Patent ID: 8763683

Claim:
A control circuit for a coiled tubing injector for raising or lowering coiled tubing into a well, the injector including an injector motor to power an injector drive mechanism, the injector drive mechanism engaging the coiled tubing to raise or lower the coiled tubing, the circuit comprising: a circuit controller for varying power to the injector motor to maintain a substantially constant weight on bit; the injector motor is electrically powered; the circuit controller varies amperage to the injector motor to maintain a substantially constant weight-on-bit by exerting an upward force on the coiled tubing less than the coiled tubing string weight; an in hole adjuster for controlling amperage to the motor and control in hole forces applied to the coiled tubing; and another controller for controlling amperage to the motor and control out of hole forces applied to the coiled tubing.