Originally Posted by guapoman2000

Ultimate BEC provides 3 Amps of output versus your susgestion of 1.25 Amps, also, the Ultimate BEC by Kool Flight Systems is a Shielded PCB and inductor is used to ensure that radio performance is not degraged.

ParkBEC also uses a shielded inductor and a custom ground plane PCB. This isn't really a "feature." Its just good design practice.

UBEC and ParkBEC really shouldn't be considered major competitors. If what you're running is a plane using six or seven high torque servos - say, a hotliner, then UBEC is clearly the way to go. If you're running a 60 sized heli, then go with the UBEC. If you're running four HS-81s in a CAP, why carry the extra twelve grams and pay the extra money? ParkBEC and UBEC are both good and reliable switching supplies. One is bigger, heavier, higher capacity and more expensive than the other. Similarly, HS-55s and HS-422s are both good and reliable servos. It used to be that servos only came in one size - "standard" and thats what you used in all products. It used to be that switching BECs only came in one size. Now, just like you can purchase the right size servo for nearly any job, you can buy the right size BEC.

Originally Posted by Comatose

If you're running four HS-81s in a CAP, why carry the extra twelve grams and pay the extra money? ParkBEC and UBEC are both good and reliable switching supplies. One is bigger, heavier, higher capacity and more expensive than the other.

You be surprised how much HS-81 draw and especially 4 and which is exactly what Mike has experienced while using the BEC onboard the PHX-45 from his accounts.

Actually, I wouldn't be that suprised. They're hungry little servos, to be sure. Hungrier than most "standard" servos. That doesn't mean they can't be measured in-flight.
http://www.dimensionengineering.com/ServoSense.htm

A ParkBEC will handle four HS-81s. It about the far edge of its capacity, and is the edge of its rated specs, but it'll fly them all day in 110 degree heat without shutting down. Five, I'd go UBEC for sure. UBEC is a fine product and if your weight and cost budget both have the extra room, the extra capacity can't hurt.

Four HS-81s on a linear BEC, even a "3A" linear BEC, will put the hurt on the BEC very quickly.

The CAP is about the largest size model where I'd use a single ParkBEC and about the smallest model where I'd use a UBEC. Usually its a no-brainer one way or the other. There's a certain 12g BEC that I'd just flat out avoid (which is where a lot of the UBEC or nothing opinions come from.)

Oh, I understand.....thanks for your thoughts on alternate BEC's

All this discussion on BEC reminds me of that commerical ...

"If it ain't BEC Powder" something about anti acid or pain relief.

These are the readings taken from my .40e... with 4 HS-81's 3S2P 2080 Apogee 12.1v in.

1.5A Peak (Highest in-flight reading)

.20A Average Draw (Average for entire flight)

.5A Max Draw for Sustained for 15 seconds. (Highest Average Current draw over a 15S period)

On the ground without running the motor I motivated all four servos to work full stop - to full stop for 1 min then checked the BEC temp with an IR gun - Did this about 3 times - peak temp was no more then 155deg. F

Need to do an independent servo test as well.. as I got one with the jitters. Anyhow... seems to me a servo load monitor is just as mission critical as a watt meter....

Mike would be nice to compare notes once you have had a chance to verify your setup.

Originally Posted by guapoman2000

You be surprised how much HS-81 draw and especially 4 and which is exactly what Mike has experienced while using the BEC onboard the PHX-45 from his accounts.

Yes When I get the Tester I will post the results. I will even make an inflight to see what it is doing.

Of coarse that 155 deg F in Colorado 70 deg temps could get some higher here in the Swampy, Steamy, hot air (90 +) of N.Central FL.

Mike

Originally Posted by mrm1

Of coarse that 155 deg F in Colorado 70 deg temps could get some higher here in the Swampy, Steamy, hot air (90 +) of N.Central FL.

Mike

Mike,

You can count on this heat to really "Tax" any electronic device and especially the super high humid conditions that we just don't see and take for granted.

Carlos.

Got the package from SA today containing among other things, the Castle Link Update cable and the Servo tester.

Not wanting to bad mouth any vendor, let me just say, don't believe everything you hear - even when you ask and are told it will be done a certain way. The seller of my CC Phx 45 ESC assured me he would update the software before shipping. I purchased the ESC new in late May/early June of 05. The Castle link just told me my software version was v1.041 which takes us back to 8/2/04. Take a look at the updates since then. Half of them sound like my heating problem already being addressed?

That said, I have updated the ESC to 1.161 Beta and will test the servos when I get home tonight. Hope to remaiden on Friday AM. More info to follow as servos get tested.

Mike

PS, Thanks Bill for that Quick SA service.

Tell you what it's tough living in Colorado

Originally Posted by mrm1

Yes When I get the Tester I will post the results. I will even make an inflight to see what it is doing.

Of coarse that 155 deg F in Colorado 70 deg temps could get some higher here in the Swampy, Steamy, hot air (90 +) of N.Central FL.

Mike

Originally Posted by arenablimp

Tell you what it's tough living in Colorado

All I can say is I have NEVER shoveled snow - Shoot, I've hardly ever seen it unless I wanted too - ie. ski trips.

And it's year around surfing here

http://2ndlight.com/

http://www.surf-station.com/OldSchool.asp

Mike

Originally Posted by mrm1

All I can say is I have NEVER shoveled snow - Shoot, I've hardly ever seen it unless I wanted too - ie. ski trips.

And it's year around surfing here

I surf the net, does that count?

Doug

Originally Posted by unbalanced prop

I surf the net, does that count?

Doug

LOL

Originally Posted by unbalanced prop

I surf the net, does that count?

Doug

There's no sharks on the net...or are there? Maybe Gators lurking in Salt water?

Let me guess Carlos, That is out by 32a & b ?? I think I know that "guy", he nearly nabbed one of my red fish in 1980

OK, now we're off subject .... back to the "heat"

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