JAS

My Feedback: (2)

I didn't think the other crappola thread would be read by many of the electric guys... so here's the e-crappola thread

Here's what I am wondering (pure dazed thought)

Why is it that the motor and controller receive the most 'heat' yet there are some controllers available to us that have no or a very small (too small) heat-sink? I couldn't imagine running a sinkless controller working down here (much less hoping it would make it through the heat in Muncie at the Nats). My Jeti 90, with the massive heat-sink, gets up to 140F and pulling 82A on average. What am I missing?

can773

My Feedback: (1)

Nothing man!

JAS

My Feedback: (2)

[sm=confused_smile.gif] ok... thought I missed the boat again lol

2Sunny

Whoa there pardner' [X(]


What motor/prop combo is it that's pulling 82 amps average?!?


I thought my wimpy 50 to 60 amp averages were high, but obviously you are dealing with some serious power in your sequences!



and as to your ever so pertinent "crappola" post, I must admit that as the new guy I am forever "re-inventing the wheel" as I learn all the tiny aspects you guys have already figured out years ago. Yesterday I tried a Jeti Spin 75 on my E-Motion and 4 minutes into the practice I felt "something" at the top of a stall turn, but chose to press on. Then about a minute later it happened again and this time it lasted long enough for me to figure out, it was a soft cut. When I landed and checked the Spin box measurements I found the temperature cutoff was set at 100 degrees C and the controller had registered a peak temp of 103 degrees C. (For the non-metric types that's 217 degrees Fahrenheit [X(] ) I guess I should count my lucky stars that in this case "re-inventing" the wheel didn't cost me a plane!



Joe

JAS

My Feedback: (2)

It's my Pletty/Jeti 90 Comp/21x14 APC. Been that way since day one, nothing out of the norm. But when it gets hot in the summer down here... it's 140 every flight. In the winter/cooler months it's only 125. If I ever took off my heat-sink my controller would smoke for sure.

Maybe I'm getting the higher A's cause I'm using a larger controller? It's both my Pletty's and also my Fury's.

J Lachowski

My Feedback: (46)

JAS,

When I ran the Hacker Master Spin 99 controller, similar to the Jeti, on the Hacker 13XL and 20.5X14 it ran on the warm side. I suspect it is just older technology/design. My YGE on the Pletty and same prop and similar amps ( 80A max) does not run as warm as the Spin controller.

I think you need Joe (2Sunny) to lend you a few controllers to experiment with<G>.

f3a05

I run a similar set up (APC 21X14, Pletty, Jeti Spin 99), and,although I'.ve never measured temps, the esc is never even warm to the touch on landing.
Admittedly, it's very rare to have a truly hot day here (UK),but we do sometimes have it into the 80s F.
The motor, on the other hand, is frequently too hot to touch at first,on landing.
Could it be something to do with how good/bad the cooling airflows are, on individual models?
Certainly my motor cooling arrangements don't look great.
My esc ,on the other hand,is on stalks right in a good airflow from the front hole in the chin cowl,whereas I've seen a lot of installations with it velcroed/stuck to a fus side,which I'd guess is not as draughty?

J Lachowski

My Feedback: (46)

That might be true about the cooling. My YGE controllers are on the floor right in the airflow through the cowel on the Integrals I am flying now. The Spins I flew in another Integral(a JAS Integral) and Beryll in the past had the Controller mounted on the side of th fuse. If memory serves me, my Spins never got past 115 - 120F on a hot day.

apereira

Hello Jason,

A bigger controller should run cooler, the Amps your motor draw depends on the load, no matter the controller the motor will be pulling the Amps it needs, motors might degrade over time if they ever overheat, if there's no overheat it should not happen; i.e. if a motor overheats, the windings insulation might soften, if to windings short with each other, it will work as a single winding, so you have one less turn but also that one will consume double the Amps, that's how motors degrade and they start pulling more Amps than normal to make the same power, but if it does happens on different motors is a different story.But brake, timing and other programmable functions could affect it too.

Regards

J Lachowski

My Feedback: (46)

I took some readings on my YGE controller today. I flew just 3 flights within a one hour period. Temps outside were 90F and winds were 10-15 mph. Prop is APC 20.5 X 14 on Pletty 30-10 motor. Highest reading on the controller was 118F. Also experimented with switching between a Tru-turn spinner and a CA Models CF spinner with cutouts. Temps on the motor appeared to be about 15 F cooler using the CA Models spinner.

