Post on 01-Aug-2018
Benefits of KnowingBenefits of KnowingYour CommutatorYour Commutator
ProfilesProfiles
Mark RokusekMark Rokusek Gary LozowskiGary LozowskiFoundation Coal PRB OperationFoundation Coal PRB Operation National Electrical CarbonNational Electrical Carbon
June 7, 2007 W.M.E.A. Billings MTJune 7, 2007 W.M.E.A. Billings MT
A reasonably round commutator surface is neededA reasonably round commutator surface is neededto expect good brush performance, brush life, to expect good brush performance, brush life,
commutator, brush holder and spring life.commutator, brush holder and spring life.
Main Purpose of a BrushMain Purpose of a Brush
To conduct electrical current from it, to aTo conduct electrical current from it, to arotating Commutator or Slip Ringrotating Commutator or Slip Ring
In the case of a DC Motor with a Commutator, it needsIn the case of a DC Motor with a Commutator, it needsto conduct current to each and every commutator to conduct current to each and every commutator segmentsegment
It needs to have intimate contact with the comm.It needs to have intimate contact with the comm.segments to conduct current without arcingsegments to conduct current without arcing
( Arcing or sparking is current going through air )( Arcing or sparking is current going through air )
Commutator / Brush Demands Commutator / Brush Demands (e.g. 1045 KW GE generator)(e.g. 1045 KW GE generator)
12001200 RPMRPM20 Rev20 Rev’’s per seconds per second1,728,000 Rev1,728,000 Rev’’s per day, 630 million / years per day, 630 million / year3,000 comm bars per second3,000 comm bars per second6,123 FPM 6,123 FPM -- 70 MPH70 MPH300,000 miles in 6 months300,000 miles in 6 months120 commutation cycles per second120 commutation cycles per second.00084 seconds to switch 733 amps.00084 seconds to switch 733 amps
MMS 6000MMS 6000
Commutator Condition IndicatorsCommutator Condition Indicators
Situation
Runout ( TIR )
Bar to BarVariance
Undercut Depth
NEW
Less than
.0015
Less than
.0002
.050
or more
IN
SERVICE
Less than
.003
Less than
.0003
.020
or more
NEEDS REPAIR
More than
.003
More than
.0003
.010
or less
( MBTB )
Brush Path 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2.0
Mils
)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Brush Path 2 2 12 Mar 2003 ( 8:48:43 am) (209) 209 Bars 1.18 mil : 45-10 0.47 : 10-11 0.078 0.075 0 0
These brushes have an easy job of conducting current toThese brushes have an easy job of conducting current toEach commutator segment with 1.18 mils TIR.Each commutator segment with 1.18 mils TIR.
BrushesBrushes
Commutator
Track 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2.0
Mils
)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Track 2 2 19 Mar 2002 ( 4:06:18 pm) (211) 211 Bars 3.39 mil : 1-86 0.44 : 86-87 0.086 0.082 0 0
These brushes will have a harder job trying to contact eachThese brushes will have a harder job trying to contact eachCommutator segment with 3.39 mils TIR & .44 Max. BTBCommutator segment with 3.39 mils TIR & .44 Max. BTB
Track 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2.0
Mils
)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Track 2 2 19 Mar 2002 ( 4:06:18 pm) (211) 211 Bars 3.39 mil : 1-86 0.44 : 86-87 0.086 0.082 0 0
These brushes will have a harder job trying to contact eachCommutator segment with 3.39 mils TIR & .44 Max. BTB
Track 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2.0
Mils
)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Track 2 2 19 Mar 2002 ( 4:06:18 pm) (211) 211 Bars 3.39 mil : 1-86 0.44 : 86-87 0.086 0.082 0 0
These brushes will have a harder job trying to contact eachCommutator segment with 3.39 mils TIR & .44 Max. BTB
Recording 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 2 2 25 Jan 2005 ( 2:39:23 pm) (174) 174 Bars 2.52 mil : 133-85 0.82 : 17-18 0.162 0.174 0 0
.0025” TIR
It’s not just theTIR number
but alsothe shape of the
commutator that needsto be considered
Recording 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 2 2 25 Jan 2005 ( 2:39:23 pm) (174) 174 Bars 2.52 mil : 133-85 0.82 : 17-18 0.162 0.174 0 0
Some commutatorProfiles almost makeit impossible for thebrush to do its jobwithout sparking
These brushes are from a motor with a very rough comm.Brush wear is different since TIR of each brush path is different.
