Battery size for Raptor50? er, high current draw?

[peetrak]

I'm just getting my Raptor 50V2 going and was running my first tank in the driveway to tune my OS50.
I have a Hobbico LED battery status monitor and noticed that during the first tank, my LED's were already showing yellow/red during moderate to medium idles. My pack is a 4.8V AA2500mAh NiMH (balanced perfectly on the shaft). Yes, my pack was charged.
I hooked up an amp meter to the battery, averaging 500-600mAh, but was able to draw between 800-900mAh of load when I move the sticks constantly with only the servos (no rotor load), so I am guessing I could be well over an amp during flight if I suddenly need a lot of collective correction.
I realize that I won't always be using this much, but it's nice to know I'm not going to melt through something, like the small servo wires. I think they're 22-gauge, which is designed for almost 1-amp of power transmission.
So, my question is...What size batteries are you guys running?
Is anybody else having any issues with battery life?
I'm running DS811's, along with a Futaba 9254 on the tail, a Futaba 401 gyro and an Airtronic's blue cube 7-channel rx, JR 9303 tx.
I know the DS811's are on the lighter side of torque, but I had to try and save $$ somewhere.
I'm going to try and hover tomorrow, then discharge to check capacity and hopefully gain some confidence in this pack, or find out that I'm just asking too much from a 2500 AA pack.

Any ideas and comments are appreciated.

[Krypty]

This is more of a comment than anything else...... more information is always better :D

I also have the 50V2 (OS50Hyper) with DS811 all round and GY401 with 9254 on the tail. I also have a Throttle Jockey Pro. I run the normal 1100 NiCD that came with my JR9x and I get 3-4 full flights (not hard 3D, only loops, rolls, inverted hovering etc.) before charging.

[porsche]

I use a 1400 ma battery with all 811's and I fly hard, not real hard 3D but hard arobatics and I get an easy 4-5 flights before charging. I would make sure your batteries are FULLY charged before flights, test them after the first flight and see what they read. Don't rule out mabe a bad pack ? In any event to take chances with low batteries. Alan

[Bayou Talker]

Did you check the voltage with a loaded voltmeter or just the lights? Could just be that the LED monitor is bad instead of the pack.

I use a 1500 mah Nicad and I can fly for 4 flights without charging with Futaba 3151's and 9254.

[racingstripe]

I would not use 'AA' 2500mAh NiMH cells with digital servos.

Most, but not all NiMH cells have a high internal resistance... So as the current draw increases, voltage decreases.

If you prefer NiMH... Sanyo has a number of "high-rate discharge" NiMH cells. Try finding a pack that uses a Sanyo HR-4/5FAUP cell.

andy-

[bighands3d]

Those meters are not all ways correct your best bet is a load tester from MAH blades or Radio South.

I would recomend a 1400-1800 sub c nicad pack you need the voltage and amperage for an all digital setup. NIMH batts have been used in the past an have not done well on helis. If you really want some flight time go Lith Ion, MAH sells a complete set up, I use it in all my helis but mine are 60-70 size. with hard 3D you get 9-11 flights I get about 12mins per flight.

http://www.mahblades.com/product_info.php?cPath=99_100_102&products_id=41

[graham39qld]

I am also flying a 50v2 with JRDS559 servo's and a G6000T wih 8000G SX tail servo, I have been doing pretty well with the 1100 RX pack that came with the JR9X2, about three tanks full form that battery while running in a new OS50Hyper and learning to hover. not to bad considering the Heli is on the table having ajustments all the time with the battery feeding the tail servo that has an over active Gain causing me trouble, hopefully I will learn how to set it up soon.

I have purchased from EBAY a Sanyo 3600mah C cell 4.8v pack for Aud$38.99 and I am going to give that a go soon, that should be heaps of power, apparently the C Cells can handle a much bigger load than the AA's and last for ages, and they fit fine. you can buy 2 on ebay for AUD$93.00.

I will let you know how it goes.

Have fun, cheers

Graham

[ausheli]

hey Graham did you buy that pack from Alex at Double L trading, he builds great quality packs and I am using those same packs in all my helis with no probs

[graham39qld]

Hi Ausheli

Yes I bought them from Alex at Double L Trading on Ebay

Great price and good to deal with, I am using one of his 2500 packs with the C Cells at the moment, I have been very fortunate to loan one for now, and it is fantastic, hopefully should have the new 3600 pack next week.

My order was 1 x Sanyo 3600 c cell pack with Jr Connector and dean plug.
1 x TX pack Sanyo 2500 for JR, 2 x male and female dean plugs for spares etc. plus some shrink wrap.

Total $AUD 104.00 that included postage via Registered Post within Aust.

I thought that was pretty good :)

I am off to the field for another day of out of control hovering and bumpy landings again tomorrow, but I cant wait, I am totally hooked now, my poor Hyper Raptor 50v2 couldn't have had a worse pilot for an owner lol, but ya gotta start somewhere I guess.


Happy flying Heli Freaks, have fun, Happy New Year

Graham

[WillJames]

Keep at it Graham, your Raptor will be doing more than hovering pretty soon if you stay at it. Everybody has to start somewhere.

[tnreefguy]

I would get rid of the AA bats. The general rule with NiMh is not to run any cell in the machine smaller than a sub c. For your fifty I would look at a li-ion setup with a regulator. Lots of forums on the topic here. Have fun and good luck.

[playfair]

Ditto not to use AA NiMh- they have a really high internal resistance, which means that voltage drops when current is drawn.

You don't have to go to subC either if you don't want the weight; there are readilly available packs from Expert/Horizon that use A or subA (4/5A as an example) cells which are also high discharge. They will have a smaller capacity then your AA's, but you will get more flights as there is greater usable energy at our loads.

Of course LiPo is great, running a 2S pack with a linear regulator, or 3S with a switching reg. I get a minimum of 10 flights from my Ubec setup, and only pull 1800ma from the 3S battery.

[DebianDog]

Ditto not to use AA NiMh- they have a really high internal resistance, which means that voltage drops when current is drawn.

That is one I learned the HARD WAY

Hovered fine for many many flights. Then when I went into FF on a windy day at the field and started working the digital tail WHAM! :arggg:

That was the day I switch to Duralights :lol: