Is it an acceptable practice to
 

have two 7.4 volt batteries ( 1 of 4000 mah and the other of 5600 mah) connected to a smart-fly super regulator then have the reciever leads "Y" to a single lead into the reciever?

Im testing a 7 channel 2.4 reciever on my eurofighter and dont have a separate channel for the other lead so I've decieded to Y them. Is there anything I should be worried about except that I have a single point of failure now?

Thanks

Luis

RE: Is it an acceptable practice to
 

I would Y the second battery lead to one of the other channels, gear, brakes etc.

RE: Is it an acceptable practice to
 

Very cool, I hadnt thought about that Bob-O, Thanks!

Luis

RE: Is it an acceptable practice to
 

In one case I came upon, I Y'd them into the battery channel with leaving one Y open so I could put the bind plug into it any time I wanted, or put a second battery on it.

RE: Is it an acceptable practice to
 

No that is the reason to separate them. It is to just have a separate connector for the second battery in case a connector fails (just like Bob indicated)

RE: Is it an acceptable practice to
 

By joining the regulator outputs to a single lead also defeats the purpose of the Super Regulator. With 2 leads going to the receiver you can double the current. The Super Regulator can handle 7.5 amps continuous while the single battery plug can only handle 3 amps.

RE: Is it an acceptable practice to
 

Hi Luis,

Do the regulators mentioned have diodes in series? A diode is necessary to keep the batteries independent of one another and also ensures the current draw is equal from both packs.

As the others say, creating a single point of dependency is never a good idea. I run two Rx packs with diodes in parallel joining after two HD switches, and then branch off into power for Rx and 3 match boxes. This is still not invincible, but very reliable. Also, you need seperate charge leads to each pack before the diodes (diodes allow one way current).

Hope this helps.

Regards,
Richard

RE: Is it an acceptable practice to
 

This statement is not true in context.

By putting two packs you are halving the current draw necessary from each pack. Whether that is into one port or two does not change what the pack will deliver.

You are doubling available current regardless of one port or two.

RE: Is it an acceptable practice to
 

Thanks alot for the input fellas. I've done what Bob-O suggested and Y'd one of the leads with my brake channel. I'm almost done with re-stuffing now!!!


Luis

RE: Is it an acceptable practice to
 

Having a single power line plugged into a receiver can't deliver as much power as two leads plugged into two ports on the receiver. A single power wire into the receiver can't handle a constant 7.5 amps.

RE: Is it an acceptable practice to
 

I understand what you are saying, you're just wrong.

You are suggesting that the airplane won't run on one battery. IT WILL.

And yes, those wires are rated for more than 7.5 amps. The bus on the receiver is rated for 20 amps.

RE: Is it an acceptable practice to
 

I never said it wouldn't run on one battery.

The connector that plugs into the receiver is not rated for 7.5 amps, yes the bus on the receiver is safe upto 20 amps.

RE: Is it an acceptable practice to
 

Prove it, I will apologize if you can.

So now it's the connector and not the wire. I and others have run load tests on this equipment, and think about this for a second. If the bus is rated for 20 amps, how would anyone get 20 amps to the bus?

22 guage wire is rated for just over 7 amps.

My battery systems are 20 gauge or better.

Oh, and a quick search on Google found me this chart:

http://www.powerstream.com/Wire_Size.htm

What I can't figure out is why you continue to make the above claim without sitting back, taking a minute and looking up the information you are claiming. We're not talking a .40 size trainer here are we? Cause if we are, you are right, a ten dollar 4.8 volt pack, might eat itself up trying to handle the load of 6 digital servos in a split S at 200 MPH. Wait, a .40 size trainer won't do that.

RE: Is it an acceptable practice to
 

I was always referring to the connector (J plug). In my first post I say plug not wire. My information comes from Bob Ritchey, the owner of Smart-Fly. I have no reason not to believe him. I also was saying continous amp draw not spikes.

I am not sure why I would be talking about a 4.8 volt cheap battery when we are discussing the Super Regulator.

RE: Is it an acceptable practice to
 

I know Bob, and this must be a sales Tactic, because we've run 10 amps through these connectors seeing how hot we can make a Regulator go to see it fail.

RE: Is it an acceptable practice to
 

He is meeting me out at our field this morning. I will talk with him about this. I am not a EE he is. I am the idiot that makes sure it is idiot proof. I am just the guy that test flies all the equipment before it goes into production.

How hot can you make the transititor before it fails? Which regulator?

RE: Is it an acceptable practice to
 

We tested the Duralites and MPI to 8amps and the smart fly to 10.

ya, gets really hot, and the connectors don't fail.

RE: Is it an acceptable practice to
 

By the way, the smart fly regulator is the best regulator we have tested. The likely hood of one of our jets ever getting to even 7amps sustained for more than 5 seconds is not very likely. Most of my jets fly on one battery, one switch, and one duralite or MPI regulator.

I have never had a glitch, but I make sure there is no binding on any of my control surfaces with an amp meter on every jet.

It is well known that I am a full throttle pull hard in the turns kind of guy. If there was going to be a connector failure, or battery problem, I would have found it in the last thousand flights.

Also, I fly all 2.4 in four jets. Never had a receiver reboot.

In my lightning, I did go to two batteries as there was one control surface I could not get to do what I wanted without it sitting neutral at half an amp. I didn't want to keep half an amp draw on one battery and when I added the second, physics worked and cut the draw in half.

RE: Is it an acceptable practice to
 

Have you used any on board Data logging to see how many amps you are pulling?

RE: Is it an acceptable practice to
 

When you were testing the plug at 10 amps, were you recording the voltage drop at the amp draw source?

RE: Is it an acceptable practice to
 

I have tested the weatronics in the lightning. But that's a totally different animal, two battery systems etc.

To answer your question, in the building of 20 plus jets, the only verifiable model turbine jet that you see at jet rallies/ commercially available, run of the mill turbine jet that requires anything other than a single battery single switch, and duralite or equal regulator is the BV F-100.

There is a lot of misconception about the setup of these jets and how to properly set up throw while using an amp meter. When you setup with an amp meter and you go to full deflection, often times you will see a one amp load at say 100% travel, but a half amp load at 94% travel.

Aerodynamically, the airplane is going to fly the same, but from an electrical perspective, there is a major difference.

Look, I'm getting bored talking about this, I have been through this numerous times in this forum and others.

I have run plenty of tests to feel comfortable with how I'm setting airplanes up.

But I'm telling you, that at a minimum even the cheapest of our connectors are rated no problem for over 7 amps. And I still welcome you to prove me wrong. Why not go post this in the JR forum "ask danny"?

Or keep on doing what you're doing. I have been preaching proper setup of these airplanes electrically for about three years or more (when using li ion). The guys at Florida that changed over to 2.4 from PCM learned a hard lesson by not testing their systems load with an amp meter before they flew (at least that's what I've been told).

On a Nicad system, this isn't going to matter, the battery will keep feeding whatever the system needs till it bleeds all over itself.

RE: Is it an acceptable practice to
 

The highest current draw comes from the movement from point a to point b, not holding full deflection.

I asked Bob, he said at 3 amps the J plug is heating up after 2 minutes.

RE: Is it an acceptable practice to
 

"heating up" You have to get to 150 degrees F before the plastic even starts to get soft. And if you are holding that kind of amperage for that long, you're not in a jet application, or you have set something up incorrectly.

Regardless, the indication was holding up under 7amps, and they do.