Letter (E-mail) to Great Planes:
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I bought one of your Great Planes Electrifly C-50 "Brush" Electronic Speed Controller with BEC. The device is connected to a HITEC 555 dual conversion "HITEC SHIFT" receiver and the motor is a KYOSHO ENDOPLASMA 16-T "Brush" R/C Truck Motor in a GREAT PLANES GD-600 Gearbos with 3.8:1 ratio and the motor was configured exactly how your product instruction booklet asked for the setup. This setup flys with the 8-Cell, GP-3300mAH, Ni-MH battery packs and I always measure the voltage before flight.

I have flown my R/C model (SKY RAIDER MACH-II, Low Wing Sport Trainer by WORLD MODELS) for 20 flights now and yesterday, July 18th, 2004, I experienced two unplanned CUT-OFF. Both in-flight and I could not recover the throttle after resetting the throttle. Fortunately, the flyer is an experience R/C flyer and the model has lots of wing area and low wing loading that the landings were not eventful and without damage.

I have been troubleshooting and it seems that your ESC is defective since my setup being that the motor is in a gearbox (GREAT PLANES GD-600 with 3.8:1 ratio) and the APC "E" 11 X 8.5 prop, it only pulls 33 AMPs at Wide Open Throttle. After landing the second time, I was able to re-start the motor and as soon as I reached close to half throttle it gave me a "CUT-OFF" once again without any recovery.

I just talked to your Eddy of Customer Service and I have decided to return this item to the Local Hobby Store for a store credit and going to get the CASTLE CREATIONS ESC for my setup.

It is unfortunate that you advertise a product saying it can withstand 50 AMPs "CONTINUIOUS MAX" on the packaging and advertisement ad's and really the device can not withstand no more than 40 AMPS for just a short burst mode. The Local Hobby store "WARNED" me about your C-50 product not being able to withstand the rigors of 36 - 40 AMPs but, I just could not beleive that a company with your reputation would actually put a product out knowing this so, I bought it to my dismay and doing so with the possibility of damaging my model or worst yet hurting someone while the model crashes!

I hope that you replace this C-50 "Brush" ESC with one that really can handle 50 AMPS continiously!

Here's the thread on my SKY RAIDER MACH-II that had the unfortunate experience with this product.
https://www.rcgroups.com/forums/show...79#post2406579

Thank you for your time and attention!
Carlos

Has anyone had a problem with a recent version of this C-50 Brush ESC?

I had one about a year ago that burned out after 30 or so 10-15 minute flights on a geared endoplasma with 7 cell GP3300 battery, probably drawing 30 amps peak. I won't buy any other GP ESCs. I've had much better luck with Astro Flight, Jeti, GWS, and Castle Creations ESCs.

Originally Posted by BrianRickman

I had one about a year ago that burned out after 30 or so 10-15 minute flights on a geared endoplasma with 7 cell GP3300 battery, probably drawing 30 amps peak. I won't buy any other GP ESCs. I've had much better luck with Astro Flight, Jeti, GWS, and Castle Creations ESCs.

Thanks! I am in the same belief that you try a company's product and if it does not perform how they say it does then, forget future considerations. I wish they label that C-50 as a C-30!

Carlos

Carlos

I have been very happy with my Great Planes ESC's. I think you will find as many issues with others products - Just ask Gary Wright, I saw a post where he switched to the Great Planes ESC in a 50 amp application after another controller failed. I think in some cases they may be getting a bad rap with over-amping. I should not speak for Gary and I don't run anything over 40 amps.

I don't doubt that yours failed (others reported theirs have failed as well) but I have yet to have an issue with mine (I have 4 GP escs) and have pushed some of them very hard especially in the BEC areas (4-5 servos and max cell counts!).

I know the 50 amp can handle more than 30 amps - for sure. I don't think they are being fraudulent in claiming 50 amps. Cooling is key for all of our esc's. Hang them out in the air and see if that makes a difference.

The other thought is to get a Griffin 55 with 80 amp serge. I know the CC controllers are not underrated.

Just had to report my experiences.

Mike

I lost a plane (Sport-E-Stick) because of a GP 50 ESC. It burnt out after only three flights on an endo geared setup with 10 GP3300 cells. I am pretty much stuck on CC controllers now. They work great and fantastic service.

