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Originally Posted by efoote868
Would you think that the energy the "load CIM" dissipates would change its resistance characteristics?
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If the load CIM gets hot, it will change its load vs speed characteristics.
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Are there any steps we can take to mitigate the effect?
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Richard addressed that concern in his earlier post. With the proposed load CIM test rig, it takes only a second or two to load the test CIM and record the loaded speed and current. The short test times mitigate the effect: close the load switch, record the speed and current, open the load switch.
Safety warning: If you decide to use such a setup, make sure to use a heavy-duty load switch and that is properly insulated/shielded (including cables). I'm not sure how much instantaneous voltage will be generated when the load switch is opened. Maybe someone (some adult) could test this. If the voltages are high enough to be a concern, a condenser (old-school term) -- like the ones that were used to keep the automobile distributor points from pitting back in the pre-electronic-ignition days -- could be placed across the load switch.