Mike - when you say 'physical protection' are you talking about anti
chaffing or 'p' clip support?
I have put both of my cbs in the panel but have tried to anchor every 3-4''.
Where I breach the firewall I have put in a proper bulkhead seal which I
will fill with silicone once the panel is finally in.
Steve Pitt #403
----- Original Message -----
From: "M.J. Gregory" <m.j.gregory@talk21.com>
Subject: RE: Europa-List: Wiring query
>
> Simon,
>
> A further point to note about Issue 4 of the circuit diagram is that the
30
> amp slow blow fuses for both the battery and the alternator supply cable
> protection are positioned on the firewall side as close as conveniently
> possible to their power sources. This gives maximum protection to the
> cables leading through to the cockpit and bus bars against the possibility
> of a short circuit to ground causing them to smoke. If instead of these
> fuses you have installed circuit breakers that are mounted on your panel,
> then you must take particular care to ensure that you have good physical
> protection for the cables leading up to them. This applies not just to
your
> initial installation, but to any subsequent maintenance or modification
you
> may do that might affect the integrity of these cables during the life of
> the aircraft.
>
> The wiring to engage the isolator is not given a fuse or circuit breaker
to
> protect it because it is on the ground side of the device. In contrast,
> there is protection for the starter relay solenoid circuit because that is
> supplying a positive to cause it to engage.
>
> Regards
>
> Mike
> Europa Club Safety Officer
>
>
> A common misconception is that fuses or circuit breakers protect devices.
> Not so. The protection is for the wire, or more precisely, the insulation
> on the wire. A given wire-insulation combination can carry a certain
> maximum current for a specified maximum temperature increase, and circuit
> protection devices are selected on this basis.
>
> If in your example the wire is both short in length and physically
protected
> from contacting anything that could make a short circuit in the event the
> insulation is compromised, protection in the form of a fuse or CB is not
> required.
>
>
> Best regards,
>
> Rob Housman
> Europa XS Tri-Gear A070
> Airframe complete
> Irvine, CA
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com]On Behalf Of Simon Smith
> To: europa-list@matronics.com
> Subject: Europa-List: Wiring query
>
>
> Hi all,
>
> I have virtually completed the wiring in accordance with the diagram on
> Page 25-11 issue 4 which I believe is the latest version. I am using a
> battery isolator and, after discussion with Andy, I have swapped the 30amp
> slow blow fuses on the battery feed and regulator feed to 25 amp CB's.
>
> I crossed my fingers and powered it up and fortunately everything seems to
> work. One thing that I have noticed though is that if the batt master CB
is
> pulled, power is removed from the aircraft but the isolator remains
> energised (which I think is correct according to the diagram). Does it
> matter that there is no fuse/cb protecting the isolator?
>
> Cheers
>
> Simon
> #504 G-BZTN
> 80% done 90% left to do!
>
>
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