Q:

Is an inertia dynamometer more repeatable then an eddy current dynamometer (or vice versa)?

  A:

No. The eddy current dynamometer is no more or less repeatable than an inertial dynamometer.  If designed properly, repeatability should be expected of both machines.

The inertia dynamometer, often referred to as “dummy-proof”, performs only one type of test – which virtually eliminates the possibility of human-error.  This has often been confused with repeatability, which is representative of the machine, not its level of complexity.