I dealt with this issue first hand.
This is a text book issue.
Sales over Safety.
The right thing to do would of been to recall the CB200.

More thoughts from an outsider: Are these tests failing within spec limits in a fair test or beyond with abnormal setups? For a product to meet spec, it has to be able to live beyond that spec. In my automotive field if a lift is rated at 1 ton, and you test it and it fails at 1800 pounds, it failed to meet spec and OSHA will own the manufacture if it's not dealt with. But to test it to 2500 and have it fail is a fair test even if it doesn't meet your personal needs. (shoulda bought a bigger lift, no fault of manufacture) In this case of the CB200s, are they failing beyond 74c internally considering ambient as well as load temps? If so, they live up to spec and the setup is a question even if the setup is the reason for generating the >74c temps. If not, and they "open" at 73c or less, it's a design flaw or component quality inconsistency which to be ignored is poor support. Are we clear on which side of the fence this testing sits?

Originally Posted by buckeyeflyer

It did have one in it Joe. I think I posted that awhile back or Jeti is feeding Ed info to post.

Yeah, right! Page 31, #462

Further testing of heat related to poly fuse failure on the CB 200. Looks very familiar to Buckeyeflyers crash video posted earlier.

August 13, 2019 (0 min 33 sec)

For some hard data on Buckey's post:

Savox 2290 Max Amps Draw = 7 Amps and goes down to 6.xx at stall.
Savox 2290 Test:

Savox 2290 (1 min 34 sec)

Is 7.0 amps within the design parameters of the CB200?
Now what's missing is the temperature "ambient" of the day, and temperature inside the airframe.

Please read the description posted in the video to further clarify the testing.

Originally Posted by BuckeyeBigBird

Further testing of heat related to poly fuse failure on the CB 200. Looks very familiar to Buckeyeflyers crash video posted earlier.
https://youtu.be/-UfysezqO7I

This video is certainly not over the Temperature limitations of the CB 200 as it's not flown, the engine is not running generating heat, the temperature within the airframe is ambient.

The only thing causing the tripping of the Polyfuse is the load on the servo. Depending on what servo it is, will determine the amperage draw.

As I posted earlier, the result of the Polyfuse tripping and resetting is the "Out of Sync" behavior of the surfaces.

Hard to dispute this video.

big power servos on a CB200 with a hot day is very bad.......
we concluded that....
Each servo output on a cb200 is protected by a thermal fuse.....when a servo stalls or is worked hard it draws high current then the fuse shuts off the servo power protecting the rest of the system.....when it cools down moments later it then resets.
Trouble is this is a 2.6amp continuous fuse and a HBL380 pulls 7.6amps when changing direction fast with no load or under high load during high speed full deflection or rifle rolls etc continuous current will be high.....with the CB200 running cool at under 50degC this is fine.......but when the cb200 is at 70degC its very bad as this next video shows.
Inbetween 50 to 70degC i would say its a grey area.
As the temp of the CB200 increases then its threshold to blow drops.
Jets seem to be ok as the cb200 stays cool....but 3d planes in the sun with hot air blown down the tunnel....not good
Our CB200 in the extra reaches 31deg on an easy flight on a cold december day where the temps were just 8deg.
In the uk we are seeing well over 50 deg on warm days. On a hot day not sure....still checking log files.

August 13, 2019 (0 min 33 sec)

Originally Posted by BuckeyeBigBird

Please read the description posted in the video to further clarify the testing.

Just posting your comments here for easy access.. Seems like the CB200 is not intended for anyone flying 3D with powerful servos.

A bulletin should be sent out to all CB200 users to indicate that.

big power servos on a CB200 with a hot day is very bad.......
we concluded that....

Each servo output on a cb200 is protected by a thermal fuse.....when a servo stalls or is worked hard it draws high current then the fuse shuts off the servo power protecting the rest of the system.....when it cools down moments later it then resets.
Trouble is this is a 2.6amp continuous fuse and a HBL380 pulls 7.6amps when changing direction fast with no load or under high load during high speed full deflection or rifle rolls etc continuous current will be high.....with the CB200 running cool at under 50degC this is fine.......but when the cb200 is at 70degC its very bad as this next video shows.

Inbetween 50 to 70degC i would say its a grey area.
As the temp of the CB200 increases then its threshold to blow drops.

Jets seem to be ok as the cb200 stays cool....but 3d planes in the sun with hot air blown down the tunnel....not good
Our CB200 in the extra reaches 31deg on an easy flight on a cold december day where the temps were just 8deg.

