01
VTD5-(12/24)40.5 Vacuum Circuit Breaker for GIS
General
For vacuum circuit breakers with a rated current of 2000 A and above, a high-strength insulating plate holding the vacuum interrupter will be used, which is mounted on the flange plate. In contrast, for those with a rated current below 1600 A, an APG enclosed-type structure is adopted. This structure fixes the vacuum interrupter (VXG) onto the flange plate using a fixed plate.
The opening and closing operation is achieved through the connection of the vacuum interrupter's dynamic side to the insulating rod, and the stainless steel sealing bellows connecting the crank arm, rod, down crank arm, and mechanism. All secondary cables are connected to an aerial socket, which facilitates convenient secondary wiring.
Vacuum circuit breaker has the function that open, rated current and open circuit and close short circuit current.
Main technical parameters
|
Item |
Unit |
Parameter |
|||
|
Rated voltage |
kV |
12 |
24 |
40.5 |
|
|
Rated current |
A |
630, 1250, 1600, 2000, 2500, 3150 |
|||
|
Rated short-circuit breaking current |
kA |
20, 25, 31.5 |
|||
|
Rated insulation level |
1 min rated power frequency withstand voltage (r.m.s) |
kV |
42 |
65 |
95 |
| Rated lighting impulse withstand voltage (peak) |
kV |
75 |
125 |
85 |
|
|
Rated short-time withstand current (4s) |
kA |
20, 25, 31.5 |
|||
|
Rated peak short-time current |
kA |
50, 63, 80 |
|||
|
Rated short-circuit making current |
kA |
50, 63, 80 |
|||
|
Rated operating sequence |
/ |
O - 0.3s - CO - 180s - CO |
|||
|
Mechanical life |
Times |
10000 |
|||
Outline dimension and structure diagram(mm)


Maintenance
The vacuum circuit breaker should be subject to an annual power-off inspection and maintenance to ensure normal operation. The inspection should cover the following aspects:
a) Perform a power frequency withstand voltage test on the tube, measure the vacuum level, and record the results.
b) Conduct a power frequency withstand voltage test on the insulating components.
c) Test the breaker's contact gap, contact travel, and mechanical characteristics, and record the results.
d) Inspect the connecting bolts, nuts, and other adjustable parts of the connections for any signs of loosening, especially the small screws at the auxiliary switch lever and the locking nuts connected to the vacuum tube's moving conductor rod.
e) Check the retaining rings, pins, and other components at the rotating joints for any signs of loosening or disengagement; apply lubricating grease to the rotating and sliding parts.
f) For vacuum circuit breakers used with currents exceeding 1,600 A, perform a direct current (DC) resistance test on each pole and record the results.
g) If tube replacement is required, follow the instructions in the product manual. After replacement, conduct mechanical characteristic tests and withstand voltage tests.
h) After the annual inspection and before commissioning, perform 8 to 10 no-load operations to ensure everything is functioning normally before commissioning.

