| Author | Message | |||
     Tom Hutchison |
Just in case some of you didnt spot the article in Kitplanes ( June 99) there is a very handy spreadsheet ( excel) that can be downloaded from the Kitplanes web-site . This spreadsheet works out the size of the wire required for each electrical installation , taking into account both the current usage of the installation and the wire run length. (its simple enough even for me to use). www.kitplanes.com ( then click on "whats new ") | |||
| LOUIE LACY |
Tom I need help stopping my strobes from making static over the intercom. I have tried everyting I know how any help (suggestions) would be appreciated Lou llacy@netease.net | |||
| kitpanels |
Hi Lou, Please check a couple of things. Whelen Strobes: All wires are normally 16 gage shielded. The shield should be open (not grounded) on the wing and tail and grounded at the power supply. Next:Intercom check. Most intercoms shield MIC Audio, Phone HI, and Phone LOW. The shields normally are open on the jack side and grounded at the intercom. Some intercom companies have received PMA and FAA approval without shielding their wiring. It has been my experience that 75% of Metal aircraft and 100% of the composite aircraft produce static in intercom and audio panels without shielding. You may laugh but this is what I do in all composite aircraft. IT WORKS!!!! Rule 1. Aircraft Grounding bus bar strap placement is most important. If possible use only 1 to 2 grounding bus bars for the entire aircraft. One is better, but if your aircraft requires 2 or more grounding bus bars place them together. Rule 2. Shield Alternator wiring. Ground the shield to the engine or motor mount. Be sure to leave the other shielded end open (not grounded). Rule 3. Avionics Shielding(except required by Manufacture). Most avionics shielding is grounded at the radio side and open at the other end. When in doubt shield it and ground the shield only at one end. Make sure all grounds go to one central grounding bus bar. Note: If shield wire is open at both ends its useless. Feel free to call me at (503)589-0232. Best Regards, Dennis Whalon, Platinum Avionics | |||
| Tom R. Hutchison |
Great suggestions Dennis! On the subject of strobes, what is the word on Aeroflash units? I like the fact they put the power supplies for the stobes close to the lights. Should cut down on the noise generated by long lengths of supply wires carrying noisy current from a single power supply centrally located. I haven't purchased my nav/strobe lights yet. But I plan to soon. Any thoughts or experiences would be appreciated. Tom | |||
| Jerry |
Hi Tom, and builders: I installed the Whelen strobes using the single power supply with no problems. You must use the wire supplied by them to eliminate the noise as it is properly shieled. The installation is easier since the power has to run to only one location. Mine is under the pilots seat. The unit can be used to power 3 strobes, however I have only the combo units on my wings. No tail light. Good luck. Jerry Sjostrand | |||
| LOUIE LACY |
Tom I think my problem is a grounded loop when you attach your ground bus to the panel you have created the problem . I am going to try an isolated ground bus and see if that works. Any suggestions have tried everything I can think of LOU llacy@netease.net | |||
| Tom R. Hutchison |
Bob Nuckolls, the author/publisher of the AeroElectric Connection is holding Weekend Seminars around the country this summer. See www.aeroelectric.com/seminars.html for more information. You can sign up on-line to express your interest in attending a session in Livermore, CA, Portland, OR or Chino, CA. I am trying to drum up interest in a Portland, OR seminar this summer. If you are interested, please go to the web site and register. Thanks, Tom | |||
| Jay Villalva |
I was just talking to one of the Whelen experts at Sun & Fun (just got back) and was asking about the install of the dual power supplies and wing lights. He told me that I'd be better off with the single power supply. Reasons given - less expensive (almost $200) and more candle power. More back for the buck. When I expressed by concern for the potential noise, he echoed Jerry's comments above. I didn't get a chance to talk with the Aeroflash folks. | |||
| John Harlow |
I have installed the Whelen Comet flash unit with one power supply behind bulkhead 152 and have no problems with interferance. | |||
| LOUIE LACY |
Tom I still can't get rid of the noise I have tried everything call Whelen the radio manufacturer and taken advice from numerous people. Jerry if you see this do you wire the shields from the power pack to the power pack case and do not take the ground wire to aircraft ground from that point. Hope I made this question clear. Lou llacy@netease.net | |||
