RunRyder RC
 5  Topic Subscribe
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 814 views
HelicopterMain Discussion › Helicopter Current draw
06-09-2017 01:13 PM  6 months agoPost 1
French_Heli

rrNovice

Saint Amour France

My Posts: All  Forum  Topic

I am flying a Trex 700 with the GT 15HZ gas motor. It is flybarless and the Gpro is installed. It flies extremely well and is very stable, a bit too stable with the beginner setup on the Gpro. I had many problems with interference so I installed two batteries one for the ignition and another for the rest. I first installed a switching regulator for the receiver and servos but I still had problems a linear regulator solved this and I grounded the batteries separately to th motor. My question is how much current draw this setup with the standard digital servos should be. After flying for about 20mins I had problemsss but managed to land and found that my receiver battery had 15% left and charging was 1.9Ah. Taking an average from these measures gave me a mean current draw of ~6A.
Is this about Normal?
Thanks for any help.

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 01:43 PM  6 months agoPost 2
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

The latest, hi-torque digital servos can draw some serious current if you're "smacking" your heli around.

Just check your batt. before each flight and have a field charger.

Assuming your not stalling a servo with the linkage? Or some other mechanical issue.

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 03:29 PM  6 months agoPost 3
Flyin for Jesus

rrVeteran

Dana Point, Ca. 92629

My Posts: All  Forum  Topic

I can't remember exactly but my 770 draws much less than that with BK servos.
You can possibly dail down your cyclic gain and see if your power consumption is less. But a gasser is a higher vibrating maching and the FBL may keep those servos always moving if it can't filter out vibes from actual heli movements.
But lowering the gain might make a difference???

PM  EMAIL  Attn:RR  Quote
06-09-2017 03:55 PM  6 months agoPost 4
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

Could be...

If the inflight telemetry devices could sample at a much higher rate, it might become clearer as to what exactly is going on.

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 04:18 PM  6 months agoPost 5
RM3

rrElite Veteran

Killeen, Texas - USA

My Posts: All  Forum  Topic

maybe You have a bad RX pack or its going bad... have you tried swapping it out for a new pack and check the remaining capacity then?

I fly a gasser with a single 3S, 2200mah lipo... it runs both the CDI and RX with a CGY750 and brushless Futuaba servos. I get 4 flights max at 12 minutes each(I usually just go 3 so that the packs come down at storage charge levels)...

one day a pack only gave me two flights... but it charged up as normal, the pack was simply old and going bad.

showing a preference will only get you into trouble, 90% of everything is crap...

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 04:33 PM  6 months agoPost 6
Richardmid1

rrProfessor

Leeds, England

My Posts: All  Forum  Topic

It's simply vibration getting to the gyros making the servos work harder. Best fix is to isolate the FBL unit from the vibes by trying different mounting tape and mounting locations. Thick tap isn't always better remember, some gyros like to be almost hard mounted.

60% of the time, it works every time!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
06-09-2017 04:40 PM  6 months agoPost 7
Dr.Ben

rrMaster

Richmond, VA, USA

My Posts: All  Forum  Topic

A set Futaba BLS servos for example will draw somewhere in the 300's ma/ flight. Others may consume WAY more.....

Ben Minor

Team Synergy Team Futaba Team Kontronik USA
Progressive RC

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 04:48 PM  6 months agoPost 8
ssmith512

rrKey Veteran

Indianapolis, IN USA

My Posts: All  Forum  Topic

A set Futaba BLS servos for example will draw somewhere in the 300's ma/ flight.
I have used Futaba BLS pretty much exclusively for years and can concur with that factoid. Doesnt matter if it wass a 600 nitro, 700 nitro, 700 electric, 600 electric, 800 scale, or 1050mm scale turbine (all based on 6 minute average flight time).

Steve

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 05:03 PM  6 months agoPost 9
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

Which Futaba servos?

I can't seem to find BLS275s in stock anywhere(I think that's the #)...

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 05:15 PM  6 months agoPost 10
ssmith512

rrKey Veteran

Indianapolis, IN USA

My Posts: All  Forum  Topic

Which Futaba servos?
I can't seem to find BLS275s in stock anywhere(I think that's the #)...
I've used them all, starting with the old BLS451 many years ago. My pod and boom now has BLS272 on the cyclic, BLS276 on the rudder. I have BLS371 on the big scale turbine cyclic and BLS177's on the retracts.

Steve

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 05:22 PM  6 months agoPost 11
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

Aren't the BLS275s the cyclic counterpart to the BLS76s?

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 05:47 PM  6 months agoPost 12
ssmith512

rrKey Veteran

Indianapolis, IN USA

My Posts: All  Forum  Topic

Yes. But I am cheap ass and my flying skills dont warrant the premium cost for the 275

Steve

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 05:51 PM  6 months agoPost 13
Dr.Ben

rrMaster

Richmond, VA, USA

My Posts: All  Forum  Topic

The BLS 272SV uses the same case dimension as the 276 but has less speed, torque, and cost than the 275. The perform admirably​ for the vast majority of modelers and are stunningly reliable.
The 275 is their flagship heli servo with all metal case and more speed and torque. You can also look at the 273 which is the same servo with a plastic case top for less cost per servo.

Ben Minor

Team Synergy Team Futaba Team Kontronik USA
Progressive RC

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 05:53 PM  6 months agoPost 14
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

So where does one get the BLS275s?

Not in stock anywhere in the US....or even in Europe that I can see...

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 05:56 PM  6 months agoPost 15
JuanRodriguez

rrProfessor

The Villages, Florida

My Posts: All  Forum  Topic

Tower Hobbies for one...

In stock. Only $250 a pop to your door .....

Been there, done that and old enough to know better.....

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 05:59 PM  6 months agoPost 16
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

Last time I checked....not in stock...the BLS276 is...but not the 275s

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-09-2017 06:00 PM  6 months agoPost 17
JuanRodriguez

rrProfessor

The Villages, Florida

My Posts: All  Forum  Topic

According to the website, in stock limited quantities....

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDXFM

You gonna run out and get a half dozen or so, right ??

Been there, done that and old enough to know better.....

PM  EMAIL  GALLERY  Attn:RR  Quote
06-09-2017 06:04 PM  6 months agoPost 18
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

Wow...they are...

Nah, I got some HSB-9370THs....

Oh well, maybe next time...

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
06-10-2017 05:29 PM  6 months agoPost 19
Richardmid1

rrProfessor

Leeds, England

My Posts: All  Forum  Topic

Most efficient setup is to run HV servos on 6v or a straight li-fe rx pack. Also slower higher torque servos will be more efficient.

60% of the time, it works every time!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
06-10-2017 05:45 PM  6 months agoPost 20
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

"Also slower higher torque servos will be more efficient."

Slower?

Why is that good?

Logo 600SXs, 800XX, TDR IIs

PM  EMAIL  Attn:RR  Quote
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 814 views
HelicopterMain Discussion › Helicopter Current draw
 Print TOPIC  Make Suggestion 

 5  Topic Subscribe

Monday, December 18 - 10:50 am - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online