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Date: Mon, 09 May 2005 08:17:42 -0500
From: Jim Sower <canarder@frontiernet.net>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] EC2 redundancy
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If we've mostly agreed that we're sizing fuse/CB to protect the wire and 
not the component, what would be the point of redundant feeds to a 
common power line inside the box?
What failure mode are we protecting against with this scheme? ... Jim S.

Al Gietzen wrote:

>> At some point I asked Tracy if redundant power leads were truly 
> redundant.
>
>> As I recall, he stated that the two power leads are connected (to each
>
>> other) inside the box.
>
> I'm pretty sure I had the same conversation, and the same answer.
>
> You may recall last week I mentioned in a posting the I had redundant 
> critical circuits, and “almost” redundant power to the EC2. The power 
> inputs are common inside the box (at least on mine). However; you can 
> still run two feeds and isolate them just outside the box with diodes. 
> At least gives you redundancy to that point, and there are redundant 
> controllers inside.
>
> Best to use Schottky diode for lower forward drop – might allow 
> running a bit longer if your alternator fails and you are running your 
> batteries down.
>
> Al
>