Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
Last revision Both sides next revision
techtalk:ih:elec02a [2018/12/16 23:31]
hippysmack [Brush assembly]
techtalk:ih:elec02a [2018/12/16 23:47]
hippysmack
Line 30: Line 30:
  
 {{  :​techtalk:​ih:​elec:​generator_pic_by_sifty.jpg?​direct&​400|}} {{  :​techtalk:​ih:​elec:​generator_pic_by_sifty.jpg?​direct&​400|}}
-The brush plate is easily removable, and inspection/ cleanup should be straight forward. ((photo by sifty of the XLFORUM ​((http://​xlforum.net/​forums/​showthread.php?​t=1592463&​page=42)) \\+The brush plate is easily removable, and inspection/ cleanup should be straight forward. ((photo by sifty of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=1592463&​page=42)) \\
 Care must be taken when installing the brush plate. \\ Care must be taken when installing the brush plate. \\
 Make sure that the brush- armature connecting wire is not pinched (can short circuit to the frame). \\ Make sure that the brush- armature connecting wire is not pinched (can short circuit to the frame). \\
Line 58: Line 58:
 With the generator cleaned, assembled and on the bench, some simple test with the multimeter in the Ohms scale can tell you a lot about its electrical health. \\ With the generator cleaned, assembled and on the bench, some simple test with the multimeter in the Ohms scale can tell you a lot about its electrical health. \\
 The figures noted here were the results from 2 generators (different models). \\ The figures noted here were the results from 2 generators (different models). \\
-They should be reasonably typical the standard 12V Harley generator.+They should be reasonably typical the standard 12V Harley generator. ​((photo by sifty of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=1592463&​page=42)) 
 + \\
  
 {{  :​techtalk:​ih:​elec:​generator_drawing_2_by_sifty.jpg?​direct&​400|}} {{  :​techtalk:​ih:​elec:​generator_drawing_2_by_sifty.jpg?​direct&​400|}}
-Field winding resistance: \\+**Field winding resistance**: \\
 Placing the leads across the A and F terminals will give you the effective resistance of the field windings (2 windings in series). \\  Placing the leads across the A and F terminals will give you the effective resistance of the field windings (2 windings in series). \\ 
 The armature circuit is not included as in a healthy generator there is no return path via ground to the meter. \\  The armature circuit is not included as in a healthy generator there is no return path via ground to the meter. \\ 
 This should be around the 5.8 ohm mark, a higher figure indicates a possible open circuit, and a lower figure may mean a winding is shorting out somewhere. This should be around the 5.8 ohm mark, a higher figure indicates a possible open circuit, and a lower figure may mean a winding is shorting out somewhere.
  
-Armature resistance: \\+**Armature resistance**: \\
 Placing one lead on a good, clean ground point on the case (shiny metal) and the other on the A terminal, will follow the path through the armature to ground. \\  Placing one lead on a good, clean ground point on the case (shiny metal) and the other on the A terminal, will follow the path through the armature to ground. \\ 
 This should be very low, typically less than 0.6 ohms but can vary as it depends on the brush/​commutator condition. This should be very low, typically less than 0.6 ohms but can vary as it depends on the brush/​commutator condition.
  
-Total resistance: \\+**Total resistance**: \\
 Placing the leads on a good ground point and the F terminal effectively measures the field plus armature circuits in series (from the F terminal, through the field windings, then through the armature to ground). \\ Placing the leads on a good ground point and the F terminal effectively measures the field plus armature circuits in series (from the F terminal, through the field windings, then through the armature to ground). \\
 As a quick check, this result should be very close to the values of the previous tests added together. As a quick check, this result should be very close to the values of the previous tests added together.
Line 77: Line 78:
  
 {{  :​techtalk:​ih:​elec:​generator_drawing_3_by_sifty.jpg?​direct&​400|}} {{  :​techtalk:​ih:​elec:​generator_drawing_3_by_sifty.jpg?​direct&​400|}}
-With the brushes out there are a couple of further tests available: \\ +With the brushes out there are a couple of further tests available: ​((photo by sifty of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=1592463&​page=42)) ​\\ 
-Winding insulation: \\+**Winding insulation**: \\
 Placing one lead on a clean ground point of the casing, and the other on either terminal (do both) should give a very high reading (ideally in the Mega-ohms range). \\ Placing one lead on a clean ground point of the casing, and the other on either terminal (do both) should give a very high reading (ideally in the Mega-ohms range). \\
 This indicates the windings are not shorting to ground anywhere. This indicates the windings are not shorting to ground anywhere.
  
-Winding current: \\+**Winding current**: \\
 Connecting the battery through the multimeter in the Amps scale should result in a DC current of around 2 amps. \\  Connecting the battery through the multimeter in the Amps scale should result in a DC current of around 2 amps. \\ 
 Ohms law states V = IR, so with 12V and a resistance of around 6 ohms I = V/R which gives the 2 amps (will vary in practice as your winding resistance and battery voltage will differ). \\ Ohms law states V = IR, so with 12V and a resistance of around 6 ohms I = V/R which gives the 2 amps (will vary in practice as your winding resistance and battery voltage will differ). \\
  
-Motor test: \\+**Motor test**: \\
 This is probably the best indication, as a generator that will motor with voltage applied indicates all is well with the commutator / brush assembly. \\ This is probably the best indication, as a generator that will motor with voltage applied indicates all is well with the commutator / brush assembly. \\
 Jumper leads from a good battery were used and a short piece of wire (applied +12V to the A terminal, and -12V to the case and F terminal simultaneously). \\ Jumper leads from a good battery were used and a short piece of wire (applied +12V to the A terminal, and -12V to the case and F terminal simultaneously). \\