| Tom R. Hutchison (Tomhutch) |
If you saw my post from April 2000 regarding the home built electrical system seminars put on by Bob Nuckolls, the author/publisher of the AeroElectric Connection. He has scheduled a seminar in Portland, OR on January 13-14, 2001. If you are interested in attending the Portland, seminar you can sign up on-line at: www.aeroelectric.com/seminars.html . Hope to see you there! Tom | |||
| Bill Copeland |
Tom: I am happy to see that you have worked out one of Bob Nuckoll's workshops in Portland. Bob did one here in Livermore two years ago and everyone who attended felt they got more than their money's worth. Of particular help is the reference book that is furnished for the workshop participants. I highly recommend this event to any builder who may be able to make it. For further assistance to those builders facing installation of their wiring, CBROS can furnish a 24X36 copy of our Auto Cad produced wiring diagram for the cost of copying and mailing. Our system is a dual battery/dual alternator set up designed to eliminate the need for a vacuum system. Included on the diagram are a servo driven trim system, Vision Micro System engine instrumentation, S-Tec 50 auto pilot, pulse light landing light system, door alarm and cabin lighting and main and aux power bus system. Interested? contact me off the page at: bnbent@pacbell.net Bill C | |||
| LOUIE LACY (Llacy) |
Radios I would like to relate a problem I had with ordering a King radio to keep someone else from having the same problem. I ordered a KY97A in early October and got the package a few days later. I ordered from Aircraft Spruce and the package didn't appear to have any damage. It was about 2 weeks later that I installed the radio and found it didn't work. I took it to the radio shop in Memphis and the techinician told me the radio had obviously been dropped and a curcuit board inside had been broken. He also said the impact would have broken the face plate and someone had replace it. I sent the radio back to A/C Spruce and they sent it to King who disallowed any repair saying the radio had been damaged.At this point I am out the cost of a new radio. I really don't know what to do other than have them fix it at a cost of another new radio. I would recommed NO ONE buy a radio from A/C Spruce as they packaged this radio in "popcorn" and they told me at King they never did this Lou llacy@netease.net | |||
| Wayne Norris |
I am wiring up my wing tip lights, nav/ strobe with a power suppy at the tip. I am thinking about using the five wire cable, 18g, to run both the lights and the fuel sender. It only takes 5 wires to run everything, the problem may be only the one common grd . 18g should be good for 5Amps at 15'. is anyone else doing this? I shouldn't need shielded wire for the stobes as the power pack is in the tip.?? How to get wire down the tube? I tied a small rag to a string and blew it in with a shop vac, then used that to pull in the wire. Also if you don't have a tube, use a 25'x1" measuring tape, you can push that down the LE with a string tied to the end. | |||
| Gary Markwardt |
Wayne: If you are using the Skysports capacitance fuel probes, you may want to use a shielded wire. I'm not sure how mine is wired since Express did it. But, the fuel gages drop to "empty" & the low fuel warning light comes on every time I transmit. The Express demonstrator has the same issue. Not a big problem, but annoying. Skysports says the fix is to use a shielded cable. Another thought on pulling wires, everytime you pull a wire, pull a small nylon string too. You can leave it in the LE for future upgrades/repairs. | |||
| Brynjar Thordarson (Benny) |
A friend of mine is building a Lancair. He bought a pre-made and pre-wired instrument panel. All his conduits have the best electrical connectors Iv'e seen. They look similar to the old cannon plugs but are made of plastic and much lighter. They come in many different sizes (pin count). Does anyone know where I can buy these plugs. They are not available on this side of the pond. I'm not visiting the States in the near future and I'm wiring up my panel now. Yes, I do it myself. Thanks, and have a whale of a time the next two weeks. Benny | |||
| MarcB |
Benny, They probably use the molded AMP connectors which many shops now use. You can purchase them from most large on-line electronics shops. Try DigiKey (www.digikey.com) as they usually have decent retail pricing on their stuff. The only argument against using them is the lack of good shielding and the creation of another possible failure/short point. But otherwise they're very handy and make component servicing convenient. - Marc | |||
| Eric Holmberg (Erich) |
