TLH101

My Feedback: (90)

What are the advantages and/or disadvantages of 6volt flight pack & 4.8 volt flight pack. I realize that I will gain speed and torque, but I am more interested in the other aspects as I am not doing 3-D. I have both and am looking for other characteristics I may not know about.
I am sure others would be interested as well.

3DFanatic

My Feedback: (5)

Speed and torque go up, run time goes down. I use 5cell packs in everything.

Icebird

Only downside I can really see is that apparently servo life is reduced when using 6 volts. Now, I don't know about you, but I haven't worn out that many servos in my years of flying. I have broken quite a few, but other than cases wearing, causing the output shaft to get a little slop, I can't remember one that I wore out. Ball bearings on the output shaft will eliminate the only wear problem I've ever had, so I really don't see any reason not to run the higher voltage.

YMMV
Jim

JoeAirPort

My Feedback: (41)

IMO, no con's. I can't go back to 4.8, too slow. Also just increase the Mah by 25% to get the same run time as your 4.8 pack.

Tired Old Man

My Feedback: (1)

Just about all the current servos on the market from the major manufacturers used for regular sport flying can be run on 6 volts, with the exception of some of the smaller servo sizes. To be certain, one should always check the manufacturers performance specifications for the particular servo.

Pros:

The non digital, or analog servos, will gain an increase in the neutral holding power at 6v over 4.8. This is good for all types of flying. It will help to some extent in the prevention of flutter. It will also increase the speed at which the same servo reaches a given point, permitting an increase in your ability to fly a manuever more precisely. It makes you look better. Some servos will have better centering, allowing a more consistant return to neutral positions. Again, making you look better.

If the servo gains in both speed and torque, it will have better performance values in all areas of it's travel. A stronger servo will hold the control surface better at maximum deflection, preventing surface blow back that will sometimes override a servo and strip nylon gears.

Digital servos will have similar benefits with higher gains, but at a much higher price.

Cons:

A 6 volt battery weighs and cost a little more than a 4.8 volt. If you need nose weight, the 6v may give usuable help here.

An equal mlliamp rated 6 volt battery will last about 25 to 30% less time than a 4.8 volt battery. I compare it to using the next larger size water hose with the same amount of water. One flows faster than the other.

If you are a person that installs the minimum sized servo in an aircraft, you may want to consider a 6 volt battery. If you usually install servos with greater ability than the aircraft requires, then 4.8 volts would likely be enough. It's better to use over rated servos than to use under rated servos. Cheap insurance.

Jorgele

Hello
Someone have experience working with Futaba Digital 9552 with 5 cell Pack, is it Posible? 5 Cell will damage the servo?

Thanks

Jorge lozano

basmntdweller

My Feedback: (9)

Jorge,
If you meant to type futaba 9252 then yes it can be done okay. I have not personally done it but, I had talked to Chip Hyde when I was planning on buying one of his Cap 10X's and he said he ran the 9252 on 5 cell packs all the time. I think his post is here on RCU somewhere if you wish to see it. It would take me a while to find it though.
Later,,,Matt

It was easier to find than I thought. Here's the link assuming I did it right! His comment is in post #9.

http://www.rcuniverse.com/forum/m_15...tm.htm#1529895

rfw1953

My Feedback: (2)

I'm glad I found this thread and have a questions thats related. I too am considering going with a 6volt 1100 NiCd pack in a Gene Soucy Extra with Hitec 635 servos. I will be using a Futaba FP-R 148DF 8 channel PPM Rx with a Super 8 Tx. My question is this. What are the advantages and disadvantages of using a voltage regulator and is it necessary to use one when not using digital servos? At this time I do not plan to use a regulator, but would sure like to feel confident with this decision.

Thanks kindly for your help on this.

Geistware

My Feedback: (16)

This from Radical RC.

Here is an email that answers most peoples questions who are considering a 5 cell pack.

<< Dave,

One last question, then I will be sending you an order to upgrade my
batteries:>>

These are good questions and will make my web site.

<< What is the difference between 4.8 and 6 volt receiver batteries besides
weight?>>

A 6 volt pack allows some additional safety as one cell can short and you still have enough voltage to keep flying. That is not to say that any type of cell failure is covered if you use 6 volts. A cell can always open up and not amount of voltage is going to help you then. The extra voltage will give your servos more speed and more torque. The increased speed will give your airplane a feeling of crisper roll damping. Flying time will be slightly reduced with a 6V pack over the exact same capacity 4.8V pack. This is a minor reduction and should not enter into any typical battery choice decision.

