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Re: MOT testing

Original poster: "Alexander Rice by way of Terry Fritz <twftesla-at-qwest-dot-net>" <alex-at-rices.myip-dot-org>

>Original poster: "Tim J by way of Terry 
Fritz <twftesla-at-qwest-dot-net>" 
>The best way to measure a MOT is by 
feeding 120V or 240V (depending on MOT) 
>into the secondary. The primary should be 
around 5 to 6 Volts output. Then 
>you take 120V or measured mains voltage 
and divide by primary Volts.
>120 V
>_____  =  20:1 transformer or 2400 VAC
>6 V

that is fine to measure turn ratio

>......then once your done that step use 
the mA current setting to measure 
>output current on the primary. This will 
tell you what sort of drawing rate 
>the transformer has.


um, no actually it will just blow the 
fuse, if a transformer transforms voltage 
in the ratio 1:20 then it transforms 
current in the ratio 20:1 . since you are 
operating the device in reverse you have 
120/20 = 6v but at (guessing 13A 
'secondary' current) 13*20 = 260A which 
will do _bad things_ to your meter! 



Alexander JJ Rice
Rank : G-2 (Wahey!)
"Because the Geek Shall Inherit the Earth