Hi Benny, I think you are probably thinking about these circular plastic connectors (CPC) from AMP. They are used in a lot of automotive applications -- especially BMW and Audi/VW. http://rocky.digikey.com/scripts/ProductInfo.dll?Site=US&V=17&M=206430-1 http://catalog.tycoelectronics.com/TE/docs/pdf/9/14/167419.pdf http://catalog.tycoelectronics.com/TE/common/images/PartImages/cpc08d.gif I assume you are in Luxembourg from your .lu address. I'm heading out to the UK for New Years and could post the items to you from there if you would like. That would save on shipping for you. Take a look at the Digikey catalog and if you find what you want, send me an email. You can fillout the order, pay for it with a credit card and have them delivered to my work address. -Eric | |||
| amoghadd |
Benny & Eric: When I visited Avionics West, I noticed they are using the same type of connectors on a Turboprop. They were using two AMP connector (part number: 206037-1, 16 pin connectors). I am planning to wire my own panel also (Eric's persuasion!). They cost less than $3 each. | |||
| Anonymous |
AMP CPC connectors are available from sources such as Digi-Key, Newark Electronics, Radar Electric, Hi-Line Electric and most decent Electrical/Electronic supply stores. Make sure to take into account that you also need to buy the contacts, a crimp tool for the contacts, a contact removal tool and the correct cable clamp for the connector body size. This will drive the cost up to around $30 per connection set. Hope this helps. Ted Gaston By the way, this is but one example of the hidden costs that help to establish what you might be charged at your "local avionics shop". | |||
| Brynjar Thordarson (Benny) |
I'd like to thank you all for the help. I've found an outlet here in Luxembourg, in a sidestreet that only professionals know about, and they are able to supply basically anything the heart desires. Happy Holidays to all you eager builders out there. BENNY | |||
| Reinhard Metz |
FYI, I didn't use any connectors, except for a couple of BNCs, where, for example, the radio required it. Connectors can be a pain in the future with breaks, intermittents, etc. For maintenance and general access, such as adding radios, modifying, etc., I used the approach of hinging my panel at the bottom, allowing it to rotate backward at the top about 60 degrees. This has given me enough access to do everything, including a major rearrangement of the radio stack. All the cables and pitot hoses, etc., that leave the panel do so at the left and right bottom corners, aligned with the hinges, so the wiring can handle all the flex there easily. Air ducts are looped a bit and straighten out when the panel is rotated out. Defroser hose is all that has to be disconnected, plus a couple of DZUS wing fasteners that support the rear brackets on the radio stack. All works pretty slick. As for the wing wiring, mine is all continuous - I figure I'll put in connectors if/when the wings ever come off. Reinhard Metz | |||
| Brynjar Thordarson (Benny) |
You're probably right. My panel never has to come out either. I attached legs to it that almost reach the floor and the panel tilts BACK and the opening is about 6 inches. One can work on any equipment with ease. There won't be any connectors in my wings either. I scanned the photo of your aircraft, the one from Custom Planes, and it hangs in my hangar. You're welcome to come see. BENNY. | |||
| Kevin Dennes (Kdennes) |
Good input Reinhard and Benny. I think I will be following your ideas. Question. When you mention 'hinging' is that a piano hinge along the bottom of each panel? What about the main flight instruments panel? I was thinking to leave enough slack on the vacuum lines and electricals to be able to bring the panel forward and work on it without having to work from under the panel. Regards. Kevin (from Downunder) | |||
| Reinhard Metz |
Yes, I have two short piano hinge segments, one on each side, and the whole panel hinges. The vacuum instrument hoses have slack and loop down when the panel is forward, in position. The engine control cables are at the bottom of the panel, so they just flex a bit. Everything else, except air ducts, goes out the bottom sides, and twists as a bundle when the panel is tilted. The hinges are actually mounted on plates, which, in turn, have a pair of rubber shock mounts underneath, per side. The top of the panel mounts in place with a pair of rubber shock mounts per side as well, so the whole panel is isolated. Reinhard | |||
| Kevin Dennes New member Username: Kdennes Post Number: 51 Registered: 01-2001 |
