Downhole sensors gather vital data for the health of an ESP system. Not only do the sensor readings help indicate the flow pattern; they also help indicate further issues such as plugging and degradation of the ESP system. Once a system has grounded on a single phase, sensor readings are lost, and operators must rely on current and frequency for the system to operate efficiently. In unconventional applications of ESP, operators see a small difference between no load, no flow and gas locking conditions. This small difference is due to the de-rating of motors used in order to get the fluid to surface in the severe applications. When the sensor readings typically are lost, operators are no longer able to accurately diagnose the reason for a shutdown. Adding the Tubing Temperature Transducers (TTT's) helps regain an indication of motor temperature along with load on the system. When operators have a drop in the tubing temperature this indicates the system is not able to get as much fluid to surface either indicating gas locking or a no-load condition which results in heating of the downhole system, particularly the motor. All these possible scenarios cause degradation of the ESP equipment and can cause pre-mature failure. If the system is set up with TTT's operators can shut-in the well to avoid extended periods of excessive heating caused by either gas locking or no flow conditions. Single phase to ground conditions occur frequently, however this paper does not address the root cause of a single-phase grounds, rather it addresses what the operator can do to operate efficiently when a unit has grounded out a single phase.

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