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
.0 M
ils)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
5
10
15
20
25
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
7 MIL test 2 9 Apr 2007 ( 2:36:50 pm) (27) 27 Bars 6.83 mil : 9-25 1.79 : 26-27 0.512 0.335 0 0
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
.0 M
ils)
2.0
0.0
-2.0
-2.0
0.0
2.0
2.0 0.0 -2.0 -2.0 0.0 2.0
1
5
10
15
20
25
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
7 MIL test 2 9 Apr 2007 ( 2:36:50 pm) (27) 27 Bars 6.83 mil : 9-25 1.79 : 26-27 0.512 0.335 0 0
SM3
DG
4 HG
5 HG
4 SG4
SM2DG
3
HG
3
HG
2
SG2
SM1
SG3
DG
2
DG
1
HG
1
SG1
Deck Layout of Marion 8200 draglinewith TIR of each commutator
.0023
.0014”
.0038”
.0033”.0010”
.0024” .0046”.0017”
.0024” .0039”.0037” .0005” .0011”
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
DG4 Aug 29, 2006 9 6 Sep 1996 ( 4:41:08 am) (209) 209 Bars 1.38 mil : 152-2 0.36 : 12-13 0.070 0.064 0 0
DG4.0014” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HG5 Aug 29, 2006 8 6 Sep 1996 ( 4:37:03 am) (209) 209 Bars 1.02 mil : 207-26 0.55 : 209-1 0.069 0.063 0 0
HG5.001” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HG4 Aug 29, 2006 7 6 Sep 1996 ( 4:31:09 am) (211) 211 Bars 20.16 mil : 208-179 19.53 : 207-208 0.271 1.884 0 3
HG4.0024” TIR
3 Low AreasStarting
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG4 Aug 29, 2006 6 6 Sep 1996 ( 4:23:52 am) (147) 147 Bars 2.33 mil : 99-56 1.30 : 99-100 0.171 0.200 0 79
SG4.0023” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
20
40
60
80
100
120
140
160
180
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
DG3 Aug 29, 2006 2 6 Sep 1996 ( 4:03:36 am) (205) 205 Bars 3.78 mil : 148-1 0.32 : 9-10 0.081 0.062 0 0
DG3.0038” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HG3 Aug 29, 2006 1 6 Sep 1996 ( 3:59:49 am) (210) 210 Bars 4.61 mil : 51-97 0.98 : 171-172 0.149 0.140 0 0
HG3.0046” TIR
.004”
.003” TIR isMaximum
Recommended
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HG2 Aug 29, 2006 3 6 Sep 1996 ( 4:07:18 am) (211) 211 Bars 1.74 mil : 71-201 0.55 : 177-178 0.079 0.074 0 0
HG2.0017” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
10
20
30
40
5060
70
80
90
100
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG2 Aug 29, 2006 5 6 Sep 1996 ( 4:13:39 am) (105) 105 Bars 3.30 mil : 49-79 0.86 : 12-13 0.133 0.171 0 87
SG2.0033” TIR
3 Low AreasStarting
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
10
20
30
40
5060
70
80
90
100
110
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG3 Tr1 Aug 29, 2006 14 6 Sep 1996 ( 5:00:40 am) (111) 111 Bars 4.53 mil : 9-92 1.42 : 111-1 0.291 0.261 0 84
SG3 TR # 1.0045” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
6080
100
120
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG3 Tr2 Aug 29, 2006 15 6 Sep 1996 ( 5:02:58 am) (137) 137 Bars 3.70 mil : 31-110 0.83 : 51-52 0.249 0.182 0 92
SG3 TR # 2.0037” TIR
It’s not just theTIR number
but alsothe shape of the
commutator that needsto be considered
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
10
20
30
40
50
60
70
80
90
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG3 Tr3 Aug 29, 2006 16 6 Sep 1996 ( 5:05:13 am) (98) 98 Bars 2.72 mil : 21-82 1.02 : 70-71 0.277 0.248 0 81
SG3 TR # 3.0027” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
10
20
30
40
50
60
70
80
90
100
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG3 Tr4 Aug 29, 2006 17 6 Sep 1996 ( 5:07:49 am) (103) 103 Bars 2.99 mil : 58-83 1.14 : 75-76 0.278 0.241 0 81
SG3 TR # 4.00299” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
10
20
30
40
5060
70
80
90
100
110
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG3 Tr1 Aug 29, 2006 14 6 Sep 1996 ( 5:00:40 am) (111) 111 Bars 4.53 mil : 9-92 0.97 : 5-6 0.291 0.247 0 84
