Quote:
Originally Posted by Ether
Does anyone have any data on the relative heat dissipation capability of the mini compared to the CIM?
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Only a little data now, will try to get more later:
We fitted a CIM and a mini-CIM with thermocouples to measure temperature on their brush guides; this is the hottest non-moving internal part -- the moving armature windings get a few degrees hotter. On a Magtrol brake dynamometer, we ran the CIM at its normal load, which is about 0.45 N-m drawing about 27 Ampere, per the data sheet. We ran the mini-CIM at 2/3 of that load, 0.30 N-m drawing about 17 Ampere.
As has already been noted, the mini-CIM operating at 2/3 the torque load of a CIM is actually running more efficiently; thus its power losses (waste heat) are lower than the CIMs in both relative and absolute terms.
Our thermocouple measurements showed the CIM brush guide reaching 125 degrees Celsius after eight minutes, while the mini-CIM brush guide took twelve minutes to reach the same temperature.
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07-06-2013, 20:36
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