Megger testing procedures 3

[bp168]

Hi,

I've been asked to find an IEEE or equivalent test procedure for meggering from the T-leads in an MCC cubicle to the motor in the field. Any help would be much appreciated.

Ben

 

[dpc]

http://www.netaworld.org/Category.cfm?CategoryID=3

 

[benlanz]

What is the operating voltage of your cables?

Benjamin Lanz
Vice Chair of IEEE 400
Sr. Application Engineer
IMCORP- Power Cable Reliability Consultants

 

[HCBFlash]

NFPA 70E should help you also
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Start each day off with a smile
,,, then you've at least that much out of the way!

 

[Zogzog]

I think you meant to say NFPA 70B

Scott Peterson
Training Manager
Power Plus Engineering

http://www.epowerplus.com

 

[54494060]

This is what I refer to when asked. There may be changes (Rev's) but pretty standard for Rotating Equipment and Cables. Corrections welcome.

IEEE STANDARD 43-1974 (29) ACCEPTANCE CRITERION FOR INSULATION
For Rotating Equipment
•IR is equal to or greater than 1 Megohm plus rated equipment KV.

MEGGER

IEE STANDARD NO. 43.1974
ACCEPTANCE CRITERION:
•IR IS EQUAL TO OR GREATER THAN 1 MEGOHM + RATED KV.

MOTOR RATING VOLTAGE DC MEGOHMETER (Test Voltage)
460/575 500 or 1000
2300/2400 1000 or 2500
4000/41602 2500
6600/6900 5000

POLARIZATION INDEX

PI = IR Measurement at 10 minutes
(Divided by)IR Measurement at 1 minute

ACCEPTANCE CRITERION:
Usually 2

IEEE STANDARDS: 690-1984(1), 422-1986(43), 43-1974 (29)
(for cable Insulation testing)

 

[benlanz]

Again, I do not completely understand the application. However, I will give a warning that the IEEE standards noted are not applicable for shielded MV cables with extruded insulation. Per IEEE 400-2001 DC should not be used as it can damage aged cable and will not detect most defects. I recommend at least a AC withstand or, better yet, a PD stress test. Let me know if you have any questions.

Kind regards,

-Ben


Benjamin Lanz
Vice Chair of IEEE 400
Sr. Application Engineer
IMCORP- Power Cable Reliability Consultants

 

[hogdawg]

Most of the regs that I deal with is 2 X operating voltage + 100v