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Mega 22/20/2 question

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Old 01-21-2007, 02:36 PM
  #1
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Default Mega 22/20/2 question

I have been running my Mega 22/20/2 with a Castle 80 ESC on a 10 cell 3300 pack. I am now in the position to get a lipo. Another motor I have requires a 4s lipo. Can I run the Mega on a 4s pack without burning it up or damaging the motor ?

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Old 01-21-2007, 08:15 PM
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Default RE: Mega 22/20/2 question

Campy,

Yes you can run it on 4S lipoly without problems.

Since you are going to increase the voltage, your amps will jump up big time using the same prop.
So you must reduce the size of your prop to take the amps back down.

I'm running a MEGA motor similar to yours but smaller size, the MEGA 16/25/2 2650KV rated for 35A.
I have been running my motor on 3S-3800 and 3S-5000 at 75-85Amps and have had no issues and motor has been staying cool, my friend has the same setup and loves it. So these motors are under rated big time.
I also run a 4S-3300 at 92A 1330W with Graupner 6X6, CC80A ESC on high advance and no problems.

I don’t know if you have a gear reduction or are running direct drive.
If direct drive you may want to try a 5.5X5.5 prop or keep the amps down by using a 5.5X4.5

If direct drive and you want to be super...super conservative till you get a hold of wattmeter, then try 5X5.
Personally I would go with the 6X6..that is if you need speed.
For max climbing you don't want a prop that has Diameter/pitch ratio of 1:1......You will need a diameter that is numerically more than the pitch (usually no need to go over 1.5:1)

All depends on airframe and type of flying desired.

I hope you have a wattmeter, if not don't worry: if my little motor can hold up well till my Castel Creations Phoenix 80 cuts off due to too many amps.....You should have no problems. Your motor can handle more than your ESC and a lot more than my motor.

I've tested my little motor on 5S and 95A at 1600W in my room, but I think that was too much for sure.

I do have a MEGA 22/30/2 1700KV that is going to be seeing 100+ Amps.

Try to buy a Lipoly that has a high C rating like Thunder Power Extreme series 22C cont/50C burst like a 3300-5000 mAH depending on size/weight. 3300, 3800 are shorter than 3400, 3850. The 5000 is only slightly longer than 3300. TP Web site is full of errors.

Also look at Hyperion LVX series they can discharge very nicely as well, better than most other 20C lipos.

That is my 4 1/2 cents above.

Good luck,
Gryphon
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Old 01-21-2007, 08:34 PM
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Default RE: Mega 22/20/2 question

Campy,

CC Phoenix ESC from 35A to 125A are not rated for 4S as far as the BEC chip goes.
The BEC means battery eliminator circuit.
BEC is a small chip on the ESC that feeds 4.8-5V juice to the receiver and servos.

Your 80A ESC is rated for up to 6 cell lipoly, but at 4 cell lipoly you need to run an external BEC for about $25-$35 depending on the amp rating needed for number of servos used.

At the same time you need to disable your CC80 red wire that goes to receiver so it does not give 5V to receiver anymore, because that is being done by the new Universal BEC "UBEC"

**** Instead of UBEC you can run a separate 4.8V flight pack just like in Fuel/GAS planes/cars/helis.

You can disconnect the red wire in several ways.

1) run a OPTO Isolator for $16
2) cut the red wire and tape it on both ends
3) remove the red wire from the connector and tape it.
4) to avoid messing with the red ESC wire and buying OPTO Isolator, connect a short servo wire extension and do either step 2 or 3 above to the extension wire.

Note: some of the UBEC that are available come with a secondary output that is useful...just read your manual.

Brand names for UBEC: Medusa Research is one such unit.

Make sure to install UBEC as far from the receiver as possible, less of an interference issue if a Spektrum radio at 2.4 GHz is being used.

Feel free to contact Castle Creations to discuss this subject.

Since you are at it, you can get the UBEC at 5V or higher 6V. The 6V units make the servos work faster and be stronger. I run 6V in all of my planes. Electric or Fuel powered.

Hope you find the above useful.

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Old 01-21-2007, 10:11 PM
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Default RE: Mega 22/20/2 question

Hi Gryphon,

Thank you for the info on disconnecting the BEC. I haven't changed it over yet because I have not gotten the lipo yet.

I have a UBEC, but I haven't decided if I will use the UBEC or a separate battery pack.
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Old 01-21-2007, 10:30 PM
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Default RE: Mega 22/20/2 question

Quote:
ORIGINAL: Gryphon

Campy,

Yes you can run it on 4S lipoly without problems.

Since you are going to increase the voltage, your amps will jump up big time using the same prop.
So you must reduce the size of your prop to take the amps back down.

>I was initially running the motor on a Freedom 3D with the following set
>up (the setup was pulling about 48 watts [amps ? ] at full throttle:

>5:1 monster gearbox, 16x8 eprop and bec engaged.

>It is now on a Clancy "Speedy Bee" set up as follows:

>3:1 Monster gearbox, 12x10 eprop. I will have to disconnect the
>BEC and either use a UBEC or a separate battery pack. As far
>as I am able to determine from MotorCalc, this setup SHOULD
>pull about the same as the setup on the Freedom.
>
>I am looking at a 15C 4S 4,100 or a 20C 4S 4,400 pack.
>The 20C pack looks like the way I will go. I found the 4S pack
>at United Hobbies < https://www.unitedhobbies.com/UNITED...idProduct=4133 > for $81.75 plus shipping.
>
>Yeah, I know - a LITTLE ??? over powered (actually the wings
>are optional with this setup ) but that is what I had available
>to put in it. Oh, save your money. The Speedy Bee ARF is the
>biggest piece of sh*t I have EVER SEEN in an ARF. I did more
>modifications/repair work to this plane to make it flyable then you
>would believe. I just should have built one from scratch, it would
>have been easier.