Patterndude1

My Hacker 99 spin controller runs steady at 80 degrees

JAS

My Feedback: (2)

well wouldn't be the first time I did something wrong with electrics lol.

mups53

My Feedback: (41)

15 degrees! Wow Joe that's huge.
I had to do a lot of extra ductwork to get my YGE 80 to stay cool but it's been flawless with the AXI F3A since I made the mods. The heatsink on the YGE 80 is probably too small for praticul purposes but it sure is light. The YGE 90's will have a bigger sink and thus weigh more. Mike

mups53

My Feedback: (41)

Crap #2
I changed everything over to the Hobby King 4MM bullets. I got these with my Zippy's and cut them off. I saw that Chad was using them last year.
Prior to changing to them I was running HK 6MM bullets.
3 times last year I connected the positive and negative directly from the 10S 5000's together while holding them. 2 out of the 3 times it really hurt. The last time it burned the bejeebers out of the tips of 2 fingers and my thumb the monday before the nats. It was simply a system that had opps written all over it. I was dumb but the danger existed and I got distracted each time.
So Chad had a good idea and I love these connectors.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9283&Product_Name=HXT_4mm_Gold_Connector_w/_Protector_(10pcs/set)
Thanks, Mike

wingster

My Feedback: (26)

I maidened a Prestige with the Pletti and Jeti Advance 77 Opto on Sunday. I didn't intend to use the Advance 77 but my YGE controller had not come in yet. It was mounted 7-8 inches behind the cowl opening. I was getting a feel for the new setup and was not really pushing it. The ESC came down at about 135 F( 90 ambient) and cut out at times presumably do to over heating. I'm going to do some ducting and/or add a heat sink.

I have two spin 99 setups that reach 130F or so during the summer. They're mounted on the fuselage sides a fair way back.

Jason Arnold

G'day Mike,

I use Castle 5.5mm bullets and have colour coded heatshrink on them. I also made a small socket out of delrin to put over the male bullets (-Ve) which prevents any shorting.

The plugs connecting the two 5S packs have yellow heatshrink on them. Not fool proof, but you'd have to try pretty hard to screw it up...[&:]

I have seen the results of shorting a 10S pack and it's not nice. Happened to a junior at a previous club I was president of. It scared the hell out of all of us. Have also seen experienced F3A pilots do it too. Black, burnt fingers aren't good!

Cheers
Jason.

2Sunny

Nothing Earth shattering . . . just interesting to note the differences between a new kid like me and an 'ole pro like JAS. I think its the difference between flying big and fast versus flying tight and small, but here's a graph from my early attempts at the Intermediate Sequence with Joey Haye's Integral using a Pleti 30-10, Jeti 90, and an APCe 21x14. Max Amps 70 and an average of 28 [X(]



[img]{akamaiimageforum}/thumbnails/207324/Li21184.jpg[/img]








P.S. No burned fingers with an APP set up for a polarized connection Have I mentioned how much I love my APPs!

J Lachowski

My Feedback: (46)

Mike, that was a sample of one each. The temps were taken after I landed, disconnected battery and then took off spinners to get the reading off of the motor. I don't consider the reading to be accurate, but it definitely appeared to be a lower temp with the CA spinner. Take it for what its worth. At least there is a weight savings on the spinner side.

The YGE 80 controller has definitely run at reasonably safe temps so far for 200 flights to date in one of my Integral.

2Sunny

Posted this in my Jeti vs Castle thread in slightly more detail, but in a nut shell I flew one flight with the Jeti in the position shown in the first picture and got an overtemp soft cutout and a reading from my infrared thermometer of 167 degrees F after landing, but after I took off the shrink wrap and moved the esc to the location shown in the second picture I got a reading of 85 or 86 degrees F for the next 8 flights all when the air temperature was in the mid 70's. I'd say an 80 degree difference shows how critical placement can be [X(]


Joe


P.S. I used a [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=DYN2529]Dynamite Thermometer[/link] to take the readings after landing.

woodie

I have been running Jeti (Hacker) controllers since I converted to electric. My first controller was a Jeti 99 with the large heatsink. After looking at the amps I was pulling and the specs for the controllers, I decided to switch to the Jeti 77 and have been running them for about 3 years now. No issues. Having said that, I will say I do add a heat sink to them as a precaution and it seems to work quite well. I use heat sinks from Radio Shack and they are basically stamped/bent aluminum sinks, very light weight and the perfect size for the Jeti 77 controllers.

See picture below for details. Basically, what I do is cut away the heat shrink from over stock aluminum plate under the label on the controller. I use the outline of the base of the heat sink as the pattern. I use a heat sink compound (also from Radio Shack) applied to the base of the heat sink and set it on the aluminum plate. I use kevlar thread to hold the heat sink in place on the aluminum plate. I have also seen people use JB Weld to attach the heat sink to the aluminum plate. Both seem to work equally well.

The controller sits directly in the path of incoming air from the chin cowl which provides maximum cooling. I have flown the Jeti/Hacker in this picture in 110+ degree temps at Oakdale last year with no problems.

Woodie

Wow, from the looks of the dust on the heat sink, I guess it is time to vacuum out the inside of the plane... ;-)

tclaridge

I was flying a Wind 110e with a Hacker A50-16L on 8S on a hot summer day two weeks ago and had a thermal out with the Jeti Pro 77. I removed the shrink wrap and added a heat sink. I will see if this reduced the temp on a ground round before I fly it again. Thanks for the info Joe.