We are thinking about taking readings on some high voltage transformers (13,800 volts) and I was wondering if anyone else is doing this and if they are what type of accelerometer is being used. Also what parameters are being used ( FMAX,Lines of resolution,Peakvue or not, HP filter etc.)

This message has been edited. Last edited by: jm,

I am very afraid of electricity, but what comes in my mind are moving parts, are there cooling fans? If not I would stay far from it using a therma-cam and ultrasound gun with parabolic receiver to detect corona, and occasionally send the transformer oil to test.

How high is the voltage, 415kV? I thought transformer is a static electrical equipment.

Sounds like a chat with our Dr Penrose would be good for you.
Are you there motor doc?

We've been taking vibration readings on our transformers for about a year now. I attended a presentation about transformer vibration at the 2004 EPRI Vibration Technology Users Group Former. The basic idea is that loose windings or loose core blocking can be identified by vibration at 2xLF and/or its harmonics.

We measure at eight positions (each corner, about 18" from the edge and about 5' from the bottom). We use a standard accelerometer, Fmax = 500 Hz, 1600 lines, 4 averages, & 5 Hz HP filter.


Limits for our main transformers (22 / 220 kV)
Frequency WATCH ALERT ALARM
Overall 0.50 0.75 1.00
120 Hz 0.40 0.60 0.80
240 Hz 0.40 0.60 0.80
360 Hz 0.40 0.60 0.80
480 Hz 0.20 0.40 0.60

Limits for our aux transformers
Frequency WATCH ALERT ALARM
Overall 0.35 0.50 0.75
120 Hz 0.25 0.50 1.00
240 Hz 0.15 0.25 0.50
360 Hz 0.15 0.25 0.50
480 Hz 0.15 0.25 0.40

Steve

Nice out of the box thinking !!

Thanks Steve for the info about the transformers I'll give it a try.

Will loose windings or core blocking be detected by thermography?

My resonse was posted in the vibration forum.

A gentle suggestion - imho it would be best to post in only one location. Otherwise people like me get easily confused.

jm :

See if you can contact Chris Meschefske as he was doing this many years ago :

http://appsci.queensu.ca/research/profiles/mechefske/

or

http://me.queensu.ca/people/mechefske/