I'm running a MEGA motor similar to yours but smaller size, the MEGA 16/25/2 2650KV rated for 35A.
I have been running my motor on 3S-3800 and 3S-5000 at 75-85Amps and have had no issues and motor has been staying cool, my friend has the same setup and loves it. So these motors are under rated big time.
I also run a 4S-3300 at 92A 1330W with Graupner 6X6, CC80A ESC on high advance and no problems.

I don’t know if you have a gear reduction or are running direct drive.
If direct drive you may want to try a 5.5X5.5 prop or keep the amps down by using a 5.5X4.5

If direct drive and you want to be super...super conservative till you get a hold of wattmeter, then try 5X5.
Personally I would go with the 6X6..that is if you need speed.
For max climbing you don't want a prop that has Diameter/pitch ratio of 1:1......You will need a diameter that is numerically more than the pitch (usually no need to go over 1.5:1)

All depends on airframe and type of flying desired.

I hope you have a wattmeter, if not don't worry: if my little motor can hold up well till my Castel Creations Phoenix 80 cuts off due to too many amps.....You should have no problems. Your motor can handle more than your ESC and a lot more than my motor.

I've tested my little motor on 5S and 95A at 1600W in my room, but I think that was too much for sure.

I do have a MEGA 22/30/2 1700KV that is going to be seeing 100+ Amps.

Try to buy a Lipoly that has a high C rating like Thunder Power Extreme series 22C cont/50C burst like a 3300-5000 mAH depending on size/weight. 3300, 3800 are shorter than 3400, 3850. The 5000 is only slightly longer than 3300. TP Web site is full of errors.

Also look at Hyperion LVX series they can discharge very nicely as well, better than most other 20C lipos.

That is my 4 1/2 cents above.

Good luck,
Gryphon
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Old 01-22-2007, 05:55 PM
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Default RE: Mega 22/20/2 question

Campy,

I just ran MOTOCalc, Given your setup; you may be pushing it too much.

If you really want to run that prop, I think you should look at 4:1 gear reduction. I think 3.5:1 is border line and 3:1 would over heat the motor.

If you want to keep the 3:1 gear ratio, consider going with a smaller prop.

Do you have access to a wattmeter and/or temp gun?


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Old 01-22-2007, 06:14 PM
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Default RE: Mega 22/20/2 question

Campy,

I was looking at my simulation of MOTOCalc again. I think I know where we have some differences.

1) most important: you probably have chosen APC prop which shows P.Const of 1.11 , I only find that value to be close when talking about 5" props or less. In my experience I get closer values when I manually choose 1.6 for 7" props.
I think it is better to error on the side of caution....funny coming from me who am running twice the rated amps on my motor. But that is after lots of testing with many tools on my particular motor.

2) Although a smaller factor: battery. Not all 20C batteries perform the same in reality and in MOTOCalc. I find that Hyperion LVX series give the best performance on MOTOCalc so for 20C or 22C batteries I choose the closest size. For yours I chose 3700mAH. Again because they perform so well and to error on the side of Caution. If a smaller battery shows that you over heat then what about a bigger battery that will drop the voltage less...higher voltage means even more amps and more heat.


The P.Const of 1.6 will show that your motor temp will rise too much with your 12X8 prop and 3:1 gear ratio
I believe your amps are going to be less than MOTOcalc shows and your battery voltage will be higher than it shows, so your power(watts) will not be too far off (fingers crossed)...It is the amps that heat up your motor.

I'm sure if you talk to Ken the U.S. distributor of MEGA motors that he will tell you that the figures on his site are approximate and that you can run even a 5 cell lipoly. With 5S you can use a bigger gear reduction to make the same power as you desire on 4S but to lower the amps. More voltage, less amps= same power output but cooler running motor.

Also the www.megamotorusa.com web site shows 14 cells max for your motor which is about 4 1/2 cells lipoly.
On that site on far left click on airplane, then on middle section click on motor specifications, and then pick your motor. Keep in mind that they show very conservative examples.

Hope that helps
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Old 02-01-2007, 04:39 AM
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Default RE: Mega 22/20/2 question

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Old 05-21-2017, 12:59 PM
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Default

Bit of a BUMP, but someone may be able to help me, as I found this post of use.

Hi, test flew a model today here in the UK.

Used to be a IC engine model. (Chilli Breeze)

Now it is has:

Mega Motor 22/30/2 Brushless Motor
Saker 80amp ESC
4s 3200mAh Lipo
APC Electric 10 x 6 Prop


Anyhow, i forgot to test it with a 'watt-meter'

It flew fine and took off of the ground very fast. Plenty of power.

Problem was, about 2-3 minutes into the flight, I lost motor power.

Landed and checked model over.

ESC was warm
Motor was warm
Lipo's were fine.

Motor was now stuttering, pulsing, certainly now spooling up at all.

Anyhow when I came home. I I stripped motor & esc from the model, removed prop and re-tested.

Motor seemed now to spool up fine and go to full speed. (this is without prop on)

I have not programmed the ESC, will check that perhaps?

Any idea what my issue may have been?


Many thanks
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