fusible link questions

[Pat Ford]

On Thu, 4 Feb 1999 KD6JDJ at aol.com wrote:

> Date: Thu, 4 Feb 1999 14:51:16 EST
> From: KD6JDJ at aol.com
> To: diy_efi at efi332.eng.ohio-state.edu
> Subject: Re: fusible link questions
> 
>   Reply to Pat Ford
>   I didnt intend to get into a long exchange of design criticism when I put my
> 2 cents in to this fusable link question answering post.

fair enough

>   On some (many) cars the wire that connects the alt. + to the battery+ is
> used as a shunt for the ammeter. 
>   When the ammeter must display both charge and discharge, the load that will
> be monitored for discharge must be connected to the alt. side of the shunt.
>   So, the designers sometimes chose to put the link in that path.
>   Sure there are ocassional problems as a result -- but they are few.

I dissagree

> 
>   I wanted to inform thoes of us that are rewiring an alternator + to battery+
> that a fusable link is not needed. 

just as fuses are optional

> 
>   Also -- An alternator is not designed so that its diodes limit its output
> current. The stator does that.

I think I said that the regulator limits current ( buts it's been a long 
day) ( the mechanical regulators had an overcurrent cutoff)

> 
>   Yeah , I assume that ALL critical wires will be connected dirrectly to the
> battery , for the reason you state.
> 
>   For what it is worth -- Delco puts Avalanch diodes in their negative side of
> the bridge to 'suck up' thoes destructive transients.
> 

I VERY strongly dissagree here just for giggles put a set of jumper 
cables from your car to another without a battery put a scope on the 
battery and watch the "load jump"> there may be diodes there but they 
wont stop the load jump

>   Jerry 
> 

Pat Ford                           email: pford at qnx.com
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