Question

1. Assume that you're a maintenance electrician and are told that a conveyor system powered by a DC motor will run only at its fastest speed. After careful inspection of the equipment, you locate a control knob marked SPEED CONTROL. Adjustment of the control has no effect on the speed of the conveyor-drive belt motor. To troubleshoot the speed control rheostat with the system de-energized, locked, and tagged out, between which two test points (indicated by letters A-H in Figure A-1) would you measure resistance while adjusting the speed-control knob? A. A and B C. G and F B. E and F D. C and G

Answer 1

As the variable speed control resistance is connected between C and G points, we need to measure this value to investigate whether we are getting any change in the rheostat value or not for appropriate speed control operation.

Hence option D will be correct