Motor Winding Predictive Testing 5

[testtech]

I am considering the use of surge testing in a predictive testing program. Are any of you conducting surge testing on large numbers of 480V motors? Have you experienced faults that could be blamed on the test procedure? Have you restarted motors after they have failed a surge test?

 

[UKpete]

testtech, re the capacitance testing, I've never seen this done but IEEE 43-2000 Annex B has something to say about it:

"Since the dielectric permittivity of an insulation system is greatly affected by the presence of voids and/or water, an alternating-voltage test is more sensitive than direct-voltage tests with regard to detection of internal insulation problems associated with all types of insulation systems."

It goes on to recommend that both dc hipot and ac testing should be performed.

 

[jbartos]

Suggestion: Visit

http://www.pdma.com/Conoco.html

for:
1.
Electrical reliability technicians are using the PdMA Corporation's self-contained, portable Motor Circuit Evaluator (MCE™) System 3000 to troubleshoot and conduct predictive maintenance on the refinery's 1,870 electric motors, which range in size from 8,000 horsepower to fractional.
2.
"The MCE's found things the surge tester hasn't found,"
3.
The MCE tester being used by Conoco is equipped with PdMA Corp.'s new WinVis™ software. WinVis' user-friendly, Windows interface and complete "Help" system permit quick database set-up based on the plant layout; fast entry or duplication of nameplate data; testing and assessment of a variety of motors in the field; the generation of graphs, charts and reports; and exporting data to other applications.
4.
The MCE's testing capabilities have been expanded to include polarization index, dielectric absorption ratio and commutator bar-to-bar testing.
5.
Etc.

 

[jbartos]

Suggestion: Visit

http://www.motortest.net/BIC_Web/Applications.htm

for:
Union Pacific Railroad, Pat Smith, Electric Shop Supervisor

Union Pacific Railroad overhauls GE and Electro Motive traction motors, generators, and alternators to maintain their locomotive fleet. Pat Smith, Electric Shop Manager, utilizes the D165 Digital Surge Tester in his predictive maintenance program and appreciates the tester's ability to detect problems that other testers cannot.

Upon routine maintenance on some of the fleet's traction motors, Smith found a coil breakdown on a 750hp, 30 year old motor that had been exposed to a variety of environments including hot, cold and dirty. Had Smith not detected the flaw, Union Pacific could have lost well over 4100,000 in delay time on the main line.

 

[jbartos]

Suggestion: Visit

http://www.pjsurgetesters.com/pjwhybuy2.html

for:
Predictive Maintenance Section

 

[edison123]

Lot of useful discussion here reg surge testing as a PM tool. Though I have not failed any motors by surge testing, others differ. However, the goal of PM testing being to ensure the reliable availability of the motor in future, any failures due to surge testing simply points out to the unreliability of the failed motor in service. On this reasoning, I would say that surge testing is a useful PM tool. Ofcourse, a motor that passes isn't necessarily a fail-proof one, but the probability of failure is lowered.

 

[jbartos]

Suggestion to edison123 (Electrical) Nov 9, 2003 marked ///\\Though I have not failed any motors by surge testing, others differ. However, the goal of PM testing being to ensure the reliable availability of the motor in future,
///I think that the goal of PM testing is to establish motor up-to-date conditions.\\ any failures due to surge testing simply points out to the unreliability of the failed motor in service. On this reasoning, I would say that surge testing is a useful PM tool. Ofcourse, a motor that passes isn't necessarily a fail-proof one, but the probability of failure is lowered.
///The probability of failure stays the same; however, the motor conditions may lead to a life-cycle or expected life estimation. This is the product life expectancy prediction.\\\

 

[electricpete]

good comments kumar/edison.

 

[jbartos]

Question to the previous posting: Please, would you point to kumar good comments?

 

[electricpete]

jb
I agreed with everything kumar said. I thought your comments were unfounded and a waste of time. Let's not waste any more time on this.

 

[jbartos]

Suggestion to the previous posting: I just can't seem to find kumar postings. I am finding edison123 posting only. Or am I missing something?

 

[electricpete]

kumar is the name of the person whose handle is edison.

 

[jbartos]

Thank you for clarification.