Uawflyer

Hey there! I have had a couple of time where the ESC cut out and am thinking about setting up with a receiver pack so that if that happens I still have control surfaces. Just want to ask and make for sure that this will not fry anything before I start setting things up. Thanks for the info!!!

JetPlaneFlyer

A receiver pack is ok, you need to get a battery with the correct voltage for your receiver and servos, such as a 4.8v NiCd pack. The battery plugs into the 'battery' connector in the Rx, the ESC plugs into the throttle connector, but it's very important that if the ESC has a built in BEC that you disconnect the red wire from the plug.. otherwise you might well blow something up

Of course the alternative is a stand alone BEC (aka UBEC) powered from your main flight battery.

Steve

pd1

The drawback with a separate receiver pack is weight.
That said I use a separate pack on all my larger planes, larger digital servos can draw a lot.
I don't have to worry about Spektrum graying out with a receiver pack.

One extra advantage is when using a receiver pack you also use a switch.
When the switch is off, it's harder to get an unintended motor start.
That's a good thing with the larger motors.

Paul

kyleservicetech

This type of thing is fairly easy to set up. Problem is it does add a few ounces of weight, specifically about 5 ounces if you use two 2300 Mah "A123" cells. An option would be to use two 1100 A123 cells for a smaller model. The 1100 Mah A123 cells will weigh about 3 ounces.

One very good source for the 2300 Mah A123 cells is http://www.voltmanbatteries.com/serv...1-dsh-A/Detail. Both many club members and I have ordered about 100 cells from this company, with zero issues or problems. (And they are located in Ohio!)

I've been using this setup on three different models with a combined total of near 200 flights. Also designed an on board voltage monitor that records if the receiver voltage ever drops 6.0 Volts DC. During those 200 flights this spring, I did note several flights where the recorded voltage dropped to 5.4 Volts DC. That was traced to a Castle Creations 10 Amp uBEC whose programmed 6.6 Volt DC output voltage dropped to 5.4 Volts DC at a 10 Amp load. The CC uBEC was replaced.

This setup will work with either the CC 10 amp uBEC or the CC ICE series of ESC's.

Take a look at the wattflyer thread that shows how this was done.
http://www.wattflyer.com/forums/showthread.php?t=63794

Note Dennys battery undervoltage alarm. The "PicChip" measures voltage some 4000 times per second, and if the volts drops below 6.0 volts DC, it displays just how low the voltage dropped by flashing the LED in a code. (The PicChip needs to be programmed with the proper software) If anyone is interested, I could put together a kit for this alarm. It would require ordering more circuit boards though, and that would be a fixed cost of $65. Cost per unit is something like $10. I've built 16 of these things so far.

It simply plugs into an unused servo channel, and weighs in at a fraction of an ounce.

pmullen503

A separate switching UBEC is another option. If your ESC overheats and shuts down the UBEC still powers the radio and servos. (Disconnect the ESC's red wire). Lighter than a receiver pack and you don't have to remember to charge it.

kyleservicetech

Yup
That's what I've got in my 1.5 KW and smaller models. A separate Castle Creations 10 amp uBEC. Been using them for five years, all work well.

dahawk

+1 on the UBEC. Have one in a twin edf and it's great,especially, if you have alot of servos, retracts, etc. Can get 5v/5a ubec's for fairly cheap. Castle is a good one . I bought one from BH for about $7.00 . HK has them as well. Here's a link to the International warehouse but they might have them in the US warehouse. Easy to install.

http://www.hobbyking.com/hobbyking/s...dProduct=18789