hey guys.....I actually pulled this picture below from another thread. I beleive the guys name is ( "Propwash".....thanks propwash!) anyways..........i'm looking at this and i'm trying to figure out exactly where would the reciver's go?


Some of you guys are going to say i'm going a little over kill on this plane ( a aviation models 33% yak) , but i have been saving every penny i can , to get this plane. I want to take the extra stepss i so i can have some fail safe (or at least more safe than running only one power system)


I just need help on exactly what to get , and how to wire everything up. i don't want to buy something and find out later that i didn't need it. I know i want to run the "Smartfly power expander , I think i'll need to regulator's as well...right? Two MPI smart switches (for on and off power) , three larger type Li-poly packs (what size? 2400's ?)


aaaahh crap..i could keep rambeling , but if i could just get some input here..that would be awesome. I'm picking up the airplane tommarow afternoon at cheif aircrfat!..YES!!............wwOOooOoo!


JEFFRO503

If you use the Smart-Fly regulators, they offer an option failsafe switch/charge jack for them. I'd probably use than versus an MPI switch.
Single switch for both batteries but since its a failsafe and fails with the circuit closed (on) you don't really need 2.

The setup you have illistrated would IMO be the ideal setup except get rid of the MPI switches and use the JR charge switches. The failsafe switches are nice but will drain your battery slightly when in the off position and are more expensive. The odds that 2 switches are going to fail at the same time is nil. I run almost a identical system to this and am very happy with it. The RX goes atop of the Expander and the Expander has all the connections.

SHawn

THe picture is from the old expander. Get the Expander Pro.
I just got the new one and it is great.
I had the old one in another plane.
I have the expander, two HD switches with dean's plugs (Smartfly sells)
And I have two 1800maH NiCad packs from Radical RC. (with dean's plugs)
THe system works great and only drops 0.1 volts at 2 amps load.

Fromeco states that the badger failsafe switch's current draw isn't enough to warrant unplugging a battery. From their knowledge base:

unless you leave your plane for a week or two......

Ok then.........thanks you guys for all the help. Sorry for being such a dumb***** , i've just never ran one of these set ups before.


so..........On the smartfly power expander.....should i go for the regular power expander , or the "pro" or "sport" version?

and to make things clear........i need........

one POWER EXPANDER

TWO REGUALTORS?.......OR DO I NEED TWO for a redundant system? or do i need one of these...since the power expander has these installed inside it'self or what.....confused here.

do i need 3 switches.....one for ignition , two for the redundant system?


just trying to make a short list , so i can pick everything up at once.


JEFFRO503

Working on my setup now. I will have...

1 Power Expander Pro (has some new nice features - definitely want to get it - Sport isn't out yet).

2 Fromeco Regulators wired with deans connectors in and out

2 Fromeco badger switches wired with deans in and out

2 Fromeco lithium ion batteries wired with deans connectors


My battery, switch and regulator setup is redundant and feeds both power expander power input/output connectors with failsafe switches.

Like someone said, regular switches are ok - you don't NEED the failsafe switches since you have a redundant battery supply and redundant switches but I'm paranoid.

The Smart-Fly turbo reg and super reg both have redundant regulator circuitry but a single control circuit - so, if the control circuit fails, its over with but these are still both very nice units. I just went with the fromeco since they are both seperate units.

Hi

For a 30 / 35 % machine this is the setup I would use.

Dual Switches
Dual Regulators
Dual Batteries
Single Receiver

The Negatives are there is a possibility the batteries want draw down equally

Ian

If you get the Fromeco switched regulators they draw 3mA... will drain a full 2400 in 1 month.

That being said, I don't unplug mine... I do watch them closely and I charge the night before I fly.

As for drawing the batts down evenly... the Fromeco regs are adjustable. Just set them up to be within .01V of each other and you won't have any issue with the packs drawing down evenly... at least I don't.

