Thinn

Hello,
I've just converted my Oxalys to 170CDi power.. After a near miss earlier this summer, I've been more aware of the current drain of each flight!
On my Oxalys, I've had a few different set-ups regarding engine/servos.
Currently I'm using JR DS8355 for ailerons/rudder/elevator and a small JR Digi on throttle. I've connected the CDi-unit directly into the RX through a digi-switch.
RX-battery is a Graupner LiFe 1100mAh.

Last time I was out testing, I had 3 flights of approx.8min each. This drained a total of approx.800mAh from the battery! (I charged 800mAh after flying). I thought this was a bit "scary", and a real wake-up call!..
But the major question is: Is it normal? (Using approx.270mAh/flight). If so, I'll have to invest i a slightly larger RX-battery...
(Yes, I know electro is using less than 100mAh/flight, but I'm not there yet!).

As a comparison, using JR DS8401-servos and YS170, I avaraged 110mAh/fligth.

Any thoughts?

rgreen24

My Feedback: (6)

Depending on the schedule you,fly this is very normal. I remember when I flew glow several years ago in Advnced and intermediate, I would easily put 200 mah per flight back,into the battery. You can stay with the smaller battery if you like but charge after every third flight or use a bigger battery. Your servos with glow are always fighting to find center with the vibration of your engine, again, IMHO this is normal, and digital servos are power hungry

rcpattern

My Feedback: (45)

Those numbers are not that far off. With a Hyde mount previously I was using roughly 200-225 mah per flight depending on conditions. I know some guys using the YS mount used slightly more. 275 would certainly be well within the limits of normal for that setup.

Archie

apereira

Hello Thinn,

On my Axiome I consume about 180Mah on the Rx and 86mAh on the CDI battery per flight of 14min.

I use a TP1350mAh for Rx and a TP900mAh for CDI, I usually make 5 flights befeore changing to my second set of bateries.

1100mAh is good for 2 flights for me, as I do not drain the batteries more than 50%, and as you know you can only measure the LiFe when recharging, so not knowing what you have is really scary part in my opinnion.

Regards

Thinn

Thank you for the reassuring answers!
I'm flying F3A P-13, using a stnd Hyde-mount.

I was hoping for a bit less Amp-drain given the smoother running CDi-engine. I've got counter-weights on the ailerons, but I'm guessing the speed etc of the servos require a fair share.

Just found the Graupner LiFe 1600mAh RX-battery weighing the same as the 1100 and similar dim's - Now ordered!
http://www.graupner.de/en/products/0...2/product.aspx

I'm setting up my new model, so I'll pop in a 1600-battery there! Same engine, same servos...

robert

I run serperate receiver and ignition batteries on my model and get almost identical run down between the batteries; roughly 100mah per battery per flight. Ignition is slightly less and receiver is slightly more. The batteries are two 1,100Mah LiFe batteries which easily allows for 6 flights + a nice safety barrier.

BTW I got my packs from http://www.hangtimes.com/ after some communication with them I was able to get a battery that allows for both charging and balancing through one regular futaba DSC port on the side of the model, very easy for rapid field charging as I don't have to take off the wing to get at a balancer connector. Might be useful for someone...

rene69

I fly a Valiant with YS170DZ CDI. I use JR3241s on the elevators, JR 8411s for rudder/ailerons and small digital servo for throtlle. Using a TP1800 Lipo with a Digiswitch with regulator, I fly 3-10' flights when the batteries are recharged they show that about 45 to 50% of the power was used.
So, what I do is 3 flights and replace the battery.

Good luck
Rene Grebe
Texas

MTK

Are you guys using the Tech Aero Ignition Battery Eliminator? This device allows using a common battery for radio and ignition.

I use an 1800ma LiPo in my pattern gas set-ups, powering radio and CDI through the Tech Aero unit. I stop at 75 minutes of flying per charge....voltage reads 7.4 to 7.5 volts after flying, which is nominal voltage for a 2 cell LiPo.

My gas set-up is 2 stroke; so the 4 stroke must be realy banging the control surfaces around....interesting!

bjr_93tz

Not really, if you take another quick look at Apereira's numbers which are pretty close to mine ~250mA for 15 minutes of airtime (cdi+plane) we're both only using up about 1250mAh for 75mins of airtime. I'd fully expect an 1800 Li-po to be still showing nominal voltage with 30% of its capacity remaining.

Everyone's definition of a "flight" is different. For me it's a fair chunk of the 600cc fuel tank down the YS's throat which is about 12-13 minutes of >20% throttle (I don't time the idle). At a comp and for serious practice I only put in 1/3rd tank.

apereira

Another important note is we ussually make lots of corrections if it is windy, on calm days the Rx draw is about 30mAh less.

drac1

My Feedback: (4)

I am running the 170cdi in both my Valiants. LR85 Hyde mount. All servos are JR digitals. 9411 on ailerons, 8511 on rudder, 8231 on elevator (pull/pull) and 362 on throttle. Battery is Duralite Li-Ion 4 cell 4300 (redundancy) pack. This is the same weight as 2 x 1100 Nicads. The ignition draws from the Rx pack through the Aero Tech IBEC.
I can get alot of flights with this set up. The battery loses approximately .07 volts per 8-9 minute flight. I have never had to charge at the field. The only downside is about an extra 100grams for the 4 cell pack, but i can live with that as i have the redundancy in the event of a cell failure. Which hasn't happened yet.