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        New Mega's 16/20/2 and 16/25/2 for ducted fan

#1 Jones Boy Mar 09, 2004 10:08 AM

New Mega's 16/20/2 and 16/25/2 for ducted fan
 
Mega have just informed me that these motors are suitable for Lipo use.
These motors are due to be on the shelves in a month or so.

16/20/2 35A Max 3100 rpm/V and 16/25/2 35A max 2650rpm/V

Both motors are discribed as 400-480 replacements can this mean 400W-500W from a mega in a mini fan?

Thought you would like to know the Latest

Graham

#2 Haldor Mar 09, 2004 10:25 AM

Re: New Mega's 16/20/2 and 16/25/2 for ducted fan
 
Yes Meteor posted a thread about these 16/25's a little before xmas. Their kv is a little low for current NiHM/NiCd standard packs but if you increase voltage (good for LiPo) they should perform very well. 450W should be within reach but as with everything max power is very duration/cooling dependant.

Looks like a good motor :)

#3 Jones Boy Mar 09, 2004 10:39 AM

Haldor

I think you will find these are 2 Turn motors meteor was refering to the 3 turn?

KV is much higher 3 turn is 1700rpm/V

Graham

#4 meteor Mar 09, 2004 04:40 PM

2-turn not so good...
 
1 Attachment(s)
Hi!


I've got one of the new 16/25/2's, and it turned out to be a bit of a disappointment...

In my Kyosho EDF tests, it turned out to be a little less efficient than even the 16/15/x series!


I don't know if I have a bum motor, or what, but the numbers don't make a lot of sense...

I'm going to reserve final judgment until someone else tests this motor in a similar manner.


I've included the Excel file, but be careful to compare apples to apples. (Be sure to pick a consistent target RPM, and try to find a match across all the motors, as the apparent "efficiency" (RPM/Watt) will increase as the power level drops)


I'm in the midst of trying to get a high-end power supply, so I can test motors in a completely consistent manner. (like this: http://cgi.ebay.com/ws/eBayISAPI.dll...category=32720 , but I'm waiting for a 0-20V, 0-50A version to appear on E-Bay)

Essentially, a power supply like this one will allow you to pick a target RPM for a given prop/fan, and them simply increase the voltage until you meet that RPM with each motor under test.

You then record the amps drawn, and move on to the next motor

(I attempt to simulate this with different battery counts/types, but it's a bit of a crap-shoot the get the RPM you're looking for)




I now have a MiniFan 480, so I can do a lower-load test as well.



Hope this helps.


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