SG3 Tr2 Aug 29, 2006 15 6 Sep 1996 ( 5:02:58 am) (137) 137 Bars 3.70 mil : 31-110 0.83 : 51-52 0.249 0.182 0 92
SG3 Tr3 Aug 29, 2006 16 6 Sep 1996 ( 5:05:13 am) (98) 98 Bars 2.72 mil : 21-82 1.02 : 70-71 0.277 0.248 0 81
SG3 Tr4 Aug 29, 2006 17 6 Sep 1996 ( 5:07:49 am) (103) 103 Bars 2.99 mil : 58-83 1.14 : 75-76 0.278 0.241 0 81
SG3All Tracks
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
DG2 Aug 29, 2006 13 6 Sep 1996 ( 4:57:32 am) (207) 207 Bars 0.55 mil : 169-87 0.28 : 22-23 0.071 0.052 0 0
DG2.00055” TIRExcellent TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
DG1 Aug 29, 2006 12 6 Sep 1996 ( 4:54:53 am) (211) 211 Bars 1.10 mil : 8-112 0.55 : 7-8 0.069 0.063 0 0
DG1.0011” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
200
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HG1 Aug 29, 2006 11 6 Sep 1996 ( 4:49:56 am) (208) 208 Bars 2.40 mil : 174-95 0.75 : 62-63 0.146 0.136 0 0
HG1.0024” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
50
100
150
200
250
300
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG1 Aug 29, 2006 10 6 Sep 1996 ( 4:46:18 am) (305) 305 Bars 3.39 mil : 85-218 0.40 : 47-48 0.048 0.054 0 0
SG1.0039” TIR
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
50
100
150
200
250
300
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG1 Aug 29, 2006 10 6 Sep 1996 ( 4:46:18 am) (305) 305 Bars 3.39 mil : 85-218 0.40 : 47-48 0.048 0.054 0 0
SG1.0039” TIR
Off Center
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
50
100
150
200
250
300
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
SG1 Aug 29, 2006 10 6 Sep 1996 ( 4:46:18 am) (305) 305 Bars 3.39 mil : 85-218 0.40 : 47-48 0.048 0.054 0 0
SG1.0039” TIR
Off Center
.0046”TIRMachinedOff center
.0046”TIRMachinedOff center
When turningCommutators in a lathe . . . You mustZero to the bearing
journal diameterbefore taking a cut.
Hourglass shape ofthese brush pathsindicates a veryuntrue commutator.Dirty, sluggish and weak springs or pitted brush holders can cause this. Stubbing BH orientation mightalso be a factor.
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
HM4 tr1 Aug 29, 2006 2 6 Sep 1996 ( 6:42:50 am) (178) 178 Bars 8.90 mil : 54-92 3.31 : 56-57 0.537 0.705 0 0
HM4.0089” TIR
.00044” TIR3600 RPMSlip Ring
1.0
1.0
0.0
.00044” TIR3600 RPMSlip Ring
0.5
0.5
0.0
.00044” TIR3600 RPMSlip Ring
Small BUMP on slip ring OD maycause problems
Brush
Having the brush perform properly is a team effortby the brush, commutator, brush holder and springs. It takes proper mechanical adjustment of these parts. Uniform air gap settings of the poles is also very important. Electrical settings like neutral and interpole strength also need to be correct for good operation of DC Motors & Generators.
Mark RokusekFoundation Coal West
Currently and last 7 years in our
Predictive Maintenance Group
Previously, 11 years in Motor Repair where I had a great opportunity to see machines already brokenand repair them.
. . . now I’m more involved with keeping them fromBreaking
Using many diagnostic tools: vibration analysis,thermal imaging, Comm profiling & visual inspections.
New Sandblasted
New Sandblasted
Sandblasted pins createrough surfaces & causesluggish action of fingers
New, shiny,Low frictionpivot pins
Rough surface from sandblastingprevents fast action of brushes
DO NOT bead, grit or sand BLAST BRUSH HOLDERS
Use liquid solvents if cleaning is necessary
Bead blasted surface inside carbonway is roughIt causes brushes to hang-up momentarily or
act sluggish.
Anything that impedes FAST ACTION of brushas it needs to follow the contour of the never
perfect comm. surface will cause sparking andfaster brush / comm wear.
