Electrical 3
11/6/05 12 Hours
I was on a roll today at the hangar. I received the ANL current limiters from B & C, so they have been loosely mounted for now, until I get the correct countersunk head screws for it. They're just being held there for now with AN3's. Once I have them screwed down tight, I can go ahead and make some copper strip to link them to the contactors .
Next electrical task was wiring the flap sensor. While I was wiring it, Steve came by and I had him make the contraption to hold the sensor. You can see that on the fuselage pages. wiring this was a pretty simple task. Once again, the Molex plugs work a treat. I need some more though. These were my last ones. This shows about where the sensor will be mounted. I categorised that with fuselage today though.
Look, now the flap sensor is working too!
The next things I need to wire are the fuel flow sensor and the fuel pump. The fuel pump uses a funny relay too, so that's gonna be fun.
11/7/05 7.5 Hours
After getting back from the hoby and electronics stores, I finished the flap position sensor installation and then set about more electrical stuff.
I sometimes get messed up with what pages to put this stuff on. Is this electrical? Yes... Is it fuselage? Yes... So, I don't know.. I'll document it here today!
I bought some 6-32 size rod end bearings from the hobby shop to complete the flap position sensor. I joint at the sensor end of the rod was tightened without the ball in there and filled with epoxy to set it rigid. This is because the sensor is hinged at the top for easy removal, and if there are three pivots, it'll just flop all over and never work. He it is in the down position... Looks like the up position? Well, here it is, but at the flaps, it's down.
And the up position....
As you can see, I have a five way connector on there in the above pics. While I was at the electronics store, I bought some three way ones, so I decided to replace this one and fix my wire routing. I also put some heat shrink for strain relief on the AOA flap switch wires after I took this photo.
Time to move forward... In the cabin, and figuratively. Two things that needed doing were the fuel flow sensor, and the fuel pump. I got the fuel flow sensor wired to the EFIS One's Analogue 2 ports. Pin 6 was 12v, Pin 19 was ground, and Pin 7 was the pulse sensor channel. This was pretty easy, but I've not set up the sensor in the E1 yet. The box is still out on the bench so I can get some access around the back of the firewall.
This is the fuel sensor end. Once again, the Molex plugs come in real handy.all these wires look a bit of a mess right now, but they'll all be tucked away inside the centre console when it's finally installed some time soon.
The fuel pump has this really strange relay that operates it. There are little hooks on it that you loop a wire on and solder. So, here I decided a pigtail was the way to go. Again, Molex connector. I got away with a five way here, and to pins are connected together that go to the fuel pump +ve terminal.
The completed unit. I drew a diagram on the FADEC wiring diagram of the connector pin outs. X1 is the black wire.
A great place to mount this thing turned out to be right by the fuel selector. Hopefully, there won't be any vapours leaking around here for this relay to spark up! Actually, this relay is sealed. I bet this is the reason why!
On Wednesday, I'll finish this off, and run the wires to the wing roots for the nav, landing and taxi lights. Once these are in, I think the wiring is finished aft of the panel. Ahead of the panel, I have to run the alternator switch wires, and that's about it. I'm almost there.
11/9/05 10 Hours
Today was a day of more wiring. It seems like it takes forever to do, and that you don't see much progress too. I just plodded on. I took a break from the fuel pump wiring and put the Reiff preheater bands around the cylinders on the engine. Around here, these will be a necessity for keeping the engine cozy in the sub zero temperatures.
Of course, I had to give them a go. They get pretty hot. Too hot to touch in fact. The cylinders suck up a lot of heat too. These will be more efficient when the cowling is on and there's a blanket over it to keep it warm at night.
Next I finished the ANL current limiters as my order came from McMaster-Carr for the countersunk screws. I had to make some bus bar to connect everything together down here. The 60 amp one is for the main alternator, and the 40 amp one is for the aux alternator. I had a discussion with Bill at B & C about what to use for the aux alternator, because on the Z-12 AeroElectric scheme, it shows a fusible link. Bill said that the SD20 is really cabable of being a 40 amp alternator, and that it just doesn't turn fast enough on the vacuum pad to ever make this. He said they use a 40 amp ANL with their STC's for different aircraft. I guess it must be OK for me right?! You can see the lead here is the B lead to the main alternator.
Back to the fuel pump... I had to call Aerosance to figure out their wiring diagram for the fuel pump relay. I thought I'd figured it out, but I guess I couldn't see why the fuel pump would go on when the switch was in the on position. It was apparently obvious though, as the relay contact for 'on' are normally closed, so all you need is power to come through the switch. I don't know why I wasn't seeing this. I guess I had a moment of stupidity hit me.
I continued on then, now it was all figured out. Here, I've made the
connections to the pump. I couldn't for the life of me find any info in the pump
literature about which terminal was positive and which was negative, or even whether it
matters. I'd long since removed the PVC cables and threw them in the bin. I took a gamble
and wired it as you can see. When I got home, I checked Dan's site, as I know he has one
of these pumps... Yep, of course I had them the wrong way round! Tomorrow, I'll be
switching them then. What a pain! It's not pleasant doing these things right now, as I
picked up a couple of injuries playing soccer last Monday. I have a big graze on my knee
which makes bending it in trousers a bit tricky, and a black toe which makes bending it in
general tricky 
I scored a goal though!