Greetings all for 2003. I am at the stage of wanting to order the navigation and strobe light system for our aircraft. I am getting mixed opinions from here about where to install the control unit for the Whelen system. Some say that I should use the separate control units in each wing tip so that there is no high voltage current being carried in the leading edge, along with the nav antenna. This apparently, can cause interference in the nav equipment. Others have said that it doesn't matter and that a central control unit back in the cabin is OK. I know that there is ample expertise out there among the Express builders to give me some advice on the subject, for which I would be most grateful. Regards. Kevin (from Downunder) | |||
| jharlow Unregistered guest |
Kevin, I used the Whelen sys with the central unit mounted behind the aft bulkhead. No interferance of any kind to date. I have the Comet flash system and love it. John | |||
| Brian McKinney New member Username: Bmckinney Post Number: 42 Registered: 05-2000 |
Good question Kevin! I was wondering the same thing. I already have the separate control units (from the previous builder), and I was just trying to figure out what I was going to do. If I put them in the wingtips, I will have to remove them to calibrate my fuel probes when the time comes. Does anyone see any disadvantages in putting them in the wingtips? Thanks, Brian | |||
| Anonymous |
I am using the Whelen Comet system as well. The power unit is mounted under the rear seat. I haven't experienced any interference problems at all. Jim Butler | |||
| Gary Markwardt Unregistered guest |
I am using the Whelen strobes with the central power unit mounted on the backside of the aft bulkhead. No interference problems at all. | |||
| Kevin Dennes New member Username: Kdennes Post Number: 52 Registered: 01-2001 |
Thank you all. I now know which way I am heading with this issue. Regards. Kevin (from Downunder) | |||
| LOUIE LACY New member Username: Llacy Post Number: 59 Registered: 10-1999 |
What would cause an Alternator field curcuit breaker to trip. If you had an overload of amps why didn't the main breaker trip. I have never had this breaker trip before. Lou | |||
| Jim Oyler New member Username: Midniteoyl Post Number: 12 Registered: 07-2003 |
The Voltage Regulator(VR)/Over Voltage Protection Relay(OVP),alternator,and associated wiring. The field breaker supplies current to the field in your alternator. The current path is from the alternator side of the 60A ALT breaker (sometimes from the main bus, instead), through the field breaker, then through the Alternator half of the master switch, then to the OVP (if present), then to the VR, then to one of the brush holders inside the alternator, through the first slip ring to the rotor winding (field), through the rotor to the second slip ring, to the second brush holder, which is grounded to the alternator case with a short jumper wire. The resistance of the rotor is such that the maximum field current is only 2 to 3A. The field breaker is usually 5A. The VR is just a switch (relay or power transistor)which breaks the field circuit when the alternator output causes the battery (and main voltage) to exceed 14.25V. The VR becomes a pulse width modulator, alternately turning the field full on, and then full off, which causes a decrease in the average field current, and thereby the average alternator output current. A fault (short to ground) of some type will cause the current throught the field breaker to exceed the nominal 2 to 3A. The VR may have developed an internal short to ground, which would trip the field breaker. A fault to ground in the alternator (brush holder or slip ring) would pull lots of current, and likely damage the VR, which in turn would trip the field breaker. Similarly, the wiring from the VR to the alternator is usually shieded. A short from the center conductor to the shield would also trip the field breaker. One cause of tripping unrelated to the above is a high resistance (bad terminal crimp, loose screw)right on the back of the field breaker. The high resistance connection can get hot, conduct heat to the internals of the breaker; the high temp can cause the breaker to trip at what would otherwise be a normal load current. | |||
| Bill Copeland New member Username: Cbros Post Number: 34 Registered: 09-1999 |
WOW! Thanks Jim. Glad to have you on board! Do you make house calls?? Bill C | |||
| Kevin Dennes New member Username: Kdennes Post Number: 65 Registered: 01-2001 |
Jim. Have you ever considered migrating to Sydney, Australia? Regards. Kevin (from Downunder) | |||
| LOUIE LACY New member Username: Llacy Post Number: 60 Registered: 10-1999 |
Jim Thanks for the info. I found the wires to the shiedded connectors to both the field plug and the main connector from the alternator both broken.This was probably from engine vibration because I had the wires streched too tight. I have an alternator from B&C and there is not lug to go from the case to ground is this important The wiring diagram shows a connection to ground LOU | |||
