On 06/08/2010 10:05 AM, Brian Lawson wrote:
On Tue, 8 Jun 2010 11:17:31 -0500, "Karl Townsend"
wrote:
SNIP

............................... Oh, and don't forget
a bleed resistor for the cap.

Ah, come on. You're spoiling Iggy's fun. I got zapped by an electrolytic cap
once. Gets your attention, and then you learn all about bleed resistors and
never forget them.

Karl

Hey Karl,

Ha ha ha. I can't tell you how many fairly decent "injuries" loaded
caps have caused. Not from the voltage you catch, but from the
mechanic reaching into a controller cabinet, getting a "zap" and then
REALLY banging or scraping or even slicing an elbow or their head or
something else when they "jerk" that body part out and hit the cabinet
or a bracket or a screw or some other hard/sharp part of the
controller cabinet !!! Stitches required a number of times.

Lot of caps are used as timers on elevators, so don't have the bleeder
resistor, and when the power is pulled the normal discharge path is
opened, so they stay charged. I think maybe the fact that the power
is supposedly "off" is what causes the violent reaction....makes you
think, in that less than a split-second, that maybe you hadn't turned
everything off, and that maybe you got into the 575 volts or
something.

Brian Lawson,
Bothwell, Ontario.

ps....of course, it's never happened to me. Yeah!! Riiiigghhhtttt !!

So, you didn't go around with the "discharge stick" and make everything
safe?

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com