The test of carbon brushes abrasion value

Generally speaking,the way of test of carbon brushes abrasion value include straighttest and testing the carbon brushes' height difference.

The former has several way as following:

1)taking the measure of differential transformer (touch way);

2)taking the measure of straom gaige (touch way);

3)taking the measure of inductance change(non-touch way);

4)taking the measure of capacitance change(non-touch way);

5)taking the measure of dial gauge(touch way)

The upper way are almost all test in the lab. It should take some technical to do the testBesides,there is the way of radiation to have sometest. We put some radioactivity materialinto the carbon brushes,then we can get some data about the value of commutator andcollector ring. ButWe should consider the affections of brush holder,mechanism vibrancy,temperature,magnetic field. We should have skilled worker to have test.

Now,The main way is to test the difference of carbon brushes height,which is the best way.The instrument is dial gauge.In the old time,there is a way to test the different of weight,which is not very exact because carbon brush adsorb gas and lampblack.We should give special attention that is when the carbon brushes touch with commutatorsor collector rings the glide surface are dark reddishbrown.At the same time the gas medium and thepressure of carbon brushes are often ininvariablenes state.The electricity consistency's wave scope should be adjustedunder +/- 10% at least when electrify. And it can be adjusted under +/- 5%if necessary.Firstly,we test the height of carbon brushes before abrasion. Then,we assure the the glide surface are dark reddish brown.Lastly,we make the machinesrun after clearingof the surface. The glide surface of commutator or collector ringshould be identical uniformity .The glide of carbon brushes and the surface of commutorsand collector rings will be out of the way when there is some different uniformity.And we should take some time to modify.