| Jim Oyler New member Username: Midniteoyl Post Number: 13 Registered: 07-2003 |
As long as the mounting bracket is conductive, it will be grounded to the engine. If you have concerns you could tap the alternator case and add a ground wire. Though this shouldn't be required. Most alternators use the case as ground. This could also be a cause of the 'vibration' you mentioned in the Engine thread... Could have been losing power, causing reduced spark, thus causing mis-fires, causing rough running. Test it out when your done. Jim | |||
| Ted Gaston Unregistered guest |
Lou, if you don't connect the ground wire on the alternator as shown, the alternator will not put out. Also for general info, the BNC voltage regulator has an overvoltage protection feature that shunts the input at pin 6 of the VR to ground momentarily when the buss voltage exceeds a preset trip point. This causes the Field Breaker to trip thus disabling the alternator. All this happens pretty fast so you would probably never see any thing unusual until the low voltage warning light goes on. You do have a warning light, right? Jim, the BNC alternator already has a hole tapped for an 6-32 screw just to the right of the terminal block and this is where th F2 terminal needs to be grounded to so the alternator will put out. Ted Gaston EAC Avionics | |||
| Ted Gaston Unregistered guest |
Sorry I couldn't get this uploaded before. Note the Prestolite Alternator detail , bottom of page. F2 must be grounded. we sometimes connect this terminal to the VR case just for good measure. At any rate, Lou, you found your problem and have it fixed, right? Hope this helps. Ted Gaston EAC Avionics | |||
| Jim Oyler New member Username: Midniteoyl Post Number: 16 Registered: 07-2003 |
Thanks Ted So technecally speaking, this is a Generator and not an Alternator as the VR is seperate? Jim | |||
| Reinhard Metz New member Username: Reinhard_metz Post Number: 5 Registered: 03-2003 |
There's another very common and routine way to trip out the field breaker - If you have the B&C voltage regultor with overvoltage protection "crowbar" circuit, it will trip the breaker if the battery voltage goes too high. That will routinely happen in a momentary way when the engine is started right when the starter disengages. The abrupt interruption of current causes an inductive kick and a momentary overvoltage condition. If the field is switched on during cranking, the regulator will see the overvoltage and may then trip the breaker. Mine does it consitently, and the solution is to switch on the field after the engine starts. Reinhard Metz | |||
| Ted Gaston Unregistered guest |
Jim, as I understand it, an alternator outputs a true sine wave (alternating current), then uses a diode bridge to rectify the ac into a dc output. A generator, by virtue of its configuration, is able to output something resembeling dc, thus no need for a rectifier. Both alternator and generator require some form of regulation be they internal or external. The regulator meters current to the rotor winding or field in either case. An alternator is usualy more efficient and lighter in weight for a given output rating which is usualy expressed in maximum amperage at a given voltage,ie (75A 14VDC). Hope that is clear as mud. http://www.sciencejoywagon.com/physicszone/lesson/otherpub/wfendt/generatorengl. htm The above is a cute little applet that illustrates the difference between an alternator and a generators rotor and stator configuration. Ted Gaston EAC Avionics | |||
| Jim Oyler New member Username: Midniteoyl Post Number: 20 Registered: 07-2003 |
Ya - Got that.. My bad. With 99% of my knowledge and terminology usage in the Auto world, the term 'generator' is/was generically used to mean the non-internally regulating devices. Thus my assumption that Louie's 'alternator' didnt need a seperate external ground wire - I assumed it had an internal VR. I'll keep quite now  Jim | |||
| LOUIE LACY New member Username: Llacy Post Number: 61 Registered: 10-1999 |
Sorry I started all this!! I have a VM1000 which tells you everything you need to know about your engine and no I don't work for them!!. I have 260 hours and 2.5 years on my Express and don't have a seperate grounding wire from the Alternator to A/C ground. I assume the ground is thru the connection where the alternator bolts on the engine going to call B&C tomorrow to check LOU | |||
| Jim Oyler New member Username: Midniteoyl Post Number: 21 Registered: 07-2003 |