Time to start working my way along the switches to make sure they're all done. Not much to show for pictures at this stage, as all the wires are starting to look the same! First switch was my Master. I needed to run the main alternator field wire from the Main bus to the switch. Did that. Then, the aux alternator, same thing. Did that. The next switch is E-Bus Feed, which is done anyway. Then the EFIS and Auto Pilot switches are both already done too. Now we get into the lights. First up is Nav. These weren't done, so off I went running more wires. The tail light had been done sometime last year, but I'd not ran anything out to the wings yet. Now's the time. It also needed power from the bus.
Here's the rear Nav light working. The others will have to wait until the wings go on, which might not be very long....
Next switch along is the Strobes. They're all done. Wires have been hanging out the sides of the plane for an eternity for those! Next up is Landing light and Taxi light. They needed running too. Did that. Then the map lights. I got the runs to the map lights done, but not the feed from the battery bus yet. I want to be able to turn these on without having the master on. Might be usefull. I also have those interior lights I can turn on too from the battery bus. Do I smell a chance of a dead battery coming on in my future? Did some dummy leave his lights on? Anyone got any jump leads?
Once the map lights have been run, the only things left are the Com 2 antenna in the left wing, the autopilot cable to the right wing, and the GPS antenna for the GX-60 through the firewall. For the first, I need to order some more RG400 from SteinAir, and the second, I've absolutely no idea how I'm going to route that thick cable through there. I think I'm going to have to drill another hole in the spar to pass through. Once that's completed, I'm 100% with all my cabin wiring. Finito. Soon I can concentrate on getting ready to put the wings on. When they go on, I don't want to be pulling them off and on too many times. I'd like to just maybe take them off once, tops. If I can get away with not pulling them off at all, I'll be even happier!
5/14/2006 9 Hours
One of the many things we did today was try to trouble shoot a couple of issues I've been having with the Aileron trim and the flap position microswitch for the AOA. Every now and then, the aileron trim has been running away, and I've never been able to figure out why. Since this has been occuring, the AOA flap switch isn't working correctly. This one is a bit harder to figure out.
We systematically went through each step of the wiring to figure out what the deal was. For the aileron trim, it seemed like we had a switch shorting out somehow, so we dismantled the stick grip, and found nothing. For some reason it's all working correctly again. We don't know why though. Everytime I go to the hangar now, I'm going to try it and see if it runs away again. Strange. It's not a sticking relay, we elinated that as a potential issue first.
So, the AOA thingy. Now this is a very strange one. The AOA Pro from Proprietary Software Systems, now (Advanced Flight Systems) has a wire that grounds when the flaps go down. It was working fine, but one day, it stopped. I've no idea why. So, I set about checking it a while ago with a multimeter, and discovered that when the multimeter is in diode check mode (outputting a current) and the probes touched across the microswitch, that the AOA works as it should! Hmmm. So, today, I confirmed my suspicions with a AA battery. We soldered some wires to the battery, and connected it across the microswitch. Sure enough the AOA sensed the flaps correctly. Now, I've no idea why this would be the case. I need to call them tomorrow to help me figure out why!
Anybody have any ideas?
Oh, one other thing. In the notes above, I switched my wires to be the same as I've seen on other sites. That turned out to be a mistake! I had to swap them over again to make the pump blow instead of suck.
I did some more trouble shooting on the AOA flap sensor switch issue today, and discovered that when the EFIS is on, the flap switch works correctly. Hmmm. There's definitely something wrong here. Anyway, pulling the fuse to the EFIS is just like switching it off, so there's something happening somewhere else. If I put the fuse back in, and disconnect all the cables from the EFIS, the AOA works too. Now, I'm going to plug the EFIS stuff in one by one until the AOA stops working to see where the culprit lies.
I also did a bit of wiring today. Firewall forward stuff though. I got the secondary alternator done, and started to get the oil senders done. Here's the lower end of the alternater 'B' lead. It's 10AWG. I managed to find the ring terminals from McMaster Carr. That place is a Godsend. If nowhere else has it, chances are they will... 'cept for a 5/8"-18 UNF to 1/8" NPT adaptor that is.
Here's the sender end. I taped the adel clamps to stop them rotating. I don't want to tighten them up yet until I spiral wrap all this stuff. I never recieved any documentation for the oil pressure sender. I've no idea what each wire does. I can only assume that Black is GND, Red is +ve and green is signal. I want to confirm that with Aerosance before I go connecting this up though. I will also have the oil temp wiring running along with this little lot. I can't fit it yet though, coz I'm waiting on an adaptor (mentioned above).
5/18/2006 2 Hours
Tonight, I continued with wiring inside the fuselage. I threaded the Com 2 antenna cable through the spar, and took it up to the radio stack. I still need to add the plug and connect it too the radio though.
I also sorted out the marker beacon antenna wiring. This runs into the back of the SL-15 audio panel. It's tough to see in this shot, but it's the copper coloured cable to the right of the white ones.
I started threading the auto pilot cable through from the wing servo too. The reason I've moved into the cabin is because I need to square away all my wiring in there so I can fit the centre console for good. This has to be in place to start the engine on Memorial Day weekend.