Plant Air Wash Supply Fan How to perform in-house infrared trending of Electric Motors High Temp = Ambient = Temperature Rise = Example Report
Plant Air Wash Supply Fan Procedure for trending temperatures on Electric Motors Make sure the motor is at operating temperature (steady-state). High Temp = Ambient = Temperature Rise = The first time the survey is performed, take a photograph of the motor. Take a thermograph (infrared picture) also, if you have an infrared (IR) camera. But you do not need an IR camera for this. If you have one - use it, but a $100 spot radiometer will do just fine. Take a can of barbeque grill paint (E=~.95), SAFELY clean and/or paint the points where you plan on taking the temperatures. Enter the date. Enter the high temperature (HT). Get the high temperature from the inboard bearing. Enter the ambient temperature (AT). Get the ambient temperature from the motor foot or a painted spot on the floor near the motor. The Temperature Rise (Delta-T) will automatically show in the spreadsheet and on the graph. Put this page in a notebook (or the spreadsheet below) and take the notebook to enter the numbers each month/week/day. If the trend is higher temperatures every time you check the motor: Increase the frequency (say from monthly to weekly) and see if the Delta-T continues to rise and watch it closer. Check other connected components, i.e., outboard bearing, winding, coupling. Add other testing, i.e. airborne ultrasonic analysis, vibration analysis, oil and wear particle analysis, eddy current analysis. General Notes: Pick a temperature scale at the beginning of the trending. (Either C - Celsius or F - Fahrenheit and always use the same scale. Keep the surface clean with an air hose, so dust does not build up on the inboard bearing and insulate it. After blowing it off, give the bearing a few minutes to come back to steady state temperature. This trending is predicated on the fact that the Delta-T (HT - AT = Delta-T) will not change if the motor stays in the same condition. If the motor's inboard bearing gets hotter over time, something is wrong. Increase frequency and check other components. The motor's inboard bearing is the pivot point of all other connected components, if something goes wrong anywhere, the bearing heats. Don t worry about being off a few degrees here or there. The idea is that you will be able to see a trend. Even if some errors are introduced, so as long as you use the same repeatable method, you will see the trend.
Plant #1 Air Wash #2 Supply Spray Pump Fan High Temp = 125 Ambient = 87 Temperature Rise = 38 *>129.1 F 110.0 90.0 *<83.6 F
Plant Air Wash Supply Fan Example Motor - Supply Fan 3G High Temp = Ambient = DATE High Temp. Ambient Temp. Rise Notes 06/01/05 125 87 38 07/01/05 129 88 41 08/01/05 133 89 Temperature 44 Rise = 09/01/05 148 90 58 10/01/05 196 92 104 11/01/05 225 95 130 12/01/05 246 95 151 Motor was rewound during shutdown 01/01/05 142 88 54 02/01/05 138 89 49 03/01/05 139 90 49 04/01/05 141 89 52 05/01/05 142 89 53 06/01/06 139 89 50 160 140 120 100 Temperature Rise 151 130 104 80 60 40 38 41 44 58 54 49 49 52 53 50 20 0 Jun-01 Jul-01 Aug-01 Sep-01 Oct-01 Nov-01 Dec-01 Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02
Plant Air Note: Wash Supply SAFELYFan clean dust/dirt from the target area before recording high temp. High Temp = Ambient = Temperature Rise = High Temp.
Plant #1 High Temp = 122 Note: Don t put the ambient temp Air Wash Ambient mark #2 = where 79 it will be affected by the motor temperatures. Supply Spray Pump Fan Temperature Rise = 43 Spot 2 83.4 Spot 1 90.1 Spot 3 87.0
Plant #1 Air Wash #2 Supply Fan #2 High Temp = 178 Ambient = 78 Temperature Rise = 100 *>175.4 F 160.0 140.0 *<60.8 F
Plant #1 Air Wash #1 Supply Fan #1 High Temp = 107 Ambient = 76 Temperature Rise = 31 *>120.5 F 110.0 90.0 70.0 60.0 *<57.5 F
Plant #2 Air Wash #6 Supply CHWP Pump Fan High Temp = 147 Ambient = 75 Temperature Rise = 72 *>152.1 F 150.0 140.0 130.0 110.0 90.0 70.0 *<66.6 F
Plant #2 Air Wash #6 Supply RAF#4A Fan # High Temp = 158 Ambient = 76 Temperature Rise = 82 *>161.3 F 160.0 140.0 *<69.3 F
Plant #2 Air Wash #6 Supply RAF#4D Fan # High Temp = 158 Ambient = 79 Temperature Rise = 79 *>160.0 F 160.0 150.0 140.0 130.0 110.0 90.0 *<78.4 F
Plant #2 Air Wash #6 Supply Spray Pump Fan ##4 High Temp = 176 Ambient = 78 Temperature Rise = 98 *>182.8 F 1 160.0 140.0 *<73.4 F
Plant #2 Air Wash #5 Supply RAF#3EFan # High Temp = 127 Ambient = 75 Temperature Rise = 52 *>134.5 F 130.0 110.0 90.0 70.0 *<65.9 F
Plant #2 Air Wash #5 Supply Fan #3C High Temp = 147 Ambient = 76 Temperature Rise = 71 *>150.1 F 150.0 140.0 130.0 110.0 90.0 70.0 *<66.6 F
Plant #2 Air Wash #5 Supply RAF#3CFan # High Temp = 137 Ambient = 75 Temperature Rise = 62 *>140.2 F 140.0 130.0 110.0 90.0 *<73.8 F
Plant #2 Air Wash #5 Supply Spray Pump Fan ##3 High Temp = 139 Ambient = 76 Temperature Rise = 63 *>143.3 F 140.0 130.0 110.0 90.0 70.0 *<68.1 F