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Oct 29, 2019, 02:42 PM
indywestrc & viehercfliers
Suds's Avatar
Quote:
Originally Posted by RoeeZvi
Hey,

The stock structure if not large enough for the equipment.
This is the BOOMA RC :
What we're trying to communicate - the Booma equipment is not necessary for a simple 60cc electric build out. It is just added weight not necessary for an airplane of this size. The build out could be much simpler and lighter with one receiver and two receiver packs or BEC plus a backup device.
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Oct 29, 2019, 02:50 PM
DFC~ We Do Flyin' Right
Vapor Trails's Avatar
^ what Suds said.
Oct 30, 2019, 11:11 AM
Registered User
I am using 5 servos Savox 2270 . Stall Current (at locked) of each one of them is: 6000mA @6.0V, 7400mA @7.4V. I use 7.4v.
I am not sure the receiver can contend with that current-thats why I want to use Booma RC
Oct 30, 2019, 01:07 PM
"I will return" Federico
rclad's Avatar
Another option to consider is the Frsky RB-10. It will isolate any servo that exceeds 5A for more than a minute. You can connect two receiver batteries and two receivers. Only 10g. I have been using that in my 95" with a Booma RC Hidden Switch. Over 600 flights on it and no issues.

For more channels and additional features there is also the RB-20.

You can see my installation and a schematic here.
Oct 30, 2019, 02:58 PM
I fly, therefore, I crash!!!
SteveT.'s Avatar
An even less expensive method is the Servocity power board. And Servocity does ship internationally.

SteveT.
Latest blog entry: My shop....
Oct 30, 2019, 09:19 PM
indywestrc & viehercfliers
Suds's Avatar
Quote:
Originally Posted by RoeeZvi
I am using 5 servos Savox 2270 . Stall Current (at locked) of each one of them is: 6000mA @6.0V, 7400mA @7.4V. I use 7.4v.
I am not sure the receiver can contend with that current-thats why I want to use Booma RC
The current line of receives from most companies have a strong servo power bus. I'd have no problem running 1 receiver in the 95 Extra (and I did in my 100cc) as long as powered by two servo input ports.
Oct 30, 2019, 11:27 PM
I am not a robot
Sideslip's Avatar
I don't fly the size planes that you guys do. But my 78" Extra is set up just that way. I have no concerns about power failure to the Rx and the servos.

Unfortunately the brain trust at Amainhobbies has stopped making the best power lead I've found other than custom built. I'm lucky enough to have two of these sitting on the shelf, plus the one in my Extra.
Oct 31, 2019, 12:05 AM
I fly, therefore, I crash!!!
SteveT.'s Avatar
If you need some, I can make you up some Bert.

SteveT.
Latest blog entry: My shop....
Oct 31, 2019, 05:04 PM
Registered User
dhooks6's Avatar
I think I offered to before as well,. It's just 2 servo leads to a connection of your choice.
Oct 31, 2019, 05:39 PM
I am not a robot
Sideslip's Avatar
Thanks guys, but I still have two of them left sitting on the shelf. That will get me through another year at least.
Nov 14, 2019, 10:17 PM
Onward and Upward.
CatManDu's Avatar
What a thread, just finished it. I'm trying to convert a Hangar 9 33% Extra 330L to electric. This thread really helped.
Nov 14, 2019, 10:30 PM
Now I'm a "Low Flyer"
high flyer Rich's Avatar
Quote:
Originally Posted by CatManDu
What a thread, just finished it. I'm trying to convert a Hangar 9 33% Extra 330L to electric. This thread really helped.
What electric setup are thinking of installing?
Nov 15, 2019, 12:15 AM
Onward and Upward.
CatManDu's Avatar
The Xpwr 60 with 2- 6s 6-7000mah LiPos. Probably 2 - 1300 rec. packs with a Hobby wing 200 esc. I have to get a new Futaba transmitter for all the programming for now.
Nov 15, 2019, 09:24 AM
DFC~ We Do Flyin' Right
Vapor Trails's Avatar
What transmitter are you currently using?
What is your intended setup for your Extra?
How many servos, channels, etc?
Nov 15, 2019, 12:50 PM
"I will return" Federico
rclad's Avatar
Quote:
Originally Posted by CatManDu
The Xpwr 60 with 2- 6s 6-7000mah LiPos. Probably 2 - 1300 rec. packs with a Hobby wing 200 esc. I have to get a new Futaba transmitter for all the programming for now.
A couple numbers to keep in mind for an IMAC setup are Wing Cube Loading (WCL) and Estimated Flight Time (EFT). My 95" was very competitive in the Intermediate class with a WCL of 9.5 (max. AUW of 20.6 lbs) and EFT of about 9 minutes using 8 Ah packs. I think a WCL of 10 or lower is OK for IMAC; the 3D guys prefer something in the low 8 range. The lower the WCL, the floatier the plane will feel, which gives you more time to stay ahead of the plane when doing aerobatics.

The formula for WCL is:

WCL = W/(S^1.5)

where W = weight in ounces; and S = wing area in square feet (area in sq. in./144)

If you aim for a max WCL of 10, then your max AUW for the 330L (wing area of 1750 sq in) must be

W = WCL * (S^1.5) = 10*((1750/144)^1.5) = 423.7 oz (26.5 lbs)

The formula for EFT (in minutes) is:

EFT = (C*0.80*60)/((Power Usage)*A)

where C=battery capacity in Amp Hours; Power Usage is average for the flight (40%, or 0.40, is typical for my IMAC flights); and A = max Amps (from eCalc).

So, if your expected max amps is 120A, then

EFT = (7*0.80*60)/(0.40*120) = 7 min.

That should be sufficient for two Basic sequences, but it won't leave much time for loitering before or after the sequence or performing extra maneuvers during practice. EFT is affected by wind conditions, so you will have less time in the air on windy days, and even less if you are fighting a cross wind. To achieve a 40% average power usage you must throttle back to idle (or off) at the top of vertical maneuvers and maintain the lowest possible throttle setting between figures.


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