PROTECTION DEVICE FOR SUBMERSIBLE PUMPING UNIT Russian patent published in 2008 - IPC F04B49/02 F04B47/00 

FIELD: oil refining industry.

SUBSTANCE: invention relates to device for protection of submersible pumping unit operating under conditions affecting serviceability of its systems. Proposed device contains submersible electric motor connected to three-phase power circuit with insulated neutral by means of power supply breaker with control unit, submersible electric motor supply transformer and power cable with shield. Cable insulation fault detector is coupled by actuating circuit with control unit and by input circuit, with neutral point of secondary winding of submersible electric motor supply transformer. Submersible device includes minimum one parameters pickup with output part connected to power circuit of submersible electric motor and to cable shield. Output part of submersible device is made in form of switch resistance-coupled between power supply cable of submersible electric motor and power cable shield. At preset tolerable parameters of pickup (pickups), switch has resistance higher than resistance of operation of insulation fault detector, and at conditions of deviation from preset tolerable parameter of pickup (pickups), it has resistance lower than resistance of operation of insulation fault detector.

EFFECT: improved reliability, enlarged operating capabilities of protection system.

2 cl, 1 dwg