New Bead Blasted CurrentDamaged
43.1°C
101.3°C
60
80
100
Unequal current distribution fromUnequal spring force to brushes
41.7°C
105.6°C
60
80
100
Uniform current distribution with new springs
DO NOT bead, grit or sand BLAST springs
Use liquid solvents if cleaning is necessary
Sluggish springs cause arcing with fasterbrush wear and possible comm. damage
Probably better off replacing with NEW springs
New springs every 5 years or 6 to 10 brushchanges is good maintenance practice.
Springs usually cost same or less than brush
SG4
Single area ofBurned Barsaround comm.circumference
SG.004” TIR
One burned areaor low spot
Sh. 4 / hoist gen
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Sh. 4 / hoist gen 1 22 Aug 2002 ( 7:13:50 am) (173) 173 Bars 2.96 mil : 165-50 1.30 : 98-99 0.165 0.187 0 0 O.B. brush path / Comm. was re-insulated
Aug 22HG
Sh. 4 hoist gen / OB path
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Sh. 4 hoist gen / OB path 1 13 Sep 2002 ( 8:54:58 am) (176) 176 Bars 2.52 mil : 49-36 1.14 : 45-46 0.216 0.222 0 7 OB. path
Sep 13HG
Only getsworse
with time
Bar discoloration from high heat
How often should you Profile commutators ?
- At least every six months
- Possibly every 2 months
- As conditions warrant:
excessive sparking
rapid brush wear
Trending this information will help you
better plan your maintenance efforts.
Recording 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80100
120
140
160
180
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 2 2 21 Jan 2007 ( 1:25:16 am) (184) 184 Bars 1.10 mil : 53-104 0.20 : 178-179 0.052 0.039 0 0
787 wheel motorJan 21
.0011” TIR
Recording 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80100
120
140
160
180
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 2 2 28 Feb 2007 ( 9:52:43 am) (184) 184 Bars 3.43 mil : 137-175 0.74 : 139-140 0.139 0.153 0 3
787 wheel motorFeb 23
.0034” TIR
314 Right/ IB.
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
314 Right/ IB. 14 28 Jan 2003 (12:57:51 pm) (184) 184 Bars 4.88 mil : 70-99 0.71 : 71-72 0.196 0.147 0 0
788 wheel motorPress & Torque Concerns
.0049” TIR
Recording 1
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 1 1 1 Oct 2003 (11:25:28 am) (175) 175 Bars 5.32 mil : 161-58 0.83 : 175-1 0.095 0.093 0 23
824X motorOff Center.0053” TIR
Outboard
Recording 5
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 5 5 1 Oct 2003 (11:38:05 am) (174) 174 Bars 1.14 mil : 5-65 0.12 : 19-20 0.041 0.037 0 53
824X motorOff Center ?.0011” TIRCenter
Recording 6
Profiler MAS - Commutator - Radial PlotR
adia
l Sca
le (
+/- 2
Mils
)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 6 6 1 Oct 2003 (11:40:56 am) (174) 174 Bars 4.76 mil : 53-124 0.59 : 174-1 0.084 0.075 0 46
824X motorOff Center.0047” TIRInboard
Beginning stages of Pitch Bar Burning
Recording 2
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Recording 2 2 25 Jan 2005 ( 2:39:23 pm) (174) 174 Bars 2.52 mil : 133-85 0.82 : 17-18 0.162 0.174 0 0
824X motorPitch Bar Burning
.0025” TIR
Crow d gen./ Bad bearing housin
Profiler MAS - Commutator - Radial Plot
Rad
ial S
cale
( +/
- 2 M
ils)
2
0
-2
-2
0
2
2 0 -2 -2 0 2
1
20
40
60
80
100
120
140
160
180
Recording Plot Rec# Recording start (Actual) Size TIR Max BTB Mean BTB Std dev Suspect Hi Mica Remark
Crowd gen./ Bad bearing housin 1 10 Mar 2005 ( 1:14:05 pm) (198) 198 Bars 3.11 mil : 150-184 0.74 : 54-55 0.126 0.155 0 0 It has burning bars.
Crowd GeneratorPitch Bar Burning
Bad Bearing Housing.0031” TIR
How about commutator TIR almost .250”
Yes, ¼ of an inch
On an older MD824 Hoist Motor
Simulated profile
Inside area of commutator that hasStall damage ( high heat )
Heat damaged group of segments
Group of commutator segmentsin normal condition
Bars with broken risers, therefore open armaturecircuit - - these bars are not carrying current.
Better performance from brushes,commutators, brush holders andbrush springs can be realized ifthese parts are maintained in
good operating condition.
Commutator Profiling Can Help !
Questions ?
Thank you !