Pressure monitoring device and pressure monitoring method for vacuum valve

A vacuum valve pressure monitoring device which is disposed in a multiple-phase vacuum breaker including:

• a main circuit opening/closing part including, on a per-phase basis, a vacuum valve and an insulating frame covering the vacuum valve;
• and an operation mechanism part for opening/closing a contact of the vacuum valve, the pressure monitoring device comprising:
• a first electrode for each phase disposed on one side surface of the insulating frame for each phase and grounded via an impedance;
• a second electrode disposed between the adjacent insulating frames and grounded via a switch;
• and
• a potential measuring device for each phase connected in between the impedance and the first electrode.

A method for monitoring vacuum valve pressure of a vacuum breaker including:

• a main circuit opening/closing part including a vacuum valve and an insulating frame covering the vacuum valve;
• and an operation mechanism part for opening/closing a contact of the vacuum valve,
• wherein the method is to monitor the degradation of internal pressure of the vacuum valve by taking measurement of a potential between two electrodes in a state where a switch is turned on,
• the two electrodes including:
• a first electrode disposed on one side surface of the insulating frame and grounded via an impedance;
• and
• a second electrode disposed on another side surface of the insulating frame and grounded via the switch.

A method for monitoring vacuum valve pressure of a multiple-phase vacuum breaker including:

• a main circuit opening/closing part including, on a per-phase basis, a vacuum valve and an insulating frame covering the vacuum valve;
• and an operation mechanism part for opening/closing a contact of the vacuum valve,
• wherein the method is to monitor, on a per-phase basis, the degradation of internal pressure of the vacuum valve by taking measurement of a potential between two electrodes in a state where a switch is turned on,
• the two electrodes including a first electrode which is disposed on one side surface of the insulating frame for each phase and grounded via an impedance, and
• a second electrode which is disposed between the adjacent insulating frames and grounded via the switch.