gregoryshock

In my last thread Ihad a retract problem. link: http://www.rcuniverse.com/forum/m_10...m.htm#10748334

I think that part of that problem is solved!




I've always flown models with just 4 channels. 7 servos at the most! This time, the Corseair is going to have 7 servos and 2 Electric Retracts. I've always flown with a 4.8V 600 mah battery. I'm using a Hitec Laer 6 channel. Do you think Ishould upgrade the RX battery to a 6 volt?

Gray Beard

My Feedback: (-1)

I gave up 4.8 volt years ago except for some ignitions that call for them. I often run two 6 volts for the flight pack if it's a plane I really like. Two batteries and two switches carry some weight but at Batteries Plus I can have the packs made up with high mah AAA, that saves a bunch of weight.
The only time I have ever used anything as small as a 600mah was in race planes that only have a few minutes of air time per race.

gregoryshock

Mr. Gray Beard it sounds like you are into giant scale. How would you put that many on board a 60 size plane? Idon't want to take a chance on burning out the reciever.

Gray Beard

My Feedback: (-1)

Try Gene. I just gave up what I thought of as giant scale and got rid of my big planes. I have stuck with 60 size for years and years and just like them better. I just finished a 1/4 scale though and it has a bunch of room.
I use the packs to CG the plane. I put the plane on the CG machine and tape the packs and servos on the outside of the plane to get the CG. Then I hard mount everything inside the fuse in that location.
The plane I just finished is the 1/4 scale and I had to mount servos and one battery in a set spot. That only leaves me with two battery packs to get the CG with. Depending on the CG will also tell me what size packs to use. AAA, AA or Sub-C. Your only talking two packs. There are two sides of the fuse. Mounting can be Velcro straps, a box they slide into, fiber ties. Let your thought process begin.

gregoryshock

My problem is my electric retracts are having trouble lifting the wheel.  And I only have just 1 retract and no servos hooked up!  The manual to the retracts mentioned that sometimes you need to use a 6 volt battery pack, but you don't need any external batteries to operate them.

Gray Beard

My Feedback: (-1)

Then run a 6 volt pack. They come in all shapes and sizes. I just happen to like the ones I have made for me at Battery Plus. More money but the packs are all made with fresh batteries.

Steve Percifield

My Feedback: (14)

I'm with Gray Beard. I've run 5 cell packs since the late '80s. Remember, if room is at a premium, then you can use 2 500 or 600 mah packs and have 1000mah, 1200mah at your disposal. Just plug the second battery and switch into any unused channel. This also, divides the current load which will allow lower amp draw per battery, giving more useable power in your system.

BTW, just my opinion. But I would not run the retracts from my receiver battery. If the retracts drain the battery, the only thing left is a crash. JMO.

gregoryshock

Steve -  I don't understand how your wire configuration works.  How does it not over power the receiver.  And How do you make the power of one battery pack power the retracts separate from the entire system?

jetmech05

Using 6 volt battery won't hurt your receiver or servos......Now there are some retract servos that won't tolerate 6V...but you said you had electric eretracts so I assuming that you're using electric motors to retract the gear and not servos.....
So some basic electricity here....Voltage in series such as a flashlight were you install batteries positive to negative on top of each other the voltage is additive and the available current remains the same...In a parallel circuit such as two batteries to two different switches 1 switch to the battery port on your receiver and the other battery/switch to any unused channel on the reciever the voltage remains the same and the available current is additive....so in other words two 6V 1100 mAh batteries in parallel will give you 6V and 2200 mAh.....don't worry about the current the receiver will only get what it needs......
With electric retracts I'd go 6V with at least 1100 mAh as a minimum...1500 would be better and remember the current draw if you do touch and go's with the gear cycling....

gregoryshock

jetmech05

That makes sense   Thank you for the information. 

Steve Percifield

My Feedback: (14)

gregoryshock

If you didn't understand what jetmech05 said, I'll do a mock up and post a picture. I don't know how to do drawings here. But don't wory, 2 parallel 6 volt batteries will not harm your equipment.