Let us know. But as Ted says, if the VR is external, you really should ground the VR and ALT case together. In fact, alot of peeps in the auto world go to great lengths to add grounds to the engine compartment (heads, block, frame, ALT, etc) and on high drawing systems, it does seem to help with noise and 'smoothness' of power. I wouldnt think you should have to do that, but grounding the VR to the ALT wouldnt hurt. That, and keeping slack in the wires  . Up to you either way. Jim | |||
| LOUIE LACY New member Username: Llacy Post Number: 65 Registered: 10-1999 |
How do you tell if an encoder supplies digitized information. Does the encoder have to have an RS232 output to send to a GPS. I have a blind encoder and it doesn't send info to the GNC300 GPS unit I have. Any one have a suggestion or name brand that would work?? | |||
| Sven-Ake Eriksson New member Username: Sven Post Number: 14 Registered: 11-1999 |
Louie What type of blind encoder is it? What do you want it to do? | |||
| LOUIE LACY New member Username: Llacy Post Number: 69 Registered: 10-1999 |
I have a Garmin GNC300XL GPS that I want to feed altitude information. Will it work to "pigtail" the leads off a King KT78A (leads A1 thru D4)to the Altitude pins A1 thru D4 on the GNC300XL. The altitude encoder is an Aeri-King and works fine with the KT78A Lou | |||
| Ted Gaston New member Username: Ted_gaston Post Number: 4 Registered: 09-2003 |
Lou, you can "parallel" the grey code inputs (A1-D4) from your KT-78 tray to the GNC 300XL tray for altitude input. You will probably need to diode isolate the mode c lines if you do though depending on how old the KT-78 is since early units were built without internal diode isolation. Since the Garmins are all internaly isolated, you will only have to isolate the transponder. Ted P.S. unless you intend to fly higher than 35kft the D4 bit is not needed. | |||
| Roy Howard Davis New member Username: Royhdavis Post Number: 25 Registered: 01-2003 |
Louie, If you have a recent Ameri-King altitude encoder you may be able to use the serial output to feed the altitude information to the GNC 300XL. That would require only a few wires, save hacking into many parallel lines and fooling with isolation diodes. It has the added benifit of giving you finer resolution 10 or 20 feet instead of 100 for the parallel interface. Seems a shame to have a GPS speced to less then 50 feet accuracy and feed it gross 100 foot increment altitude data when the finer stuff is available. I don't have the manuals for those units in my apartment, so take a quick look in your installation manuals to see if this will work for you. Roy | |||
| Ted Gaston New member Username: Ted_gaston Post Number: 5 Registered: 09-2003 |
Lou, I have not been able to find any manufacturers information that would indicate that Ameri King is planning to build a serializing encoder. I know that the AK 350 is not capable of outputting serial data. While it is true that there are serializing altitude encoders available, your Ameri King is not one of them. A connector compatable replacement is available from Sandia, the SAE5-35 uses the same size and style connector, (not sure about the pin-out) as your AK 350. There is an additional DB9 connector for the serial outputs (2 each). All of the mail order catalog places offer this encoder for around $360.00. Hope this info helps, Ted | |||
| Mike Barney Unregistered guest |
ACK has an encoder with the serial output the A30-8. Spencer Aircraft (1-800-331-4375)has these in stock for $245. Ack A30 comes in two models the -4 which has no serial output and the -8 with both serial and gray. | |||
| Jay Villalva New member Username: Jay Post Number: 4 Registered: 11-1999 |
It's time to buy nav lights/strobes. Any experience with AEROFLASH out there? How do they compare to Whelen? Seem to be half the price... | |||
| Louie Lacy New member Username: Llacy Post Number: 89 Registered: 10-1999 |
Guys I need help and those that know me probably think in more ways than one. I am losing 2 volts from the firewall to the bus bars inside of my Express. I have checked every thing I can think of and no luck. I wired an extra battery to the leads going from the firewall to the elec bus inside the aircraft. I had 12.5 volts at the firewall and 10 volts inside. Where O where are my volts going. Any help would be appreciated. Lou | |||
| Eric Holmberg New member Username: Erich Post Number: 122 Registered: 05-2002 |
Hi Lou, What sort of load (in amps) are you drawing and over what size wire? You can calculate the resistance that would cause the drop for your load by doing R=2.5 / I (where I is your load in amps) and then double-check this against the wiring size that you're using. If that checks out, you may have a bad crimp or solder joint somewhere. A voltmeter is your best friend to figure out the cause -- just check every connection. -Eric |
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