Thanks guys!

My final thought on the "C" series is that I like them, but I found that their amp rating is worthless from the C-20 on up if they have no direct airflow. Mounting them outside the aircraft has often allowed them to go over their amp rating especially in winter.

Originally Posted by AMTJIM

My final thought on the "C" series is that I like them, but I found that their amp rating is worthless from the C-20 on up if they have no direct airflow. Mounting them outside the aircraft has often allowed them to go over their amp rating especially in winter.

Okay,

Seems there's a lot of concern over airflow and cooling....

If you go to my SKY RAIDER MACH-II thread you will see that I opened up a large hole at the bottom of the Firewall and middle fuel hole as well for lots of airflow. The batteries come down luke warm and I suspect that ESC is having a nice bahama breeze of a time up there while in flight.

There's just no reason for a advertised product to be rated at 50 AMPs continuious use and be below 40 Amps and have this type of shut down without the possibility of recovery by resetting throttle unless of course it maybe infact a over temperature shutdown of the ESC.

Carlos

Definitely airflow, no cooling tubes, vents or holes. I do have one of my ESC's in the intake of the T-33 and it does great, other than that they all get mounted on externally on the fuse. One of my C-50's I had on a Twin Jet burned up in flight, it only ran at 18 amps on 8 cells. Once moved outside the plane, a C-20 did fine. I have had other similar incidents, but in most cases the BEC's survived and it was just a thermal shutdown of the motor controller, so I was able to land. The only time I have gotten a problemed internally mounted "C" series that was shutting down to not shutdown, especially here in the desert, was when I attached some clip-on type computer transistor heat sinks that fit this ESC perfectly.
By the way, I also have to mount most of my Jeti brushless ESC's outside the plane too, so it's not just the the Greatplanes product. In most cases the only run at 1/2 the rated amps, but they also had thermal shutdowns. In some cases I have been able to get away with internal ESC's by using vents, external ESC's on hotliners is a crime.

ATMJIM,

You hit it on the nail(s)

The Electrifly C-50 by Great Planes do indeed have a thermal cut off built in and it does cut off the motor until the power transistors cool off. Take a look at the last sentence of last paragraph.

Dang, what?? Do you have to hang these ESC's outside the model to get cooling or what? I Guess so!

Anyway, I got rid of it today......

Now take a look at what GREAT PLANES say about an optional receiver battery thereby, disabling the BEC in case you have so called High Powered Servos....

What they don't tell you here is that if you have a motor that surpasses a certain amount of AMP draw this effect holds true as well !!!!

Dang, doesn't anyone out there make the GOOD OLD BRUSH ESC's without all this nonsense!

Dear Mr. Castillo:

I hope you can help me in my delema.

I have purchased the CASTLE CREATIONS GRIFFIN-55 ESC yesterday after a bad experience with the Electrifly C-50.

Once I got home and looked at the GRIFFIN-55 instructional booklet, I noticed that my setup would require disabling the BEC since my Kyosho Enoplasma draws about 37 AMPs at Wide Open throttle. I was pretty dismayed to read this in BOLD under section 2..3 and would hope to find an ESC that can withstand the rigors of my setup without disabling the BEC.

Please visit my thread and reply to my delema.
https://www.rcgroups.com/forums/show...65#post2415665

The posting of interest is at the bottom of page 16.

Thank you for your asistance!

Howdy G-Man! I was wondering if you experienced the same symptoms with the C-50 in the SRM1? Your postings have motivated me to purchase the same setup for a Falcon Mark II that I'm rebuilding, so I obviously have a vested interest in how this thread turns out.

TIA!

Dave

"Flying is optional, landing is mandatory"

Have to chip my 2 cents in. I've got a Great Planes C20 that I used in a converted Cox EZ-Bee, with a Trinity P2K, direct drive. I popped a few 20 amp fuses between the 6 & 7 cell car battery packs that I was using and the esc, then I started using 25 amp fuses. Plane flew like a powered rock, but even though I managed to blow a few 25 and 30 amp fuses, the C20, which was outside the cowling, never failed me. I did a lot of bench testing with the C20 and a C30, they never failed me and I pushed them stupidly at times. This was the stuff available maybe 2-3 years ago, current production may not be as good.