In the uk we are seeing well over 50 deg on warm days. On a hot day not sure....still checking log files

Originally Posted by hpdrifter

Yeah, right! Page 31, #462

Yes sir. I give you credit. Your working really hard to discredit the findings.

Originally Posted by camss69

My testing shows my plane with the CB200 and MKS servos flys fine.. that’s what my test equipment shows, for a couple years now. I’m interested in what you have to say but I want to know the details of your testing so I’m asking questions.

Flying IMAC, jets or flying circles maybe OK .....now go out and do some hard rolling loops with 45 degrees of travel on each surface or any other hard maneuver. Those servos will be pulling 10+ amps each in no time.

PS, take garbage bags with you just in case

Originally Posted by camss69

Ok so I just watched part of one of the videos and I’m confused. I don’t think your MFJ-852 AC Line Noise Meter is telling you what you think it is.....or maybe it is I don’t know. Is it picking up RF yes, but in the 135Mhz range if I’m reading the pdf on the manufacturers website correctly.

It's picking up broad range. People get hung up on the exact range. You mean to tell me that if your ignition craps itself and starts emitting RF that it's in an exact range to bring your plane down......fake news!!!

I have the same meter and have diagnosed bad RX, bad servos and two bad power expanders. Here's the real kicker to make you think.....I diagnosed a bad extension on a satellite on a spektrum system. Changed extension, plane was clean. Chew on that, you think it was in a specific range.....highly doubtful.

One of the power expanders that I found was a certain one from a company in Australia. Actually crashed my plane and I was able to re-create brown outs using high current (MKS) servos. I sent my expander, servos and RX to the company for testing and low and behold.....few months later they have a new power expander on the market.

The meter WORKS, period.

Originally Posted by buckeyeflyer

Yes sir. I give you credit. Your working really hard to discredit the findings.

Buckeyeflyer, would you be so kind to give Joe the following info? It appears to me that he is suffering from same kind of mental block.



CB200 is a medium duty servo interface. It's rated for continuous current of 15A TOTAL and 90A pulse (Joe thinks it's a 15A per servo). The operational temp range is between -20C and +75C.


According to manufacture specifications, the poly fuses 260/12 will trip between 3.5A at 80C and 5A at 22C.


Considering this numbers, it's pretty obvious to any average intelligent person that you can not use CB200 safely in an airplane with servos drawing more than 3.5A continuous (per servo).


Thank you, appreciate it. ed

Originally Posted by hpdrifter

Buckeyeflyer, would you be so kind to give Joe the following info? It appears to me that he is suffering from same kind of mental block.

CB200 is a medium duty servo interface. It's rated for continuous current of 15A TOTAL and 90A pulse (Joe thinks it's a 15A per servo). The operational temp range is between -20C and +75C.

According to manufacture specifications, the poly fuses 260/12 will trip between 3.5A at 80C and 5A at 22C.


Considering this numbers, it's pretty obvious to any average intelligent person that you can not use CB200 safely in airplane with servos drawing more than 3.5A continuous (per servo).

Thank you, appreciate it. ed

Being said "intelligent" person yourself you do realize that you can merely "wiggle the sticks" on the ground with a plane full of MKS380 or 599 and get up to 5 amps per servo.....correct? Maybe you didn't realize this information?

Been there, done that and that's why I no longer use them. Then when those same servos start to jitter on the ground (on planes with large surfaces) after they start to get older they draw even more amps and also start to emit RF as discussed before.

Now being a self proclaimed intelligent person you start to see the problem here right?

Someone needs a more robust system instead of telling all their customers they are idiots.

Originally Posted by 3D Wiley

It's picking up broad range. People get hung up on the exact range. You mean to tell me that if your ignition craps itself and starts emitting RF that it's in an exact range to bring your plane down......fake news!!!

I have the same meter and have diagnosed bad RX, bad servos and two bad power expanders. Here's the real kicker to make you think.....I diagnosed a bad extension on a satellite on a spektrum system. Changed extension, plane was clean. Chew on that, you think it was in a specific range.....highly doubtful.

One of the power expanders that I found was a certain one from a company in Australia. Actually crashed my plane and I was able to re-create brown outs using high current (MKS) servos. I sent my expander, servos and RX to the company for testing and low and behold.....few months later they have a new power expander on the market.

The meter WORKS, period.

LOL, Ok, you’re seeing what you want to see.