Am i missing something? If your only running one receiver , what if it fails? I thought that you had to have two "complete' power systems going to make it a full redundant system? everything is doubled up , but the reciver. wouldn't it be safer to hook up a second reciver to this? I'm just asking , because i thought that was what a redundant system was?.......maybe i'm wrong.

OK.....i did some more searching through a bunch of different threads on this "redundancy system"......and it seems alot of the guys who use this ( with the dual receiver's anyways) have the left side of the airplane set up on one receiver , and the right side set up with another receiver.


My question is this.........if you have your airplane set up like this........and one reciver fails , can you still have a chance at landing your airplane with one side not working? What about a dual servo on the rudder,.......if one of the servo's has failed because of the receiver for that side gave up........i wonder if it would lock up and make it so the other servo couldn't be in use either.


man this is giving me a headache!


Does anyone have a "dual receiver" , with a smartfly power expander diagram or picture? if i could physically see it , i think it would help. I know i'll still have questions.........it's probably so simple , i'm over looking things i think.

Add a Smartfly Batshare between the batteries & the switches. Now your system is perfect.

The new power expander Pro basically has a batshare built in I beileve.

It depends, if it was a power problem to one receiver, the servos would not lock up but I'd never put a single control surface crossed between 2 receivers. If the receiver had other problems such as a crystal falling out, it would end up locking up or worse. So, you'd have servos fighting each other.

Don from Don's Hobby Shop in Salina, KS recommends that you cross the elevator and aileron (left receiver - left aileron, right elevator. right receiver - right aileron, left elevator) to compensate for the loss of a control surface on a specific side.

Never tried to land a plane like that so have no idea. I've *heard* its like flying on really realy low rates (unless you have one side with servos all locked at full throw)

Some of the guys who fly these big birds beleive in doing a redundant system , with everything doubled up , except the receiver........I don't get it. What happens IF that one receiver goes bad? I does happen on occasion. And when it does.........your plane is going to meet it's doom. My room mate has been flying for over 15 years and just lost a P-51 Mustang dues to a wire that came undone (solder came loose in the receiver) It was about 100' up , and went strait down at about 3/4 throttle......we ended up digging the motor out of the ground with a shovel.


I'm going to have alot more money involved into my new 33% yak , and i (in my own opinion) would want to run the redundant system with TWO receiver's , so that paticular scenerio doesn't happen to me.


I have read a bunch of threads where guys insist that they always run a "dual rceiver" set up on anything on 33% on up.......so i'm just asking for help. I guess i'll try the wiring set up with the receiver #1 does the right side of the plane , and the receiver #2 does the left side of the plane...OR do receiver #1 does , right aileron , left elevator and the receiver #2 does left aileron and right elevator........which do you guys think might be best?


Here is a pic from a couple weeks ago with my room mates P-51.................

Well then you need a backup radio plugged into your radio in case that fails.......


You can't make everything redundant.

Most 33-35% planes

-2 batts
-2 switches
-1 rx
-2 regulators
-maybe a battshare but not needed.


Most 40% planes

-2 batts
-2 switches
-power box
-turbo reg or 2 regulators
1 or 2 rx's

Today's rx's are more reliable than just a few years ago. So really its up to you on how much money you want to spend.

My 35% is done like the one abov
my 40% is going to have the other one with only 1 rx.

You lose a plane you lose a plane......they are all going to go in eventually

Man... don't get frustrated. This single vs. dual RX setup is as controversial as abortion and Darwinism... well, maybe not that controversial, but close.

It really is up to what you are comfortable with.

I've seen guys land planes with 1/2 of the plane working... it's mushy but it's not a problem. The hard part would be if some if the servos didn't go to center (want failsafes set to neutral in a dual RX setup!!!)

As far as crossing the ailerons and elevators... no real proof either way. Mine are crossed, but it just came out neater in the wiring process.

Some guys run a jumper between the 2 RXs... pos and neg wires only, no signal wire. This way, if 1 reg, batt, or switch fails, then the other battery can power the whole plane. You won't know until you check batts between flights. You are basically creating 1 big power bus... just like plugging 2 batts into 1 RX. 1 RX failing shouldn't take down the other... the + and - contacts are simple strips of metal in the RX... nothing more. I haven't decided on this aspect.

