RE: Is it Electric really worth the trouble ?
 

Hi John,

One other thing you need to account for with electric is the cost of electricity to charge the batteries and or the cost of a mains generator and DC power supply.

Cheers
Jason.

RE: Is it Electric really worth the trouble ?
 

Staying a few hours away from the TV or computer (building and flying) will compensate for the power consumption quite nicely :p

RE: Is it Electric really worth the trouble ?
 

Jason

I did factor in the DC power supply unit at £40 and I already had two big leisure batteries for field charging, mains electricity? I can't be bothered to do that calculation but I am sure it is still cheaper to buy and charge the lipos than buy high nitro fuel.

regards

John

RE: Is it Electric really worth the trouble ?
 

G'day John,

I noticed you had allowed 40 pounds for a Power Supply in your post after replying to you:D. I bought myself a switchmode powersupply and it cost me about twice the price yours did but it is a nicely packaged unit and can supply 25A @ 13.8VDC.

At most comps I attend, people bring their own generators for charging batteries. Personally, I use a 2Kw Honda(20i) generator but it's also used to power our house when we have a black out. The small Honda 10i is more than adequate for charging our batteries though and costs less to buy. There are some cheap generators on the market but none come close to the Honda for quietness, efficiency and reliability. A deep cycle 12 battery is also another power source option. You'll have to buy the battery which won't be cheap and also a suitable charger.

Cheers
Jason.

RE: Is it Electric really worth the trouble ?
 

Jason

As posted above I already had two big deep discharge batteries for starting my turbines so no additional cost was involved in that. My Cellpro 10S does an excellent job of charging these !

regards

John

RE: Is it Electric really worth the trouble ?
 

John,

I realise that but we are talking about someone starting up in electric.... A new person to electric may need to also allow for a power source of some kind.

Cheers
Jason.

RE: Is it Electric really worth the trouble ?
 

Jason

Ok, the beginner needs to add £60 to his budget for a deep discharge battery. BTW I have just ordered some more Rhino Lipos from HobbyKing. 3700 5S 20C @ £45 and 3700 6S 25C @ £50 including air shipping to the UK, seriously cheap Lipos.

regards

John

RE: Is it Electric really worth the trouble ?
 

Just to add one comment.
If you use A123 batteries the cost of batteries goes way down as they last for up to 1000 cycles and you can get them from EBAY for about $7/cell

RE: Is it Electric really worth the trouble ?
 

yes, cycle life on A123s is longer, however, the energy density is still pretty poor compared to lipos. You need to run a 12S A123 setup to get close to a 10s setup with lipos. Overall weight of a competitive A123 pack is quite a bit more than equivalent lipo.

But you can fast charge A123s and pretty much abuse them discharging and they keep on ticking......

Woodie

RE: Is it Electric really worth the trouble ?
 

A 12s2p A123 pack would weigh 1lb more than an equivalent lipo pack. Is that quite a bit more for the size A/C they would go in? The cost on ebay is $144. It would take you about three years to wear them out if you averaged 1 flt/day.
The cost of 2ea 5cell 5000ma lipo packs is $380 listed on ALLeRC for less than 1 year if you baby the packs and average 1 flt/day.

RE: Is it Electric really worth the trouble ?
 

I agree the A123s are robust and cost per flight is attractive, however, when you have to push an 11 lb pattern plane to 12 lb just to get longer lasting batteries, it kinda defeats the purpose. With a limit of 11 lb for any serious competition, you don't see any A123s being used.

Having said that, if you don't care about the extra pound, go for it. Maybe someone will figure a way to make our 2M planes a pound lighter and then they would be great.

Woodie

BTW, the Hyperion batteries (25C) are $160 a stick or $320 a pack, not $380. And the new G3 technology seems to be lasting quite a bit longer than previous generation batteries. Don't know how long they will last yet. My sets have about 75 cycles on them and the IR has not changed at all. Hope it stays that way.

RE: Is it Electric really worth the trouble ?
 

Woodie ... please enlighten me, what is a good range for the IR? What would be deemed almost terminal? :)

RE: Is it Electric really worth the trouble ?
 

well, it depends........... don't you just hate that term?

All the following IR values were taken with the cells at about 75 degrees using the same FMA Cellpro 10S charger. The packs were charged at 1C as a 10S set. The IR will increase as the packs are colder and decrease if they are warmer. These are my experiences and others may have different results. in other words, YMMV

For my TP 5300 V2 Prolites at 75F, somewhere around a 3 mohm per cell is typical and it is a 20C battery. I only have about 70 flights on these and the IR has increased about .4 - .5 mohm per cell average with a +- .3 mohm variance. The packs perform very well and are good steady power during flight. I notice minimal drop off toward the end of a flight and pack temps seldom exceed 110F.

I have a set of FP 5350 with less than 70 cycles on them and the IR is above 7 mohm per cell on average with as much as 2.5 mohm variance. These packs are 'done' and are the worst I have had so far. Even worse than a couple cheapo chinese packs I tried. My oldest TP 5300 5S4p packs with over 250 flights on them have an IR that is less than the FP 5350s with 70 cycles and the variance is around .5 mohm. They will still get me thru a P-09 schedule but it is pretty draggy near the end and the packs are pretty toasty.

