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Tips and Warnings Before 1st Power

sglynn

Well Known Member
Do you have any tips or warnings before I apply battery power for the first time to my RV-7A?

I've installed a Dynon Quick Build panel which includes connecting all the ships wires to their Control Module (VP-X like box). I've done single system checks along the way, but really those have been just electrical connectivity.

Is there anything I should look out for? Of course I think everything is connected properly. Everything runs thru a fuse.
 
I did like you, individual checks in process. I learned from some lab engineers to power progressively, check each sub system, and progress slowly through to the end. Operate absolutely everything and be sure things go in the right direction and full range.

I used a power supply and noted amps, not exact, but enough to see a really high draw quickly.

Have fun with the check out. I did a ground check of my AP and found a core wiring issue that had the servos swapped. A complicated one, too, not basic.

I also learned the old analog Whelen strobes wanted 14 volts to fire properly, and 12.0 was not enough. So from then on, I used 14.2 from the power supply.
 
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Make up a pair of flying leads around 3' long from some red and black multi strand store wire - 12 or 14g. Skycraft have loads if you are near Orlando.

Crimp a crocodile clip on either end.

These are really useful for testing, checking and generally temporarily powering all sorts during build. The advantage is they will fry easily if something is amiss, which it shouldn't be of course and it also allows the battery to be placed safely on the floor away from trouble.

Normal stuff about take care with arcing and where they rest but we are all big boys and girls, aren't we ;)

Put the neg lead on the battery first, clamp onto the earth strap, then put the pos lead on the battery and just flick the other end onto the positive feed to check for sparks and potential smoke escape !

Happy - good, now clamp it on and hit that master :D

All done this Monday on our 12 - apart from the fans not working, all was well. Anyone know how to programme a Skyview for the first time ......:rolleyes:
 
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Power Supply

I did like you, individual checks in process. I learned from some lab engineers to power progressively, check each sub system, and progress slowly through to the end. Operate absolutely everything and be sure things go in the right direction and full range.

I used a power supply and noted amps, not exact, but enough to see a really high draw quickly.

Have fun with the check out. I did a ground check of my AP and found a core wiring issue that had the servos swapped. A complicated one, too, not basic.

I also learned the old analog Whelen strobes wanted 14 volts to fire properly, and 12.0 was not enough. So from then on, I used 14.2 from the power supply.

Bill, please what kind of power supply did you use. The ones I'm seeing at Auto Parts store run north of $500 bucks. Yikes. I do like the idea of watching amps being drawn. I could do that with multi-meter but it only goes up to 10 amps.
 
Bill, please what kind of power supply did you use. The ones I'm seeing at Auto Parts store run north of $500 bucks. Yikes. I do like the idea of watching amps being drawn. I could do that with multi-meter but it only goes up to 10 amps.

Real power supplies are not expensive. Here is one of many examples: https://www.dxengineering.com/parts...MIo8Wmn7v-2QIVDIdpCh3GNQKjEAQYASABEgJRn_D_BwE

Buy one for yourself, or get one to share with your buddies. Never run your panels or electronic ignition on a battery charger.

Carl
 
Carl, Im not sure if I understand your caution. Is it to not power the system directly with a charger (not even sure if that is possible) or not hook the battery up to a charger when you turn the panel on. I don't understand enough about low voltage wiring to understand what problems there could be.

Is there a reason to not charge the battery and then run the panel as needed, then recharge the battery when it needs it?

Thanks for the info.

Real power supplies are not expensive. Here is one of many examples: https://www.dxengineering.com/parts...MIo8Wmn7v-2QIVDIdpCh3GNQKjEAQYASABEgJRn_D_BwE

Buy one for yourself, or get one to share with your buddies. Never run your panels or electronic ignition on a battery charger.

Carl
 
Bill, please what kind of power supply did you use. The ones I'm seeing at Auto Parts store run north of $500 bucks. Yikes. I do like the idea of watching amps being drawn. I could do that with multi-meter but it only goes up to 10 amps.

This one is for ham radio and is dead quiet electrically variable voltage settings.

http://www.mfjenterprises.com/Product.php?productid=MFJ-4245MV

They have higher power units as well.

I used it for all the garmin set ups, ap checkout etc. I would not recommend a charger for many reasons. Electrical noise is one.

Edit: YMMV, but I found that 30 amps was really good to have. Going through the G3X interference check out set up requires everything to be turned on at one point or the other. Then in a real life look at what power draws are for a flight configuration, a ground check is safer and cheaper for knowing what to use when the alternator goes out. You can check the voltage readings on main and back up instruments, so many things. I got a power supply with a voltage and amp meter, it will max at about 14.2v. The connectors for the charger and power supply are different, so I got some power pole connectors are rigged the jumper cables, power supply and battery charger so it is easy to select and hook up what ever is needed. I found a lot of work in checkout and it was easily worth the money for the time saved burning fuel. Also, find that I have better things to do in test flights than fiddle with the electrical system. G3X reports amps and the flight record can be checked for verification back on the ground. If I were to do it again, a 45 amp unit would be perfect. Then heated seats, pitot and other accessories can be all powered to see what the total draw is for IFR take-off and landing.
Again YMMV.
 
