Problems!! 14MZ 2.4 R6014FS

[Jurgen Heilig]

	Quote: Originally Posted by lazun
	The thing, it is failing within spec range!!!! If you want to talk about who is responsible leave it to the courts to decide.

Well, I have not seen a temperature range for a commerically available RC system to exceed +60°C (= 140°F) and you reported the failures occurred at 164°F.

Jürgen

[grayuk]

	Quote: Originally Posted by 1bwana1
	I don't recall ever seing a report of a Spektrum system failing due to heat because it was mounted under the canopy. Can you point me to one?

There is not a report of a Spektrum ‘knowingly’ failing under a canopy.
But tests of failure temps for XPS, Spektrum and FASST are listed in this thread.
Post # 219

607 failed at 172F, and came back to life at 130F.AR7000 failed at 205F.

So there is around 30F difference on this test.


My point being that it could still fail!
We don’t know what temps are getting to under the canopies. Why take the risk?
Take the rx out of harms way.
If you are worried about the carbon in the Fuselage then just put the 2 aerial ends in the cockpit. Get the rx down under the floor, clear of the beating sun.

Paul

[Flyfalcons]

This is the setup I plan on running in my Comp-ARF

[lazun]

	Quote: Originally Posted by Jurgen Heilig
	Well, I have not seen a temperature range for a commerically available RC system to exceed +60°C (= 140°F) and you reported the failures occurred at 164°F. Jürgen

You didn't read correctly then.

1:47 Rx 115*F (under shield) lifted shield slightly, not letting sunlight hit receivers and read temperature of right receiver only

1:49 No temperatures read put canopy on aircraft

1:53 Rx 135*F receiver failed

Moved plane into shade, took off canopy, read temperature of receiver at 135 degrees F. Let it cool on its own in shade and receiver began working again at 108 degrees F.

[reyn3545]

I couldn't make it to the field to day, but I did a little testing (verification, really) in the back yard. The ambient temp was 85 degrees, and my receiver is sitting on a Smart-Fly power adapter, directly under the clear canopy of my composite 100cc plane.

I let the plane sit in the yard for about 3 hours, direct sunlight. When I checked it, the receiver was 163 degrees. No motor running, no other protection from the direct sunlight, other than the canopy (which could magnify the problem.

When I turned the transmitter and receiver on, there was no signal. I let the receiver cool until it would properly initialize on a power cycle.. it finally did that at about 130 degrees. I think this is consistent with other findings.

I have cans on this plane, with no protective shrouding around them, they are just open to the fuse body. I do have cooling vents cut in the fuse under the cans. I'm going to do some testing this weekend and see how the temps look with the motor running (on the ground).

One quick question for anybody who may have a "floor" in thier cockpit at the bottom of the canopy... have you been able to re-create the problem?

My biplane has all of the gear installed from an opening in the bottom side of the fuse. Its a wood ARF, so I didn't want to let the covering sit for hours in the direct sun, but I did leave it out there for about an hour. When I tested it, the temp of the receiver was exactly the same as the ambient temp.

So, if it holds true, I might build a full platform at the bottom of my canopy, hiding all of the electronics under it from the direct sunlight.

[Jurgen Heilig]

	Quote: Originally Posted by lazun
	You didn't read correctly then. 1:47 Rx 115*F (under shield) lifted shield slightly, not letting sunlight hit receivers and read temperature of right receiver only 1:49 No temperatures read put canopy on aircraft 1:53 Rx 135*F receiver failed Moved plane into shade, took off canopy, read temperature of receiver at 135 degrees F. Let it cool on its own in shade and receiver began working again at 108 degrees F.

Well, if you keep changing the story:

http://www.flyinggiants.com/forums/443621-post52.html

Excerpt:

We moved the aircraft into the sun and in 5 minutes one receiver failed. Its temperature read at 164 degrees F about one minute later, the other receiver failed at 165 degrees F.

We did the test a second time starting in the shade with the receivers being off and their temperature cooled down to 97 degrees F. At 1:03 pm with the temperature at 97 degrees F we turned the receivers back on. We put the aircraft in the sun. At 1:08 pm the temperature of the receiver case rose to 163 degrees F and one failed. The second one failed two minutes later at 1:10 pm at 165 degrees F.