As far as the retracts go, I'll have to plead ignorance. I don't know how to wire them, even if possible, to run off a separate battery. I know, years ago i had Kraft electric retracts and they had the option of a dedicated battery. I went on Horizon's website and looked at the specs for the retracts. It shows a 800mah draw if stalled. That would drain a battery pretty quickly. So, just make sure they operate without binding and once flying, check them often. And definately use redundant batteries, that will offer some protection.

wish i could be of more help

steve

I fly WW1, so don't have to worry about retracts

jetmech05

I ran a pair of down and locked electric retracts on an airplane.....the retracts were electric motors.....on 6v from the receiver...I used Li-ion battery with a voltage reg to 5.8V...there a several ways to wire retracts

gregoryshock

I've never used a power regulator. And I'm not entirely sure how you guys mean by having 2 switches. I think you mean 1 switch for each battery. The reason I'm not sure, is because some of you are also trying to figure out a way to power the retracts independently from the rest of the system. As far as I can tell, my retracts are not designed to be powered independently from the system. You can find the specs to these here: http://www.wingspanretracts.com/LGR610T

jetmech05

Like I said I didn't run my retracts seperatly.....what is meant by 2 switches is you're running 2 batteries a switch for each...either battery/switch is capable of powering the system but if you lost a battery/switch you lost half your available amps and no way of knowing it.....
So to keep things simple....run a single 2200 to 3000 mAh battery to a switch then the battery port on your receiver......monitor the amp draw of your retract carefully and base your recharge time on that......
Now if you want some back up...then 2 batteries and 2 switches...either way run your retracts through the receiver....just monitor your batteries carefully so you know how much you can fly on a charge

gregoryshock

I think I understand what your saying.  But to make things clear for sure.  I'd need to a see wiring diagram. 

jetmech05

I can't draw a schzmatic on the puter....but on the receiver all the ports for every channel are wired in parallel....in other words all the powers are wired together and all the returns are wired together....only the signal is wired seperatlely....so if you run 2 batteries through their own switches and hook the batteries to any unused ports on your receiver then that is parallel where the voltage remains the same.......two switches with two batteries so you can shut each battery off......
There is one thing I have forgotten to mention...if you use 2 batteries they must be the same voltage and same mAh rating

js3

My Feedback: (3)

Is there any danger or concern about putting a Y harness on the two switches, then plugging into the RX?

Thanks,

jetmech05

Electricly a Y harness would still be in parallel.....However I wouldn't do it....if the Y fails which they do you lost both batteries and your airplane. You'd be better off just running 1 battery pack instead of 2 on a Y to save the weight

Steve Percifield

My Feedback: (14)

http://www.hangtimes.com/parallel_packs.html


go here. much information and should answer all your questions

JohnBuckner

My Feedback: (1)

You still have reduncancy in switchs/batterys by using a Y to plug the two and then into a RX.

What you have done is add an additional component ( the Y) between the battery(s) and the Rx. There is the added possibility of Y failure but that is not huge unless you use excessive length of wiring and or to light a gauge wire on the Y. My preferance if you wanted to do this is solder up my own Y to make sure the minimum wire run and sufficient wire gauge was used.

Actually I have done something similar. The airplane is actually a Seniorita that flys as both a Twin engine and a glider. The battery is positioned in the very tip of the nose or clear back under the stabilizer depending on the configuration of the airplane. A permanent Y is installed to the nose and under the tail of course it is of appropriate gauge and custom soldered. Been working well now for I think about eight years as a hard working twin and aerotow trainer.

John

jaka

Hi!
You should never use your receiver battery for powering the retracts!
Use a separate battery for the retracts and only take the the signal from the receiver! 250mAh NiMH will be fine for driving the retracts

gregoryshock

As far as I can tell, My retracts are made to operate on the system as a whole.  I can see no way of designated one battery to the Receiver and servos.  And Just one battery to the retracts.  It seems to do what Jaka suggests, one would haft to hack into the retracts and totally rewire solder and whatever else.  So that you could just get the signal from the receiver but not the voltage. And get the voltage from an external pack into the retracts without running it through the receiver.  If it were possible, It would void the warranty.

Rob590

There is no need to hack anything in the retracts. They plug into receiver as any normal servo would plug. Here are schematics how it's done. I do not take credits for them Idownloaded them from forum, but I use this system extensively and never had any problem with it.

JohnBuckner

My Feedback: (1)

Jaka my response was to js3 in regards to pluging two batteries directly to the RX. A different question and had nothing to do with retracts.

carrellh

I would not run a separate power supply for the retracts. You can do it (post 23) without hacking up your electrical system or voiding warranties, but, using the "parallel pack" info from http://www.hangtimes.com/parallel_packs.html (copied from post 19) should be all you need.