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From: ahmet erkan (no email)
Date: Tue Sep 02 2003 - 23:07:21 EDT
Lew,
I think you read only half of what I wrote. Here is the other half :
Ahmet Erkan Wrote :
"IMHO it is an undesirable and potentially unsafe situation to rely on
mechanical contacts interrupting large currents on a regular basis. The
manufacturer of the windlass should provide some form of electronic sensing
and maybe timing of the overload condition and either sounding an alarm or
overriding the operator controls. (For mission critical equipment such as a
windlass there should also be an override for the protection circuit that
can be activated in the heat of a battle.)"
Yes I agree with you once again, a circuit breaker or a fuse should be there
as means to survive a malfunction. As said before my humble "WRONG" opinion
is we should not rely on mechanical contacts to interrupt large currents on
a regular basis. (BTW: relays also have mechanical contacts.)
Why do you have to be so hostile when someone is agreeing with you ?
We are all sailors here trying to benefit from each others area of
expertise. Stop this nonsense and buy me a beer when we meet.
If hundreds of amperes can be controlled by modulating a only few amperes
through a transistor, then that is what makes sense to utilize as a means of
protectionl on a regular basis.
Once an arc is striked in a DC circuit, the electrodes (or contacts inside a
circuit breaker) have to be seperated a large distance before the arc
extinguishes, any welder will tell you that. So why use the arc generating
DC circuit breaker to interrupt the current on a regular basis. Norm has a
lot of wisdom about a lot of things but he ought to stop tripping his DC
circuit brakers, just in case the theory is right.
BTW (By The Way) the phrase "Current Flow" is redundant. Current does not
flow, "charge" flows, current is "rate of flow of charge". This is another
misconcemption people have, just like the characteristics of molded case
circuit breakers.
Regards,
Ahmet
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