how much wire

[VETE76]

deleted deleted

[Veetail88]

I had no idea either so I just ordered the basic wiring kit from Stein and have not wanted for much since.

[Vlad]

Originally Posted by Veetail88

I had no idea either so I just ordered the basic wiring kit from Stein and have not wanted for much since.

So did I but ordered from Vans. They are not selling wiring harness kits now I've heard.

[chrispratt]

I seemed to recall the #20 and #18 were the dominant sizes needed. Order lots. Tefzel is what you need. If you get it in different colors that helps in identifying the function of the wire, e.g. red = power. Be consistent in the use of color.

Chris

[Jekyll]

My advice is to buy more than you think you will need. In the end, continually reordering more will add more in shipping costs than you might have invested in unused wire. The amount used in an RV doesn't add much weight by using 20 AWG versus 22. 20 is easier to work with IMO. Wire colors can help but wire marking and wiring diagrams are more helpful when it comes time for future maintenance.

20 AWG will fit nicely in pins and socket for DSB and round connectors but, 18 AWG won't fit without trimming some strands. 18 AWG is easier to work with when using molex connectors. High density DSB connectors are different and require smaller wire. I stayed away from those but my radio stack harness has them (thanks to the nice work performed by John Stark, I didn't need to build these).

I tried to stay with red for power, black for ground and white for signals. I bought 50 feet of yellow, orange, blue, green and purple for some signals in stick grips and associated relays. I still have lots of the odd colors left. I color coded my P-mags for easier work behind the engine. I used the wire colors indicated by vendors such at TruTrac auto pilot. I just thought it might help the next guy when my plane is eventually sold (or my son gets it). An EFIS system should come with the wiring harness. I purchased a GRT EIS which came with PVC wires. Tefzel was an option. I should have got the optional tefzel because it seems easier to work with IMO. My EFIS and AHARS are all tefzel.

You can make a SWAG by schetching your component locations and measuring the individual runs then, add a fudge factor. I used a 50% fudge factor and don't have more that 40 feet of each of the 3 primary colors left on the wall. The fudge factor helps when leaving enough for service loops, recutting due to a messed crimp etc. I would really hate to provide you a rough guess and then have you run out or have way too much for your particular system needs. I used 3 times as much white as I did red or black.

You will need twice as many splices and terminals than you originally calculate. Again, terminals, splices and connector pins are cheep when considering shipping costs for small orders. It really erked me to run out of supplies at night when on a roll.

I suggest you make up a load plan with which you list all your components, amp draws and any other pertinent information. This will allow you account for everything you need and calculate your current values. This provides the foundation for selecting wire sizes and circuit protection (C/B or fuse ratings). I would be happy to send mine as a starting point (send an IM).

Tefzel is the wire of choice and AMP PIDG terminals are great. Just make sure you buy quality wiring tools - it will be money well spent.

Jekyll
7A

[Bruce]

You will use a lot of wire.

20---200' both black and white
18---200' both black and white
22---some
wire spoon
lacing cord
zip ties
servo wire Stein 60+' 7 or 8 wire??
Coax-----Stein depends on ant location
Look at wiring diagram for larger size wire
for alt and battery locations.
Also check amp loads.

Your use will vary and need wiring diagram
first to figure it all out. It is a lot easier if
it is on paper first and then you can figure
everything else out.

I would also suggest a EAA workshop to
help you on the amp loads etc.

Good luck.