DYNAMOMETER TESTING
A dynamometer is a device used to measure power. Commonly they are used to measure
the power output from motors (although not exclusively). They are used extensively in
industry and sometimes for familiar things such as power output of motor car engines
during tuning operations (particularly for competition)
In the application of measuring power output from motors, normally the rotating output
shaft of the motor drives a variable load. The torque and RPM are measured as the load
is varied and the power calculated from them. Commonly the results are depicted in a
graphical form, with torque and power graphed against RPM.
Measuring the low power output of the motors used for model solar cars presents some
difficulties. With output power in the range of 0.5 to 8.0 Watts, small unaccounted for
losses significantly degrade the accuracy.
A very basic dynamometer was constructed see, sketch below for the concept.
(^) Tension
(^) Adjust
Tension 1 Tension 2
Cord
Spring
Balance
1
Spring
Balance
2
Motor
(^) Pulley
This dynamometer is very basic but overcomes the problem of unaccounted for losses , as
all the loads are taken directly on the motor with no additional bearings used. The motor