Message Board Thread - "Detector anomaly while close to a Transformer"

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Detector anomaly while close to a Transformer PdMJoe 9/13/2010
While performing a routine inspection of electrical equipment I noticed that the detector on My PM695 displayed horizontal bars whenever I got close to a medium voltage transformer. whenever I auto reset the level & span or moved away it returned to normal.
Is this a normal condition caused by a magnetic field around the transformer or is the camera picking up a transformer anomaly? I have been scanning this equipment for three years and have not noticed this prior.
 
Re:Detector anomaly while close to a Transformer Gary Orlove 9/14/2010
Its a normal condition when working near magnetic fields with IR cameras. Some cameras exhibit the phenomenon more than others.

FLIR Systems cameras comply to the general EMC and magnetic field standards:
* EN 61000-6-2:2005 (Immunity)
* EN 61000-6-3:2001 (Emission)
* FCC 47 CFR Part 15 Class B (Emission)
* EN 61000-4-8, Test level 5 for contiuous field (severe insdustrial environment)

FLIR cameras have successfully been used in Aluminium and other refineries where you find high currents. Magnetic field strength declines by the distance to the third power, so if any disturbance is seen, it often helps to bring the camera away from the bus bar just a little. It is impossible to tell weather you will see disturbance or not in an individual case. In certain conditions images might be disturbed. How much and in which way depends on frequency, direction and strength.
 
Re:Detector anomaly while close to a Transformer PdMJoe 9/14/2010
Thanks Gary
 
Re:Detector anomaly while close to a Transformer Pete 9/22/2010
Be careful staying in those high EMF fields with your camera for too long. I used our P640 under our generator, performing IR on our 25kv CT(s). Basically screwed up the camera so much it was off by over 100 degf high. Went back in with our cheap little E-4 and never had a problem. I have experienced messed up displays in the past on opur P595, but it never messed with the actual temperature. Typical distance for our camera "issues" is about 4' for the 25kv.

Lucky for me Flir fixed the camera as part of the annual calibration.
 
Re:Detector anomaly while close to a Transformer PdMJoe 9/23/2010
Thanks for the advice Gary,
Like I stated before, I've not noticed this in the past while scanning this type of equipment. I've also been around Main generators in upwards of 800 MW and not had this, so I was curious if the camera was picking up an anomaly in the transformer. obviously the image is unusable in that state so a person would have to back off from the target and thus hopefully protect the detector. Thanks again
 
Re:Detector anomaly while close to a Transformer PdMJoe 9/23/2010
Sorry I meant thanks Pete
 


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