Anybody using a dual power supply for the RX

[tomskk]

Hy, is anybody using a dual power supply for the receiver. I'm looking for a plan to make myself a safer dual power receiver supply. I'll be happy for any comments.

[Mr.RC-CAM]

Red has some info on his site for a simple reliable implementation: http://www.rcbatteryclinic.com/parallel.html

[Comatose]

You mean a dual BEC or dual batteries? Dual BEC is easy - buy two ParkBECs, plug one in normally and one into an extra channel. Boom, redundant BEC. ParkBECs can be paralleled.

If you want a more DIY linear solution, then the trick is finding linear regulators that will source current only. If the regulators source only and have a negative temperature coefficient (voltage output goes down as temperature rises) then you can run two in parallel without any complications.

Battery packs can just be thrown in parallel. Just don't charge them that way if they're NiMH or NiCd.

[tomskk]

Thanks for your help, but I was more into dual receiver supply for a large glow plane. I would like to eliminate the possible problem of a mechanical switch and exchange it with an electronic switch.

The direct connection of 2 receiver batteries on a receiver isn't any garantie for safety. I was thinking more of a PIC MCU based dual battery supply. When one battery drops below minimum or has a problem the PIC MCU switches to the second battery and supply the receiver from the second source.

Does anybody have any ideas on how to implement that?

[Acetronics]

Hi, Tomskk

Does this sound good to you, despite there's no processor ???

Alain

[tomskk]

Thanks Acetronics, something like that, but with less complexity and maybe a bit smaller. What is the rated input voltage on your design? What is the approx. cost of the your design? Can you explain to me in which way this system works?

[vintage1]

Unless you have actually done statistical analysis on failure modes of batteries and opic based switches, you cannot possibly assert that the extra complexity of an elecrtronic switch is superior to two batteries wired in parallel.

Two diodes achieve the same efect, but as Red showed, are unnecessary.

An active switch is only superior in that it can cope with a fully shorted pack. However it will need a third battery to power it.

A fully shorted pack is likely to be an inflight fire anyway, regardless of the integrity of the receiver supplies :D

[Acetronics]

Thanks Acetronics, something like that, but with less complexity and maybe a bit smaller.
> you can be dreaming for less complexity, you deal here with some real power, as I've read ... cms would make it smaller, yes !!!

What is the rated input voltage on your design?
> it accepts 2 x 4 to 5 Ni Cd cells ...

What is the approx. cost of the your design?
> The price you can pay for you plane's sake ... let's say around 100$

Can you explain to me in which way this system works?
> You're asking, as we say here, for the butter, the money for the butter, and the smile of the dairywomen ...

let's say the two batts are really parallelled, and if there's a problem with one, it's unconnected in µseconds ...
after that, a 5.5v regulator is implemented for digital servos.



Note for the same amount, two LDO's and two Schottky power diodes do the same ... but with this damn current limitation !!!

a µP design has a big problem ... steady current drain !!!

Alain

[birdofplay]

So from the above, I gather that redundant batteries is kinda silly.
Given that most of us have never had a battery problem.

SO the real need is simply for better power distribution.

Looking at the prices for those kinds of products I got a little INCENSED.

So I layed out a board using Xpresspcb ( free sw) on their std board size
and Wah Lah - I think I have a reasonable way to go at a reasonable cost.

Thoughts anyone ?

[prosa]

Acetronics
Do you have the PCB drawing for your COUPREG2. I would be very apreciated.
Merci Beaucoup
Pedro
Portugal