I have GT Frame 7E with MarkVI. When the unit starts we noticed the speed is going slowly, we get from the first after giving start alarm say (torque converter not running), we checked the C.B. for torque converter. We found it had overload. We reset it, but it did not accept to reset. The speed of the turbine is raised up but slow compared to normal, and it reached to FSNL and synchronized. The current for starting motor was 85 amp., its normal is about 150amp. The question is, if the torque converter was not run how the speed was going up, and how we can reset the overload on torque converter? What should we do to solve this problem?

Regards.

 

If I understand the question, you are referring to the motor starter for the Torque Adjustor motor, which only controls the torque converter guide vanes. You really need to find and review the Starting Means Schematic Piping Arrangement drawing for details. If the 800 HP Starting Motor is running and the unit is accelerating, the torque converter is pressurized by the energization of solenoid 20TU-1 and transmitting torque, but not at maximum because the Torque Adjustor motor isn't driving the torque converter guide vanes open or closed.

If the circuit breaker of the motor starter is tripped, to reset it you must move the breaker handle to the full open (OFF) position, then you can try reclosing the breaker.

With the unit not running and not on cooldown, I would suggest putting the Torque Adjustor motor starter's HAND-OFF-AUTO switch to HAND, use some kind of clamp-on ammeter on one of the motor phase leads, and use the RAISE and LOWER pushbuttons on the starter door to "stroke" the motor to see why the circuit breaker tripped. (Don't forget to return the switch to AUTO when finished with the testing.) If the amps are high when you are stroking the torque adjustor during this test, then there is something wrong with the torque adjustor. Some of the torque adjustor motors also have brake mechanisms and the break release solenoid has been know to fail on occasion.

I can tell you one thing that usually draws lots of current is trying to lower (close) the torque converter guide vanes when the starting motor is running and the torque converter is pressurized and transmitting torque. That is NOT a desirable condition.

There is also usually a small adjustable pointer on the circuit breaker's overload mechanism. As related to the face of a clock, what position is the pointer in (for example, is it at the 9 o'clock position, or the 12 o'clock position or ?)?

Again, the Torque Adjustor motor (a fractional horsepower motor) doesn't determine if the torque converter transmits torque. If the Starting Motor is running and 20TU-1 is energized and the unit is accelerating, even slowly, the torque converter is transmitting torque from the Starting Motor to the turbine shaft.