Dear all,
We have the following motor at our site:
HP-60, V-400, RPM-2960, A-79.4, Delta, PF-0.88, Insul. Class F. It is a frame 225M Siemens Motor, manufactured in 1998.
The motor was recently checked by MTS and they say that:
*QUOTE*
"Vibration data was acquired for the subject machine. Vibration amplitudes on motor were recorded as high 0.59 in/s which is beyond critical limits therefore machine can’t be allowed to operate in such condition. Motor Issues need to be addressed , kindly shutdown the machine .
Please note that the motor issue resulting in Line frequency had already been highlighted. Since this frequency lies in close proximity to mechanically induced 2x frequency , it is resulting in beating and therefore overshooting of vibration amplitudes.
MP-723 B - Fire water Pump B (25-Aug-20) PARM = OVERALL
MOH=Motor Outboard Horizontal .218 .219 In/Sec -.0017 -1
MOP=Motor Outboard Horz Peakvue .107 .120 G-s -.012 -10
MOV=Motor Outboard Vertical .201 .166 In/Sec .036 21
MIH=Motor Inboard Horizontal .205 .162 In/Sec .043 27
MIP=Motor Inboard Horz Peakvue .064 .201 G-s -.137 -68
MIV=Motor Inboard Vertical .519 .473 In/Sec .046 10 #
MIA=Motor Inboard Axial .592 .542 In/Sec .050 9 #
PIH=Pump Inboard Horizontal .109 .096 In/Sec .013 14
PIV=Pump Inboard Vertical .163 .125 In/Sec .037 30
PIA=Pump Inboard Axial .122 .097 In/Sec .025 26
POH=Pump Outboard Horizontal .150 .169 In/Sec -.019 -11
POP=Pump Outboard Horz Peakvue 1.571 2.168 G-s -.596 -28
POV=Pump Outboard Vertical .139 .204 In/Sec -.065 -32
POA=Pump Outboard Axial .130 .085 In/Sec .044 52 %
*UNQUOTE*
What do you guys think about the attached frequency spectrum?
What the the checks we can do at shop to verify that the fault is electrical in nature? to be specific how can we test the rotor at shop for health of bars?
Regards,
Mutahir
We have the following motor at our site:
HP-60, V-400, RPM-2960, A-79.4, Delta, PF-0.88, Insul. Class F. It is a frame 225M Siemens Motor, manufactured in 1998.
The motor was recently checked by MTS and they say that:
*QUOTE*
"Vibration data was acquired for the subject machine. Vibration amplitudes on motor were recorded as high 0.59 in/s which is beyond critical limits therefore machine can’t be allowed to operate in such condition. Motor Issues need to be addressed , kindly shutdown the machine .
Please note that the motor issue resulting in Line frequency had already been highlighted. Since this frequency lies in close proximity to mechanically induced 2x frequency , it is resulting in beating and therefore overshooting of vibration amplitudes.
MP-723 B - Fire water Pump B (25-Aug-20) PARM = OVERALL
MOH=Motor Outboard Horizontal .218 .219 In/Sec -.0017 -1
MOP=Motor Outboard Horz Peakvue .107 .120 G-s -.012 -10
MOV=Motor Outboard Vertical .201 .166 In/Sec .036 21
MIH=Motor Inboard Horizontal .205 .162 In/Sec .043 27
MIP=Motor Inboard Horz Peakvue .064 .201 G-s -.137 -68
MIV=Motor Inboard Vertical .519 .473 In/Sec .046 10 #
MIA=Motor Inboard Axial .592 .542 In/Sec .050 9 #
PIH=Pump Inboard Horizontal .109 .096 In/Sec .013 14
PIV=Pump Inboard Vertical .163 .125 In/Sec .037 30
PIA=Pump Inboard Axial .122 .097 In/Sec .025 26
POH=Pump Outboard Horizontal .150 .169 In/Sec -.019 -11
POP=Pump Outboard Horz Peakvue 1.571 2.168 G-s -.596 -28
POV=Pump Outboard Vertical .139 .204 In/Sec -.065 -32
POA=Pump Outboard Axial .130 .085 In/Sec .044 52 %
- 2x & 2.02 ( Line frequency ) are both evident in spectrums .
- Presence of line frequency has been confirmed via coast down data . As soon as machine is shutdown this specific peak vanishes confirming its relation with electromagnetism.
- 2xLF is also observed when motor is run in uncoupled condition in the field.
- Line frequency in conjunction with 2x peak might be resulting in beating and therefore high amplitudes.
- There can only be two reasons for Line frequency . Either soft foot or issues with motor stator / rotor.
- FM team has verified absence of soft foot."
*UNQUOTE*
What do you guys think about the attached frequency spectrum?
What the the checks we can do at shop to verify that the fault is electrical in nature? to be specific how can we test the rotor at shop for health of bars?
Regards,
Mutahir
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