<< My Futaba manual says that the receiver will use both
voltages. >>

Yes, as it is made to accept 4 Alkalines which is 6 volts.

<< What, if any, performance increase will the 6 volt battery
give? What specifically will increase (better reception (whatever that
means)? less interference? faster servo travel velocity?, etc.?).

Thanks,
David H. >>

More torque. and more holding power. Torque will typically increases more than 25% and of course, faster rotation speeds. The speed back to center is the part you might see the most in your flying. I have heard it argued (by those who are more knowledgeable than I) that many receivers have more range and are slightly narrower band with more voltage.

You will occasionally have a jittery servos when you first turn on a freshly charged 6V pack. This usually goes away in just a few seconds. The peak voltage of a fully charged 6V pack is well over 7 volts. But, it settles down quickly.

For most of my smaller and normal sized ships, I am chasing weight savings and use 4.8V. I do use 6V on a combat model and would use it on any large model (or twin packs/twin switch harness setup) as I like redundancy in ships that are more important to me. There are many different views on this subject and you will probably get 5 different ones if you as 5 different people.

About 90% of all packs in use are 4.8V. 4.8V is fine. If you are searching for extra torque, more speed or need some redundancy, 6V is a good choice.

Happy Flying!
Dave Thacker, www.radicalrc.com

Ross Kean

One more question on the 6V pack...

Will most wall-wart chargers that come with radios charge a 6V pack to capacity? I assume that the charger will put out a little less current charging the battery to the higher voltage level so the charge may take a little longer? Will the wall-wart actually put out a high enough voltage to push any current through the pack - if the max voltage of the charger is anything less than 7 or 8 volts on the Rx side, I doubt it would be very effective. (Wall-warts aren't very smart)

Ross

rfw1953

My Feedback: (2)

Miles, the email and the site attachment info was very helpful, but I don;t see anything about voltage regulators. Any thoughts?

ChuckAuger

My Feedback: (12)

If you run a 5 cell NiMh or Nicad pack, you don't need a regulator. If you run a Lithium ion like the Powerflite, Duralite, etc. you will need to get one. FWIW I run the 148DF on 5 cell Nimh without a regulator on a few different planes, no troubles.

rfw1953

My Feedback: (2)

Thats Jeff!

I think I will stick with my original thought and not go with a regulator.

Man, this NiMh vs. NiCd debate has been going on for a long time. I have been tempted to make the switch, but, (always a but) just don't have the confidence to go there yet. We have had a few guys use them and had failures as well. I guess anything can fail, but it just seems that the ole NiCd is still the battery type used by so many in the hobby. They just seem so durable and proven with time. Maybe it's just a reluctance to change and nothing more to it. I honestly don't know. Hm..............

ChuckAuger

My Feedback: (12)

Oh I still use Nicads! I just don't have any 5 cell Nicads, but sure wouldn't hesitate to use 5 cell nicads.

TLH101

My Feedback: (90)

If you do decide to run 6V, be sure to label your aircraft. Have seen 2 guys forget they had 6v packs and when the batteries checked OK on 4.8, they had problems about 1/2 way into the flight. A 6v pack will drop off the scale around 5.2-5.4v very fast. I have been known to check mine thinking they were 4.8v. So far, I have always remembered. I now mark a small "6V" next to the charge jack.

rfw1953

My Feedback: (2)

Terry, man, I didn't know that. On NiCd's I always stop flying if my tester reads 4.8 volts. I would have potentially walked off the cliff thinking I was ok had I used this same guideline with a 6 volt pack. So, with a 5 cell 6 volt NiCd pack, at what point do you guys stop flying? I want a margin of safety as I have using a 4.8 volt pack reading 4.8 volts as a recharge point.

flycatch

My Feedback: (26)

Question to posters who have said that 6V packs don't last as long as 4.8V packs. Does this apply to NICAD packs only. I have been using 6V NIMH packs and the opposite had been true.
Am I wrong? If so, please provide me with further insight.

ParticleMan

My Feedback: (24)

I use 6v on all my planes, and using the same logic as 4.8v cells I never fly below 6v.


