单选题Moisture absorbed in the windings or condensed on the surface of electrical machinery insulation （）Ais good for long term preserving since most insulation is organic and contains some amountBlowers the insulation value and is a common cause of fault grounds in idle machinesCwill enhance insulation resistance only if it is fresh water and contains no saltDreduces the amount of current supplied or drawn by the machine so horsepower is limited
单选题
Moisture absorbed in the windings or condensed on the surface of electrical machinery insulation （）
A
is good for long term preserving since most insulation is organic and contains some amount
B
lowers the insulation value and is a common cause of fault grounds in idle machines
C
will enhance insulation resistance only if it is fresh water and contains no salt
D
reduces the amount of current supplied or drawn by the machine so horsepower is limited
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