Abstract: An apparatus for improving the service life of a submersible probe residing in a tank includes a liquid level detector adapted to detect when a liquid in the tank rises to a first level. The first level is above the probe. A controller is coupled to the liquid level detector. The controller is configured to increase at least one of a voltage and a current applied to the probe responsive to the liquid being detected at the first level. The controller is configured to reduce an electrical potential field produced by the probe responsive to the liquid falling below a second level, thereby extending the service life of the probe by reducing the accumulation of foreign matter on the probe when the pump is not activated.

Abstract: An apparatus for improving the service life of a submersible probe residing in a tank includes a liquid level detector adapted to detect when a liquid in the tank rises to a first level. The first level is above the probe. A controller is coupled to the liquid level detector. The controller is configured to increase at least one of a voltage and a current applied to the probe responsive to the liquid being detected at the first level. The controller is configured to reduce an electrical potential field produced by the probe responsive to the liquid falling below a second level, thereby extending the service life of the probe by reducing the accumulation of foreign matter on the probe when the pump is not activated.

Abstract: A probe is mounted on a water submersible pump or other fluid handling device housed within a vault for a transformer, elevator or the like. The probe will extend into any water which accumulates in the bottom of the vault enabling a conductive path to be established through an appropriate electric circuit to the pump motor to permit operation of the pump for pumping water from the vault. Oily fluids, which are immiscible in the water and will normally rise to a level above the water level in the vault, will come in contact with the probe to render the probe nonconductive, thereby inactivating the pump circuit. An alarm is provided to indicate the presence of oil in the vault. In order to prevent false alarms when the probe is nonconductive due to immersion in air, a controller is provided to inhibit operation of the alarm unless a float is raised and the probe is nonconductive.

Abstract: A probe is mounted on a water submersible pump housed within a transformer vault. The probe will extend into any water which accumulates in the bottom of the transformer vault enabling a conductive path to be established through an appropriate electric circuit to the pump motor to permit operation of the pump so that the water which is on the bottom of the vault can be safely pumped from the vault. As the water level falls as it is pumped, oily fluids, which are immiscible in the water and will normally rise to a level above the water level in the vault, will come in contact with the probe to form an electrical insulator to inactivate the circuit to disconnect a power source from the pump motor.

Abstract: A probe is mounted on a water submersible pump housed within a transformer vault. The probe will extend into any water which accumulates in the bottom of the transformer vault enabling a conductive path to be established through an appropriate electric circuit to the pump motor to permit operation of the pump so that the water which is on the bottom of the vault can be safely pumped from the vault. As the water level falls as it is pumped, oily fluids, which are immiscible in the water and will normally rise to a level above the water level in the vault, will come in contact with the probe to form an electrical insulator to inactivate the circuit to disconnect a power source from the pump motor.