About this regulator business, I've never run one, nobody I know has either. A majority of the people I fly with use 6v. Biggest concern I would see is if you have a freshly charged pack, it can read over 7v easily. I've never even experienced the so called "servo jitters" on a fresh pack. I have seen a C&H ignition get toasted though on a freshly charged 6v pack.

ParticleMan

My Feedback: (24)

People say this, but I have never noticed the difference, mainly because I haven't tried two packs of the same mah to see. If I can fly all day on my 1200mah 6v and fly all day on my 1200mah 4.8v pack then I don't think it's a real concern! Fact is nicad/nimh on 6v, the difference in discharge time is negligible and well worth the benefits of running 6V.

ChuckAuger

My Feedback: (12)

For the same capacity pack, 6V will drain faster.

Think about it..if you get more speed and more torque from the servos, and your pack has the same capacity, it will have to drain quicker.

But, a 1650 Mah NiMh is the same physical size as a 600 Mah Nicad, so if you are thinking "size" vs "capacity", I can see where it could be confusing.

TLH101

My Feedback: (90)

You do not wany to fly below 6v with a 5 cell pack. The point I was wanting to get across, is "IF" you forget it is a 6v pack, and it checks at say, 5.4v you will assume you have enough to fly. You don't! When a cell reaches about 1.1v ( I think) the voltage will fall off rapidly. A 6v pack with 5.5 volts or less has no reserve power left. A 4.8v pack with 4.4v has no reserve.
Now, is everyone confused? If so, maybe someone can explain it better than me.

rfw1953

My Feedback: (2)

I'm really glad Jeff brought this subject up and it can be confusing. The important thing as I now understand is be aware of the voltage difference in a 4.8v pack vs a 6v pack when checking the minimum voltage to stop flying. The only difference I see is that you are adding 1.2v more by adding a 5th AA cell. So, if 4.8 volts on a 4 cell pack is the bottom no fly minimum, then if you applied the same logic, when a 5 cell 6v pack drops to 6v you would stop flying with the same margin for safety as a 4 cell pack.

Jeff provided an important point that I would not have thought about and this could have cost me an airplane. If I used the same tester reading of 4.8v as a no fly point on a 5 cell 6 v pack, it would be the same as running a 4 cell pack down to 3.84v., which would be well below what I and many others use as a minimum. I realize this is a conservative minimum level so lets just use this level as a reference point to understand the differences in this comparison.

So, one last question on this. Jeff sticking with a NiCd 5 cell pack, what is the minimum voltage standard you guys are using for a 5 cell 6v pack? Is it as simple as using the same logic, or because of the extra cells do you guys find you can go safely below 6 volts, say down to 5.8 and still feel there is a margin of safety? Or, would this be exactly the same as flying a 4 pack down to 4.6 volts? Just wondering if by having more cells you can confidently go lower than you would when using a 4 cell pack.

fiveoboy01

My Feedback: (3)

rfw, from what I have learned from those MUCH more experienced than me, concerning no-fly-time for 4 or 5 cell packs:

When it hits 1.2 or 1.1 volts per cell, quit flying. Doesn't matter whether it's a 4 or 5 cell pack.

Robby

My Feedback: (18)

Ok,, now along these lines...

To what voltage DO you get on a fresh charge NiCad ..?

What voltage DO you get on a fresh charge NiMH.. ?

I have been using Nicd forever.. Even 6v..
I recently switched some planes to NiMH...
NONE of my planes have regulators...
None have experienced servo jitters on fully charge battery..

Howevrr,, I did notice on the one plane,with FUT 9202 that when
battery gets to, or below 6v, it does get servo jitters... WHY .. ?

rfw1953

My Feedback: (2)

Robby, I'm learning about this myself, but your question regarding why you get the jitters or noticeable drop in servo response at 6 v. on a 5 pack is exactly what we have been talking about. A 6v read out on a 5 pack is the same at a 4.8 readout on a 4 pack. Or as a previous poster said , you are at the 1.1 to 1.2 v per cell minimum threshold and you should recharge.

As for the maximum read out at a full charge you should be able to get close to 7 volts on a 5 pack. I don't believe it matters whether or not isn't a NiMh or NiCd. Now let's see if I learned this correctly and hear what the others say, but this is what I have learned myself from this exercise.