Collector continuity test

Collector continuity test

• Place the tester prods on the collector blades and check that the tester indicates the passage of current. In the lack of continuity, change the rotor.
• Repeat the above-mentioned operations for all the corresponding pairs of blades.

Rotor insulation test

• Place one tester prod on the collector and the other on the blade pack or on the shaft and check that the tester does not indicate the passage of current. If insulation is lacking (short circuit), change the rotor.
• Repeat the above-mentioned tests for all the collector blades.

Checking brush wear

• To check the brushes, release the brush holder from its plate.

Brush holder insulation test

• Connect one prod of the tester to the brush holder support plate and the other on a positive brush holder and check that the tester does not indicate the passage of current.
• Repeat the test for the other positive brush holder.
• If insulation is lacking, change the brush holder plate.

Minimum brush length

L = 8 mm

• Check that the length of the brushes is within the specified values and that they are not damaged; if necessary, change the whole brush holder plate.
• Also check that the brush springs are not strained and are stiff enough to warrant good contact of the brushes on the collector.