Why can't a general motors used in plateau area?

Elevation of motor temperature rise,motor corona (high voltage motor) have an adverse effect and dc motor of the reversing.Attention should be paid to the following three aspects:(1) the high altitude,the greater the motor temperature rise,the smaller the output power.But when the low speed permanent magnet generator temperature increases with altitude and lower enough to compensate the influence of altitude on temperature rise When the rated power output of the machine single phase induction motor is the same;(2) should be taken when using high voltage motor in the plateau corona proof measures;(3) the altitude against dc motor commutator,pay attention to the material selection of carbon brush.Why not light load operation machine?Motor light carriage row,can cause:(1) motor power factor is low;(2) the motor efficiency is low.www.facebook.com/guohong.trading Waste can cause equipment,operation is not economic.(1) the load is too large;(2) lack of phase,(3) air duct jam;(4) low speed running time is too long;(5) large power harmonic.