|
|
|
|
|||||
|
||||||
(no email)
Date: Wed Dec 03 2003 - 19:48:50 EST
Please ignore my previous response and accept my apology. I jumped in
without paying enough attention.
Circuit breakers are a combination of thermal detection for detecting minor
overloads over an extended time and a magnetic trip to respond rapidly to
(larger) overloads. Since your short could be a partial one, within the
rating of the circuit breaker, it will not respond. Since loads are
typically not constant, tripping on an internal short less than the rating
couldn't be distinguished from a change in load.
The best solution is the one we installed on Yandina. Since installing it
we haven't had a single electrical fire. :o)
See http://www.yandina.com/hints.htm#NoFire
Andina Foster,
> If I correctly understand the function of a GFI (Ground Fault
> Interrupter), it will trip if there is an anomaly in the ground circuit.
> So you becoming the ground for a faulty hair dryer will be sensed by the
> GFI as an anomaly or fault, and it will almost instantly shut off the
> current to the socket.
>
> Now if I have a cabin heater on my boat connected to a GFI using a
> two-prong plug, and that heater shorts out and starts burning, it's my
> understanding that the GFI will not see a problem in this because the
> ground path is not being changed, so it will continue to allow current
> to flow to the burning heater. Of course there will probably be a
> circuit breaker on the AC circuit the heater is plugged into, and this
> breaker should trip, cutting off the current. But while I'm not sure
> exactly what causes a breaker to trip- heat, maybe?- there seems to be
> plenty of evidence that a circuit breaker might not act in time to shut
> off the power to prevent the heater from starting to burn. And we all
> know where that usually leads.
>
> So my question is...... is there any type of (affordable) electrical
> device that can sense a short circuit the instant it happens and react
> to shut off the current as fast as a GFI does in the event of a ground
> fault? Or is a circuit breaker the only (or best) device available to
> do this?
>
> ______________________________
> C. Marin Faure
> GB36-403 "La Perouse"
> Bellingham, Washington
> _______________________________________________
> http://lists.samurai.com/mailman/listinfo/trawler-world-list
>
> To Unsubscribe send email to
> Include the word "Unsubscribe" (and nothing else) in the subject or body
of the message.
>
_______________________________________________
http://lists.samurai.com/mailman/listinfo/trawler-world-list
To Unsubscribe send email to
Include the word "Unsubscribe" (and nothing else) in the subject or body of the message.
|