I have both of my rudder servos plugged into channel 4... 1 on 1 RX, 1 on the other. They are rigged in an SWB self adjusting rudder tray... no matching required, and if 1 servo locks hard over the other servo can get the rudder back to center. That being said... 2 rudder servos may be overkill in a 33%, though I'm not familiar with your particular plane. My 35% is a good bit bigger than most (bigger than a carden 35%), and the rudder is huge.

Some argue that 2 RXs is 2x the chance of having a failure... then you may or may not get the plane back depending how good you are and how the RX failed. If you have 1 RX and it fails you have a 0% chance. It's all really up to you... which way do you think the stats play? Are you a gambling man?

One arguement for dual RXs is that it eliminates the need for a powerbox/power expander/etc... If you have 4 digis and 1 basic servo on each RX, AND you have 2-3plugs from your REG/batt going to EACH RX (each plug is only good for 3 Amps) then you really have no need for other power systems / expanders / etc... (failure points). My plane flies great without one (8 x 5955s, 1 x 8101, 1 x 525, across 2 RXs).

Look up the Weatronics system... may be the future of the hobby. Best of everything.

Happy deciding!!!

Ditto, all you need is what's stated above and you'll be fine. i've been flying 33% for a couple of year's and that's all i use.

Dude dont lose sleep over it. it's not that hard to set it up. just keep it simple. use the K.I.S.S. method

OK guys........i guess your right. Thanks for all the advice. I have realized that guys who use single receiver's and guys who use double receiver's all have their own reasons for doing so. I have gotten some really good info from this thread. and it's cool reading all the different ways that people can wire up an airplane...WOW!....i didn't realize there was some many different ways to do this.


I'm gonna take all this advice and weigh it out , and go from there. Thanks again to all of you.



I'm sure i'll have a bunch more questions as time goes on.........this is my first real "Giant scale" airplane. Can't wait to fly it , but at the same time , i'm a little freaked out , thinking i might screw something up. Well.........i guess it's the nature of the beast is there becomes an electrical error of some type.



JEFFRO503

I was in your shoes not more than 2 yrs ago when I built my first 35%. I now have two 35% planes and am working on a 42% plane.

You'll get over your fears and learn that its just a bigger version of the .40's you've been flying. Infact they fly easier and land easier so relax and enjoy

HI Again

There is no end to the various levels of backup systems U can have.

For me it comes down to weight / Performance and costs.

Yes U can run dual receivers and I do on my 40% and larger Models. I find receiver failures are infrequent so I choose not to backup that system.

Attaching a setup of my personal 3.3M CARF Yak. I could have even added backup Batteries for the Primary Batteries for that what if scenario U guy's are discussing.

Last is my small workshop where I do final assembly and repairs on these machines. The Extreme Flt Yak up front is 87 inches for size reference.

Ian

There is no such thing as "true redundancy". The closest you will come is to have a second airplane.
With that said, a bunch of extra failsafe stuff will not prevent someone from turning their radio on with the same frequency, or prevent midairs, or the engine from quiting in a hover, or the occasional dumbthumb. So going with a bunch of added "redundancy" equipment may end up as dead weight. Mind you, too, that with all the crashes that I have personally seen, giant scale or not, not a single one of them, in my 20 years of flying was the result of true electronic equipment failure. Sure, you will see planes go dead in the air and find the battery had taken a dump, but it was bad before the plane went into the air and the pilot didn't check the voltage under load right before the flight or he wold have caught it. And receivers have caused crashes, but only because the rx was not mounted properly or was in a previous crash, etc. Basically, most failures are pilot errors. Keep on top of stuff and you won't need all that redundancy weight.
The farthest I have gone is dual batteries with failsafe switches into a single rx. Beyond that, my redundancy comes from regular maintenance and inspection of my equipment. The result is a lighter plane and even less stuff to go wrong.