Thanks Arby,
Perhaps what I need is a remote battery switch.
http://bluesea.
I would like to avoid running the high power leads any longer than
necessary, yet still have the disconnect be within reach of the helm. I
agree that a system failure on a boat isn't as likely to make the news
as a dragster going off the track, but careening down the marina looking
for the cheapest boat to plow into isn't a very attractive proposition
either!
May never happen, maybe I'm fighting a battle that doesn't exist?
-Tom
Arby Bernt wrote:
>
> Drag racers are using 1000a controllers (sometimes several) to control
> brushed motors typically. If the controller fuses (turns into a fused
> mass), power is sent directly to the motor for a wild ride into the
> accident files. A boat typically has a much weaker power-to-wieght
> ratio, and would gently go up to hull speed as if at WOT. It's
> doubtful the boat would be accelarating out of control, however.
> Reliabiliy is important in a boat, and a disconnect is just another
> electromechanical interface to go bad. A battery selector switch
> serves the same purpose, and it's contacts are cleaned each time the
> switch is rotated.
> If you choose to use a brushless motor and controller, a fused
> controller will melt down your batteries instead, so make sure you
> have a fuse, rated at twice your peak draw, somewhere in the string.
>
> Be Well,
> Arby
>
> On Feb 8, 2010, at 11:01 PM, "Tom" <boat_works@yahoo.
> <mailto:boat_works@yahoo.
>
>>
>>
>> After 17 months of part-time building my 21' launch, I'm wrapping up
>> construciton and starting to work out wiring details.
>> I try to glean all I can from this group and the EV folks. Something
>> I see in the cars, but not so much in boats is an emergency
>> disconnect switch in case of powertrain runaway.
>> It seems that it might be really handy in the event of a failure to
>> be able to totally disable the battery bank without leaving the helm.
>> The EVs sometimes use "big red switches" within reach of the driver,
>> and sometimes use a mechanical cable to actuate a switch remotely.
>> Since I want to keep the battery bank wiring as short as possible,
>> I'm leaning toward the latter method.
>> This disconnect would be in addition to the keyswitch actuated
>> battery bank contactor and typical fusing.
>> Any thoughts?
>> -Tom
>>
>
No comments:
Post a Comment