LOAD BREAK SWITCHES (LBS)
A load break switch is a disconnect switch that has been designed to provide making or breaking of specified currents.
This is accomplished by addition of equipment that increases the operating speed of the disconnect switch blade and the addition of some type of equipment to alter the arcing phenomena and allow the safe interruption of the arc resulting when switching load currents.
Disconnect switches can be supplied with equipment to provide a limited load switching capability. Arcing horns, whips, and spring actuators are typical at lower voltages.
These switches are used to de-energize or energize a circuit that possesses some limited amount of magnetic or capacitive current such as transformer exciting current or line charging currents. An air switch can be modified to include a series interrupter (typically vacuum of SF6 for higher voltage and current interrupting levels.
These interrupters increase the load break capability of the disconnect switch and can be applied for switching load or fault currents of the associated equipment.
Vacuum interrupters for Load Break Switches
| Rated Voltage |
Rated lightning impulse voltage |
Power frequency withstand voltage |
Rated Current |
Short circuit breaking current |
VI Type
(Dia.-Style) |
| kV |
kV |
kV |
A |
kApeak |
|
| 12/15.5 |
95 |
35 |
630 |
40 |
M01QC
(φ60-A) |
| 24/27 |
125 |
60 |
630 |
40 |
M02QC
(φ65-B) |
| 36/38 |
150 |
70 |
630 |
40 |
M03QC
(φ65-B) |
