N	200±50
4	Circuit resistance at low limit of rated contact force	μΩ	≤40
5	Contact erosion permission length	Mm	3
6	Moving part weight	Kg	1.4

Mechanical parameters of vacuum load switch equipped with vacuum interrupters

№	Parameter item	Unit	Value
1	Average breaking speed	m/s	1.6±0.2
2	Average closing speed	m/s	1.0±0.2
3	Rated operation pressure of contact	N	550
4	Bounce duration of contact closing	Ms	≤2
5	Rebound amplitude of breaking contact	Mm	Undetermined
6	Out of simultaneity of contact closing and opening	Ms	≤1