>> Since my last message I have counted up what cable I have left, and as I
> had
>> a record of what I bought my usage was as follows :
>
> Richard,
> Your message HAS to be the wisest one on net for some time! I
> have saved it for consideration as I design my electrical circuit since it
> helps surmise the quantities required - I think............
> Thanks Again,
> Ferg
> A064
>
>
Fergus
Well thank you kind sir.
When I said I had some cable left, I meant that the figures I gave were my
actual usage in the aircraft and that I bought more.
Individual usage will depend very much on how you do it, where you run the
cables and what view you take on panel removal.
My panel removal is helped by a PFA approved inspection panel in the
firewall. With the top cowling off I can get the instrument panel out in
about 5 minutes, and back again in about 10 (although there is one bolt into
stiffnut which is a pain!). Everything has a connector in it.
1. Down the tunnel
2. For the mags
3. For firewall connections (regulator starter)
4. For Engine connections (sensors)
5. Overhead radio/headset connections
6. Three antenna connections - BNC
7. The Airmaster prop cable (I wasn't allowed to cut this and put it in my
standard connector !)
8. The vacuum pipe to the pump
9. Pitot and static connections.
And that's it (I think).
For the cable run to the fuel pump, fuel gauge sender, flap motor, P1 & P2
PTT, and stall warner I used screened cable, earth on the screen, as it
doesn't kink and keeps the pair of cables together neatly. I didn't measure
weight but it can be only a negligible amount heavier.
Fuel pump & Flap motor used 20AWG screened, the others 22AWG.
The capacity of these cables is amazing. 22AWG looks really small but will
carry 4 amps continuous. And the insulation is amazingly thin.
I didn't use any 24AWG. I didn't use the cable provided by Europa for the
fuel gauge (? mod 60). I did use the 5 core 28AWG (?) cable for the trim
motor, but it needs care in the connection.
I am of two minds about the 4AWG for the main starter circuit. It has a
greater cross-section than the terminals on both the solenoid and the
starter itself. I really think that 6AWG would do the job - saving 2 kilos -
but I accept that there might be voltage drops which would cause problems on
a cold day.
All cables are positioned in the looms using heat shrink, which was only
heated at the last stage. Hope I don't need any changes ! I used 5 colours
and several sizes ! Photos available if anyone is interested.
As the ANR headset guru I also have provided a 9v feed from my overhead
radio/headset panel to drive ANR without messing with batteries. The
connectors in the roof are 5 pin XLR, and I have made up two adaptors
(called splitters by professionals) to allow the use of standard headsets.
So it's time to go to bed so I will stop blowing my trumpet now !
Richard
Richard F.W. Holder 01279 842804 (POTS)
Bell House, Bell Lane, 01279 842942 (fax)
Widford, Ware, Herts, 07860 367423 (mobile)
SG12 8SH email : rholder@avnet.co.uk
PA-28-181 : Piper Archer : G-JANA, EGSG (Stapleford)
Europa Classic Tri-gear : G-OWWW, being built.
|