Even if it fails at 135°F, it may still be outside the spec, because we don't know the Futaba rx specs.

Jürgen

[Woketman]

Why is everyone saying that Futaba is working on it? Over in the R/C Universe thread Bax says something like "they have only known about this for two weeks, give them a chance"! It would take me about 3 hours in my garage with a heat gun to try 10 different 6014 receivers and either confirm or prove false this temperature sensitivity theory. It should take Futaba less time.

They have had plenty of time to test & issue a statement that either there is or is not an issue. Not looking for a cure that fast, but at least they need to make a definitive statement NOW!!!

[lazun]

	Quote: Originally Posted by Jurgen Heilig
	Well, if you keep changing the story: http://www.flyinggiants.com/forums/443621-post52.html Excerpt: We moved the aircraft into the sun and in 5 minutes one receiver failed. Its temperature read at 164 degrees F about one minute later, the other receiver failed at 165 degrees F. We did the test a second time starting in the shade with the receivers being off and their temperature cooled down to 97 degrees F. At 1:03 pm with the temperature at 97 degrees F we turned the receivers back on. We put the aircraft in the sun. At 1:08 pm the temperature of the receiver case rose to 163 degrees F and one failed. The second one failed two minutes later at 1:10 pm at 165 degrees F. Even if it fails at 135°F, it may still be outside the spec, because we don't know the Futaba rx specs. Jürgen

I am not changing the story. You still do not understand. They fail as low as 130!!!

[reyn3545]

Fast Forward this conversation a few weeks... Futaba finally speaks... I'm sure they'll announce that the maximum operating temp for their receiver is somewhere around 50 degrees celcius... 122 degrees Fahrenheit. It will be the owner's responsibility to take whatever steps necessary to keep the receiver below this threshold.

OK.. now what do we do? As long as there's air flowing across the surface, the heat should be taken away. On the ground, however, we're going to have to take some precautions!

[lazun]

We do not know what the exact temprature of the IC. All we know is that the case of the RX is 130-165 degrees when it fails. I would have to say that the inside could be slightly cooler than that (shade barrier effect). So we do not know. We see it failing in 85 degree weather. Well within the limits. It is also happening to ALL the Futaba 2.4 RX out there with the same IC in it!!! The car guys as well (they do not mind too much since they just go get there car)!! So it is not the setup or a particular RX. It is all the RX with this 2.4 IC that will fail.

Back from SEA-TAC. There's Mt Rainier!!

[1bwana1]

	Quote: Originally Posted by reyn3545
	Fast Forward this conversation a few weeks... Futaba finally speaks... I'm sure they'll announce that the maximum operating temp for their receiver is somewhere around 50 degrees celcius... 122 degrees Fahrenheit. It will be the owner's responsibility to take whatever steps necessary to keep the receiver below this threshold. OK.. now what do we do? As long as there's air flowing across the surface, the heat should be taken away. On the ground, however, we're going to have to take some precautions!

I hope Futaba is a better company than that!

[Woketman]

Why do we have to wait a few weeks? Why have they not made a statement already? It has certainly been enough time to determine if this is real or not.

[Mithrandir]

	Quote: Originally Posted by Woketman
	Why do we have to wait a few weeks? Why have they not made a statement already? It has certainly been enough time to determine if this is real or not.

You might be assuming the problem is only a temp issue... this could be a problem that involves other issues that are not immediately apparent...

My company fully characterizes and qualifies our avionics and fuel systems to whole plethora of altitudes and temps.. it takes months... testing takes time if you want good data that tells the whole story.

[Woketman]

I agree. To fully characterize the exact issue down to the smallest detail would indeed take serious time. To get three guys to take ten 6014 recievers out into the lab, attach themocouples, raise the temp and see if they cut out below 180 degrees F would take less than three hours. That would at least validate that there is a thermal issue and they could say "yes, there's an issue. We are working on it". That is a LOT better than keeping us in the dark!

[ferocious frankie]

Has everyone read this on Futaba's site:

"Some battery back-up devices might have difficulties with the lower operational voltages as well, although they might not appear to initially. One such device functions perfectly on the ground and during a range check, yet when the operational temperature reaches 50° C (122° F), the device actually requires 2.8 Volts in order to function properly. As such, the servos will cease to operate properly."

Just something I found that might help some of you guys.