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Radio - Servo - Gyro - Gov - Batt > FUTABA BLS-451 SERVO'S- GOOD OR BAD
 
 
legoman67
Key Veteran
Location: Nanoose Bay B.C, Canada

i got rid of mine, didnt want to risk it.. not worth the fear....LOL

Matt M.
http://www.filepile.ca
03-11-2008 04:51 AM
HOMEPAGE  
 
 
turboomni
Elite Veteran
Location: 63 Rambler Down By The Dumpster

Quote 
i got rid of mine, didnt want to risk it.. not worth the fear....LOL


Chicken!!!!!!!

Setup is everything, All my heli's can fly better than I can pilot them
03-11-2008 05:46 AM
 
 
legoman67
Key Veteran
Location: Nanoose Bay B.C, Canada

Quote 
Chicken!!!!!!!

hmm, well when my heli is still in tacked in a month we will see who is calling who names

Matt M.
http://www.filepile.ca
03-11-2008 05:52 AM
HOMEPAGE  
 
 
moyesboy
Heliman
Location: uk

Well I have a 600n with BL451 on ccpm and 720/251 on the tail.
ITs done 10 tanks now only.
Its using the newer design align reg, but I run the AR7000 receiver direct of the 2 cell lipo and the servo power only comes from the regulator at 5.8v, with step down for the gyro/tail. Basically the servo wires split with +/- going to the reg, and the signal wire into the receiver. The power rail I made has a 4700 cap on it to help with start stop current peaks (proably should be bigger).

I use the same setup on my raptor.

the idea is that no matter what the servos pull from the reg the rx still doesn't reboot. How much use that is is open to question.

I had no problems with the 451's and they centre well and have behaved totally predictably - but not many flights yet.

I am considering a bigger reg. but in fact my 600n is a lot easier on the batteries than my raptor which has the same regulator and runs digitals including a DS8411 on collective. The 1900 align lipo was only good for 3 flights on the rappy, but it does 4-5 on the 600n.

Maybe I'm pushing my luck with a 8411 (never recalled or modded or any problewm admitted to in the UK) and BLS451's in my helis...

I wonder how many of the problematic servos are on 7 volts, or two cell A123 direct, JR don't yet admit that more than 6v is possible with their brushless servos.
03-11-2008 01:41 PM
 
 
turboomni
Elite Veteran
Location: 63 Rambler Down By The Dumpster

Legoman

Just rattling your cage man!!
Have you had problems with these servos on the bench,were you one of them or no problems?
I think there are many many more fliers without problems than with problems when running these servos.

Setup is everything, All my heli's can fly better than I can pilot them
03-11-2008 10:17 PM
 
 
Dr.Ben
Elite Veteran
Location: Richmond, VA, USA

Quote 
I think there are many many more fliers without problems than with problems when running these servos.

This is a true statement.

Ben Minor
03-11-2008 11:40 PM
 
 
Rockohaulic
Elite Veteran
Location: Valencia, CA, USA, 3rd Rock from the Sun

Who makes the ReactorX, and who has it in stock?

Don't Just Survive Your Life - Live It!
Team RJX of USA
03-12-2008 12:21 AM
 
 
Funky Trex
Veteran
Location: Westerville, OH - USA

Scott Gray makes them

http://www.scottgrayrc.com/reactor.php
03-12-2008 12:27 AM
 
 
Shiro Muji
Senior Heliman
Location: Japan

I've been using the BLS351 in my gasser with no issue but just broke the ear of the uppercase and I can't find any answer from futaba what compatible casing is available. They don't even answer my email.

Maxum with Hanson 3D Max, Maxum Nitro, Maxum 30.5cc modified engine, RH Generator, Sceadu .50Hyper
03-12-2008 12:37 AM
 
 
mmc205
Heliman
Location: Pottstown,PA - USA

No specs for battery or voltage? can a voltage range at least me given? If not, i assume the warranty will still cover the servo if i put 100 VDC to it? how about a voltage range futaba?

I FIND THE DENSITY OF THE AIR CHANGES SIGNIFICANTLY BELOW 0 ALTITUDE.
03-12-2008 03:09 PM
 
 
bbaxter
Heliman
Location: Central Illinois

Quote 

mmc205
No specs for battery or voltage? can a voltage range at least me given? If not, i assume the warranty will still cover the servo if i put 100 VDC to it? how about a voltage range futaba?

The power rating is shown on the pages that detail the servos. It shows 4.8V or 6V specs, which means the equivalent of 4-cell or 5-cell NiCd or NiMH battery packs.

The 100VDC would, of course violate any warranty because it's outside of the normal realm of R/C hobby practice.

The servos pages:

http://www.futaba-rc.com/servos/index.html
03-12-2008 08:23 PM
 
 
rexxigpilot
Senior Heliman
Location: florida

deafheliflying,

I'm with you on this. I also use the ReactorX. It is used with (3) BLS451's and BLS251 tail on a T-rex600N. No problems at all. IMO, the smoothest, best centering servos I own for heli use.

I have been seeing more and more problems/crashes at my local field, and hearing about many problems on this forum due to underpowered flight systems IMO. People simply cannot expect to use the high power servos we use today with antiquated power systems. 1500MAh Nicd/Nimh as well as 3A and 6A BEC's just don't cut it anymore.

Rockohaulic,

I got mine from AMH for $135. Worth every penny.
03-13-2008 04:41 AM
 
 
NEM3
Veteran
Location: New Lenox, Il

Quote 
deafheliflying,

I'm with you on this. I also use the ReactorX. It is used with (3) BLS451's and BLS251 tail on a T-rex600N. No problems at all. IMO, the smoothest, best centering servos I own for heli use.

