ABB DC Machines DMI, Инструкция по эксплуатации и техническому обслуживанию

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Faults and remedies
Commutation
Type of fault Causes and remedies
Brush sparking at the leading edge 1 9 10 9
Brush sparking at the trailing edge 1 9
Slight sparking 1 9 1 19 9 9
Violent sparking with showers 9 10 1 1
Arc or flash 1 10
Sparking of some brushes or sets of brushes 9 1 19 0 9 1
Burning of the rear corner of the brushes 1 1 19 9 0
Vibration and breaking of the brush edges 1 1 0
Brushes wear out too fast 9 1 1 1 0 1 9
Uneven brush wear 1 1 0 9 0 1
Plait interruptions and burning 10 11 1 1 1 0 1
Grooves on the brush sides 1
Grooves on the surfaces of contact 1
Metal particles on the surfaces of contact 1 1 0 1
Uneven commutator wear 11 1 1 1 1 0 9
Grooves on the commutator surface 1 1 1 1 1 1 0 0
Symmetrical stains on the commutator 1 10 1 1
Asymmetrical stains on the commutator 0
Scored commutator surface 1 1 1 1 19 0 9
Possible cause Remedy
1) The brushes are out of neutral zone Reset neutral position
) Asymmetry between the brush holder studs Correct the distance between the studs
) Commutating pole flux too high Increase commutating pole air gap
) Commutating pole flux too low Decrease commutating pole air gap
) Excessive no load operation Use suitable brushes, reduce the number of brushes
) Dirt and oil on the commutator Clean the commutator and identify cause
) Abrasive dust on the brush surfaces Remove the brushes and brush them clean
) Overload Reduce the load
9) Vibrations Check the alignment, rebalance if necessary
10) The armature winding is damaged Repair, rewind if necessary
11) Inadequate ventilation Trace the causes, then consult ABB if necessary
1) Current density at the brushes is too low Reduce the number of brushes
1) Current surges Choose suitable brush types
1) The air is too damp Let in fresh air, select suitable brushes
1) The air is too dry Let in fresh air, select suitable brushes
1) Dust or sand suspended in the air Fit filters and eliminate the causes
1) Gases or acids in the air (*) Let in fresh air, select suitable brushes
1) Excessive brush friction Reduce brush pressure, make use of non-abrasive brushes
19) Brushes not adapted to the commutator Adapt the brushes perfectly, as previously shown
0) Different brush types Use brushes of the same type
1) The commutator is stained when the
machine is not in operation
Raise the brushes
) Brush pressure is too weak Replace the brush spring and brush presser pad
) Excessive brush pressure Replace the brush spring and brush presser pad
) Uneven brush pressure in different brushes Adjust pressure, replace the faulty brush springs if necessary
) The brush holders are not perpendicular
Restore the correct distance between brush holder cases
and commutator ( ÷ . mm)
) The brushes are jammed in the brush holders Clean the brush holders
) Too much play in the brush holder Change brush holder
) Vibrations on the brush holder studs Reinforce the studs with insulating rings
9) The brush holders are not parallel Adjust brush holders
0) The brush holder case is too distant from the
commutator
Adjust distance to about ÷ . mm
1) Uneven current distribution to the brushes
Increase current density; adjust pressure, make use of more
abrasive brushes
) Mica insulator protruding from the commutator Smooth the mica insulator and the edges of the segments
) Burrs on the commutator segments
Remove the burrs, smooth the edges, replace brushes with a
more suitable grade
) Ovalized commutator Turn the commutator
) Broken soldering Solder the commutator lugs
) Scored commutator Turn the commutator
) Protruding commutator segments
Rub the commutator with a pumice stone, turn the
commutator if necessary
) No choke coil where needed Connect the choke coil
9) Choke coil reactance different from specified one Replace the choke coil
(*) Harmful gases which may be present in the air: sulphates, silicones, chlorine, ammonia. consult ABB in these cases