That should be 25 x 10000 µF. Stay off the Beaujolais Nouveau.
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On 30/11/2008 at 11:05 John RABSON wrote:
>Chris, Mike,
>
>Many thanks. I intended to send directly to Jim, but forgot to change the
>To: field. Yes, the colours are as you describe.
>
>Regarding getting the polarity the wrong way round, in the mid-1960s one
>of my colleagues was called upon to design a power supply with 12 V output
>at some amps. The output capacitance required was a quarter of Farad made
>up of 25 x 1000 µF capacitors connected by busbars. The prototype came
>back from the workshop and he plugged it in.
>
>At point he realised two things: (1) the workshop had got every one of the
>capacitors wrong way round and (2) the mains switch for his bench was
>located behind the unit under test. He walked quickly toward the big red
>button at the end of the lab but didn't get there quickly enough. There
>was a colossal bang and we had a well-decorated ceiling.
>
>73
>John F5VLF
>
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>
>On 29/11/2008 at 09:12 Chris Trayner wrote:
>
>>Hi John,
>>
>>
>>You saw Jim's reply, but
>>
>>> a grey stripe with a 0 on it and this is adjacent to the shorter of the
>>two leads. If I recall correctly, this is the negative lead,
>>
>>Is it a rather oval 0?
>>The tradition seems to be a grey minus (rounded rectangle) within a black
>>oval within a grey band on a black background.
>>A case of not quite making up their minds what the colour scheme is? ;-)
>>
>>You may also find some (for want of a better term) crease lines on the
>>exposed metal end of the can. I think these are purposely weak so that if
>>it goes it blows there, with little containment (in the explosives sense).
>>I can vouch for this, as from time to time one of our students puts one
>>wrong way round on the 15V line. They go off with a very satisfying bang!
>>... followed by other students crowding round the bench to see what had
>>happened. The end of the can shears along the crease lines and the bits
>>peel back like petals, allowing fluffy stuff to be ejected fairly
>>harmlessly.
>>
>>73,
>>Clank
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