Chris,
I don't believe anyone's arguing that as far as it goes.  As I read it, the issue turns on what size fuse / breaker you are using.  If the circuit is protected close to the rated draw of the component, then transients could trip it and it could be successfully reset.  If the fuse / breaker is sized way above the rated draw of the component, transients are not going to happen and the fuse/breaker will blow/trip just in time to prevent the wire from melting down - long after the component is fried. 

The basic issue (for me) is that in this scenario, breakers are heavy, expensive, complex (like it or not, they do constitute a failure mode), take up panel space but serve no real purpose.  I'm not against breakers for avionics and the like where you want to protect a delicate, expensive device from damage from transients, but if Paul had a heavier fuse (or breaker), his pump never would have quit in the first place.  One could argue that if he'd had a CB, he might not have had time to trouble shoot his situation and reset it.  As it was, he was real busy staying out of the trees, and IIRC he did turn on the other pump (probably took less time than trouble shooting and reseting a breaker) but it was already too late for that to keep the engine running.  Paul - is that right?

On the one hand, I don't want a flight critical component putting me in the trees on account of some hokey transient, and on the other hand, transients can't destroy a component as robust as a fuel pump.  That's my basic reasoning.

It's a philosophical position ... I'll change it for a good enough reason ... Jim S.


Christopher Barber wrote:

If'n I am not mistaken they are saying a cb MAY reset (due to an intermittent problem or other anomaly).....a fuse WILL NOT.  If I have a choice between MAY and will NOT, I think I will chose MAY......even if the cb reset may point to another problem that must be tended to after a safe landing.  I do not want to stand on principles of what SHOULD be happening if there is an option to get back to Teran soil safely.

 

But what do I know, I am not even staying at a Holiday Inn Express.

 

All the best,

 

Chris

 

\-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On Behalf Of Al Gietzen
Sent: Monday, May 02, 2005 1:17 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Ed's new rotor housings

Group I hate to stir the pot again, but using fuses instead of circuit brakers is asking for dead stick landings. Georges B.   The fuse blew because of a wiring problem; Reset the breaker and it either won’t reset, or it will trip again.  How does that help?   Al -------Original Message-------   From: Rotary motors in aircraft Date: 05/01/05 16:39:07 To: Rotary motors in aircraft Subject: [FlyRotary] Re: Ed's new rotor housings    > Climbed like a rocketship and temps never went above 165 until the engine quit.   Congrats on the glider time, Paul!   My understanding is that the pumps, at least the ones I'm using (or at least WAS using when I used to be able to fly this #@#$ing thing, long ago), are designed to run continuously. I have one Walbro Inline fuel pump-GSL393 (from Tracy) and one Walbro Inline fuel pump-GSL394 from Lightning Motorsports. Both have metal screw in connectors which fit AN adapters. They're fused at 20 amps. Regards, John