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What Carl said. And you can go even cheaper, if you limit what you're really trying to do with the supply. Five amps will run almost everything in the plane, one item at a time, if you're just verifying proper wiring. For 1st powerup, I'd want the ability to limit voltage, but also the ability to limit current.This can be very useful as you test each circuit to avoid damage if you've miswired something. Being able to monitor and limit current can tell you a lot about whether you have any issues with a circuit.

A quick google search yielded a couple of <$50 products that would get the job done, but there are dozens of possibilities. I didn't even check ebay for the many diy products.

Once you know everything's wired correctly, you can go to a high current fixed output 12/14V supply to run the whole plane while you sit in it, make airplane noises, and set parameters in all the gadgets.

Charlie
https://www.amazon.com/dp/B00PWNQMYI/ref=asc_df_B00PWNQMYI5411530/?tag=hyprod-20&creative=395033&creativeASIN=B00PWNQMYI&linkCode=df0&hvadid=193992629021&hvpos=1o2&hvnetw=g&hvrand=7098618182552496050&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013908&hvtargid=pla-314802479648

https://www.costway.com/new-30v-5a-110v-precision-variable-dc-power-supply-digital-adjustable-lab-w-clip.html?fee=4&fep=750&utm_source=google&utm_medium=googleshopping&utm_campaign=googleshopping&gclid=CjwKCAjwhcjVBRBHEiwAoDe5xyv9hwlxbYA0xY7I8x2qorC2cEpdk5mDawd8tnmY7vyILOuhSNWcnhoCCAIQAvD_BwE
 
Carl, Im not sure if I understand your caution. Is it to not power the system directly with a charger (not even sure if that is possible) or not hook the battery up to a charger when you turn the panel on. I don't understand enough about low voltage wiring to understand what problems there could be.

Is there a reason to not charge the battery and then run the panel as needed, then recharge the battery when it needs it?

Thanks for the info.

Battery chargers typically are not filtered. For pumping current into a battery it makes little difference. For electronics it does. This means that you should not run the panel on the battery if you have a charger connected.

The pMag install manual has a specific caution on this.

A 30 amp supply will do whatever you need. My dual 10? SkyView Panel, with everything up, draws 20 amps (a lot going to the power hungry GTN-650).

Sure - you can run on battery alone and then recharge but this is a royal PITA.

Carl
 
A few months back a post mentioned a fellow who powered up his project for the first time and the starter IMMEDIATELY engaged. Apparently he had the diode on his starter solenoid wired improperly. Might check that!
 
Battery chargers typically are not filtered. For pumping current into a battery it makes little difference. For electronics it does. This means that you should not run the panel on the battery if you have a charger connected.

This is the first time I've heard this (but then again, this is a BIG forum website). I've always done this when doing things like uploading new software/firmware, since if the unit powers down (say, due to a weak battery) mid-upload, a lot of times the unit is hosed and has to go back to the factory (e.g., XPDR, some EFISes, etc.).

Shouldn't modern electronics be able to handle any ripple from a charger attached to the battery?
 
I bought and am in the thick of panel wiring using the same thing T-short showed, from the same list serve reference.....my GRTs have voltage monitoring so use that and can see voltage dip as I turn things on. Also figured out that my GRT mini-x, which has a battery backup in it, needs 14.2v to charge......so tweaked up the pot on the supply and my panel is running at 14.2 for all testing.

I bought a 30 amp unit, and implemented the Z-14 setup. Right now the supply is powering both busses, but if I need to split them, I'll just buy another 30amp unit. Wicked cheap.
---------

Actually I got mine off amazon https://www.amazon.com/gp/product/B01LATMSGS/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1
 
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A few months back a post mentioned a fellow who powered up his project for the first time and the starter IMMEDIATELY engaged. Apparently he had the diode on his starter solenoid wired improperly. Might check that!

I left off my battery cable, then pulled all breakers, powered the master, checked voltage to the cable, and again while engaging start. It worked as desired and the cable got installed. Don't assume anything -CHECK IT! ;)
 
Have you heard of a builder who spent years building his plane, then forgot to put oil into the engine before first start? A builder can get the same sinking feeling when he realizes that the smoke is a result of connecting the battery backwards.
 
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A few months back a post mentioned a fellow who powered up his project for the first time and the starter IMMEDIATELY engaged. Apparently he had the diode on his starter solenoid wired improperly. Might check that!

Yes can be scary if the prop turns! mine would have no clearance with the workshop ceiling! Thus I disconnected the starter Motor and checked for the clicking Sound of the starter contactor
 
Yes can be scary if the prop turns! mine would have no clearance with the workshop ceiling! Thus I disconnected the starter Motor and checked for the clicking Sound of the starter contactor

Yes, just regard the Alternator testing and Starter testing as part of your first engine start. :)
 
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