I have been seeing more and more problems/crashes at my local field, and hearing about many problems on this forum due to underpowered flight systems IMO. People simply cannot expect to use the high power servos we use today with antiquated power systems. 1500MAh Nicd/Nimh as well as 3A and 6A BEC's just don't cut it anymore.

I think the numbers I posted on page 2 of this thread prove that without a doubt.

I am anxiously waiting for the Spartan's to come back into stock so I can get idle and fully stalled numbers on a full setup.
03-13-2008 06:59 PM
HOMEPAGE  
 
 
Rockohaulic
Elite Veteran
Location: Valencia, CA, USA, 3rd Rock from the Sun

rexxigpilot

How about running the Li-Po directly to the RX, running the cyclic servos at 8.4 volts, and using the Spektrum VR5203 for gyro and throttle.

Is this system adequate to supply power to today's hungry cyclic servos???

Don't Just Survive Your Life - Live It!
Team RJX of USA
03-13-2008 07:47 PM
 
 
NEM3
Veteran
Location: New Lenox, Il

Higher voltage also equals a higher amperage draw.

The problem is not so much the servos sucking down more juice (Although most do to some extent). Its more about the evolution of power systems. Instead of you supplying your receiver from a 4 cell nicad pack. We are using 2S lipo's or li ions. And then running a regulator system to keep the voltage low enough. The problem is that with this scenario, your voltage is always at 5.6V, 5.7V 5.8V or whatever you regulator is set to. Sure your 4 cell nicad pack would charger that high. But as soon as you placed an 8 amp load on it, you would very quickly find yourself down around 5.1V (If using a 2400 Sub C pack) or 4.8V (If using AA sized packs). And this is all on the first flight. As you can imagine things progessively got lower from there. The nice thing about the lower voltage was the lower amp draw that accompanied it. Instead of sucking down 8A of a freshly charged pack, you might be down to 7 amps or lower.

Fast forward to today. Most folks not crazy enough to put Lipo's in the gas choppers run the Li Ion setups. And most of the folks that run them are using a 4800mah pack. This Li Ion freshly charged puts out 8.4V. My 1 year old well used and abused Fromeco 4800 would dip down to 7V under a 9A load. But guess what, on the receiver side of the regulator, the voltage is always (ideally) the same 5.6V. And it will remain that same (as does the amp draw) throughout the charge of the receiver pack. Unfortunately it the exact opposite on the battery side. As the pack voltage drops the amperage must raise in order to provide the same wattage to the regulator.

I can't really comment on the 2S lipo setups, as I am not crazy enough to try them. Nor do I have any numbers on what running a lipo directly to the receiver will do. But its a fact that you will be pulling more watts per flight than a regulated or 4.8V system.
03-13-2008 08:39 PM
HOMEPAGE  
 
 
rexxigpilot
Senior Heliman
Location: florida

Rockohaulic,

IF your receiver's power bus can handle 9-10 or so amps, you should be OK. Many can't! If the receiver bus has too much resistance, it will ultimately burn out or not provide the necessary voltage X current (wattage) the servos need. That is the reason for the ReactorX. The swash servos are driven directly from the ReactorX's powwer bus, not the receiver's. The control signal from the receiver is mixed with the power output of the ReactorX to drive the swash servos. The receiver's power bus can then provide the relaxed current demand of the gyro/tail servo, governor and throttle servo with ease.
03-14-2008 07:13 PM
 
 
JKos
Elite Veteran
Location: Town of California in the state of Maryland

> IF your receiver's power bus can handle 9-10 or so amps

The limiting factor are the standard servo type connectors. The copper on the rx can easily handle 9-10 amps.

- John

Logo 14 -- Logo 10
03-14-2008 09:20 PM
 
 
rexxigpilot
Senior Heliman
Location: florida

Quote 
The copper on the rx can easily handle 9-10 amps.

JKos,

Are you certain the typical receiver bus is capable of 9-10 amps? Have you tested this or have specification literature from the various manufacturers which confirms your statement? If so, could you please post it for all our benefit.

I agree the servo connectors/leads are also a source of high resistance, especially if only one electrical supply connection is made with the receiver. As I'm sure you know, typical connectors are rated at about 3amps continuous and 5 peak.

The last time I had the opportunity (read crashed hard enough to break open receiver case) to look inside a modern receiver and see the power bus, it didn't have much cross sectional area - certainly less than that of the combined pins from 2 servo connectors. It also wasn't made of highly conductive material like silver or even gold, just plain old copper.

Bottom line, the BlS-451's exhibit no glitching or bad centering in my installation, but I do have a robust power system.
03-14-2008 10:49 PM
 
 
Ace Dude
Elite Veteran
Location: USA

Does anyone have any actual, in-flight, data showing these 9A-10A current peaks with respect to time?



03-14-2008 11:32 PM
 
 
JKos
Elite Veteran
Location: Town of California in the state of Maryland

rexxigpilot,
This has been discussed on RR and other forums many times over. Data was provided in at least some of the discussions. I believe Paul Beard even disclosed the copper cross-sectional area on the Spektrum receivers (or at least one model).

> It also wasn't made of highly conductive material like silver or
> even gold, just plain old copper.

BTW, copper is more conductive then gold.

- John

Logo 14 -- Logo 10
03-15-2008 01:04 AM
 
 
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Radio - Servo - Gyro - Gov - Batt > FUTABA BLS-451 SERVO'S- GOOD OR BAD
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