My Hyperion G3 5000s (25C) started out around 2.1 mohm per cell with a +- .2mohm variance. After the first 1-12 cycles, they have remained basically the same. In fact, they improved slightly at around 12 cycles. These cells are pretty impressive so far. Packs will warm about 20 degrees during a typical flight.

For a 20C pack, my guess is they will be 'done' at around 6-7, maybe 8 mohm per cell maybe a little less for a 25C pack.

As the lipo batteries have improved, our expectations of them have also increased so what we considered OK a year or so ago is pretty poor performance with today's newer lipos. It will be very interesting to see what the next couple years holds for the lipo world.

I am pretty careful with my packs and hardly ever take 80% out during a flight. Typical recharge for a P-09 flight is 32-3300 mah. I am usually at 68-70A or less during a flight unless it is windy and then I might hit 73-74A for a brief period. I charge at 1C and each packs gets at least 5 easy flights on them prior to being 'put to work'. I don't know if this break in approach helps battery life, but that's the way I do it.

Woodie

RE: Is it Electric really worth the trouble ?
 

Woodie ... IR reading is taken after its fully charged, noted. :) Thanks!

RE: Is it Electric really worth the trouble ?
 

Yes, all IR readings are at full charge. The IR will go down very gradually during the charge cycle.

I meant to include a link to the www.electric-F3A.com site in my previous post but forgot to insert it into the post. The site started by Chris Moon has a lot of 'e' info on it including battery performance data like IR, amps and battery life stats. You might want to check out his site for info on batteries and motors. Sorry I didn't include it in my post initially.

Woodie

RE: Is it Electric really worth the trouble ?
 

Thanks woodie!

RE: Is it Electric really worth the trouble ?
 

Hello, I have been in R/C for over 30 years. When I started, nitro was the only real option and I owned a lot of different planes that we nitro powered and enjoyed the sport. 2 years ago I decided to get back into the sport and I decided to give electric a try. I had tried electric back when nicad and NIMH were the power sources of choice and I was pretty disappointed but Li-poly changed all of that. Now all of my planes from my light indoor planes to my 74" 12+ lb. planes are all electric and the reasons are simple. In comparison to nitro, electric is now much more reliable and there is no clean up. I will often arrive at the field well after other club members but I usually get a flight or two in before the others because there is just less fiddling. I have several models now with 300+ flights and 0 dead sticks and especially when 3D flying inches off the ground, this inspires the confidence needed to try things that I just would not consider with a nirto model. My flight times are potentially less than the nitro planes but in reality I almost almost always end up with more fight time overall due to less fiddling and no clean up. I love the instant power on of electric. My 74" Yak comes in at about .50 per flight depending on the batteries I am using which is cheap but ther is a big upfront cost that you don't have with nitro or gas and that is a downside. Electric motors and batteries are good at providing lots of instant power for short durations when you need it, such as when you suddenly realize that you need to do a go around or when you are in a hover 6" off the ground and suddenly your plane torque rolls and is just off the ground inverted. And electric is only getting better with the improved bateries. For the larger planes say 90" and up, it really gets to be too expensive for me to consider electric at this time but I think that it won't be long before this changes. So I have owned and flown both and I cannot imagine ownring anything except electric for the planes that I own from 74" and down. Now the EF 110" Yak I have been considering would have to be gas..but I haven't ordered it just yet either! The most important thing is to have fun in the sport so if you are doing that, then you are doing the right thing for YOU.

I would like to add one thing more to those considering flying or just being around large electric models..beware! With a gas or nitro model the noise and spinning prop are a clear warning to be cautious but an armed electric model is actually even more dangerous potentially because unlike a gas or nitro engine and electric motor will not quit if it strikes the ground or yourself,,it won't quit until the solder joints melt away or some electrical component gives up. The armed electric model sits there quiet and motionless until someone accidently hits the throttle stick, there is a glitch etc. Do NOT walk in front of an armed electric model and if you are the pilot, do NOT arm the model until you are ready to fly and keep the model pointed away from people at all times after it is armed. I have not had any incidents personally so far but know friends who have. Have fun but respect electrics, they can slice and dice on a moments notice...

Have fun,

James

RE: Is it Electric really worth the trouble ?
 

 One thing the glow guys will never have is Nuclear Power, which is coming to a field near you one day.  Perpetual flying!  LOL!

http://munews.missouri.edu/news-rele...clear-battery/

RE: Is it Electric really worth the trouble ?
 

I was asking my pattern coach about electric, and he figured that with either glow or electric, the cost is about $2.00 per flight. Batteries don't last forever.

I am in the process of making the switch to electric.

This year I tried my hand at a YS engine. I absolutely loved the engine when it ran right; I got used to the immediate throttle response and near instantaneous power. It started to lose interest in 2 strokes for that reason. However this year brought me more engine troubles than flight practice. Add to that the cost of fuel and the fact that I have to drive 4 hours each way to buy it, the mess I've made in my apartment and the oil stains in my car, and the fact that there are really nice fields which are 'electric only' that I have not been able to fly at.

Electric seems to make the most sense for me. Maybe not for others, but there are few, if any, people who convert from electric to glow.