CC HV120 - Reprogrammed - Failed!

[fa18frog]

Looking for a little feed back and to share a recent discussion with Castle Tech Support.

I fly a TREX 700 F3C which is flown solely to practice the AMA Sportsman Sequence - which puts a relatively low demand on the helicopter. In researching the best setup for the helicopter there were many discussions about lowering the head speed which lead me back to the instruction manual and the recommended head speeds for Governor Mode. I watched the video in the Castle Support section that covered programming in Governor Mode (In the video it specifically addresses lower head speeds - 70% throttle - for competition) I reprogrammed the ESC with the speeds recommended in the manual 1450/1900/2000 RPM. If you go below or above these numbers the Castle Link gives a warning. All of the above numbers were reported as "good".

I took the helicopter out and immediately noticed the benefits of the lower head speed during the hovering portion of the sequence. It was smooth and responsive and I was quite happy with the change. That lasted a day and a half - three flights if I remember correctly. The third flight ended with a flaming auto-rotation with the ESC ON FIRE!

My initial thought - Sh!t Happens!! Its not the first motor or ESC that has failed on me. During the post flight discussion with the local helicopter guru I mentioned that I had lowered the head speed to 1450 (70%). Right away he said that was too low and probably caused the ESC to overheat. The recommended range was 89-96%. I thought to myself certainly the Castle Link would warn me if I was operating outside of a safe parameter.

Monday, I called Castle Support sure that they would say 1450 was within limits since a low head speed was mentioned in the video and the Castle Link said 1450 RPM was "good" Much to my surprise the support tech said that operation outside of 90-95% could cause heating issues with the ESC. I went from calm to infuriated in a heartbeat. I was looking at $500+ dollars of damage to my helicopter and the Castle Link gave me no warning that heat could be an issue. I asked him why the programmer would allow me to program in a head speed that could cause an issue and call it "good" No good answer.

Since the ESC is just over a year old it is not covered under the warranty and as the tech said he can't be sure that reprogramming the ESC caused the issue. And while that is certainly true it seems awful suspect that the ESC smoked shortly after I reprogrammed it and the tech himself said that the low head speed could cause heating issues.

The support tech said that I should have monitored the ESC temp closely. I have flown this helicopter for over a year without incident and I reprogrammed the ESC within their published limits. There is no warning that operating outside of 90-95% needs to be monitored closely. On initial setup of airplanes and helicopters I check to make sure everything is within limits: watts, current, temps. After reprogramming the ESC If the temp needs to be monitored closely again it's not "GOOD"

I have had good experience with Castle products but this has severely shaken my confidence and the customer service experience left a lot to be desired. A $2500 helicopter is a bit much to entrust to a programmer that my or may not be giving worth while information. Perhaps the tech is right and it failed for another reason. Its suspect to say the least and it's doubtful I will be a Castle customer in the future.

[Mercuriell]

I'd be surprised if it was low HS that caused the flame up. CC ESC are one of the few that have automatic freewheeling that is supposed to (and does mostly) prevent overheating.

I think generally HS is best determined by pack voltage, motor kV and gearing than running the ESC at low throttle % where the ESC has to chop up the power and dissipate as heat instead of porting to the motor.

I think it bad luck in your case and probably a component failure. Every ESC brand suffers failures , some, like Kontronik go to extreme measures to make sure their ESC do not catch fire and this can result in heli loss due to sudden shutdown.

Hope you're back in the air again soon!

[fa18frog]

I do not discount the fact that there could have been another cause. It seems suspect. More than one person mentioned heating issue at lower RPMs after the fact - including Castle Tech Support. I have a 700 FDC waiting to be tested with a CC HC120 programmed per the manual and outside of the 90-95% range. I am lacking confidence in the ESC. Not because one caught on fire but because Tech Support basically said that the Caslte Link info is guidance and now I have to play electrical engineer.

I have been researching other ESC options. In my research CC ESCs do not have automatic freewheeling. Scorpion, Kontronik and another brand do and that may be a deciding factor.

James

[Mercuriell]

CC have automatic but passive, not active freewheeling which KT, YGE and Scorpion do. I guess that could explain your ESC failure at low,throttle and I agree some warning would be appropriate in the Castle Link.

In fairness to CC, such scenarios have been rare in the past as most have tried to squeeze the last drop of power from their setups but I guess with the increased interest in low speed flying this may occur more often!

There is a wealth of ESC info in this thread https://www.helifreak.com/showthread.php?t=443322

[JohnTC02]

FWIW.

I have the 700v2 F3C which has been converted to FBL plus I fitted a 10t pinion, been flying this at a head speed of 1100rpm for over a 220 flights and I'm getting 14mins per flight.

Zero issues with the stock ESC, temps get to around 140f as does the motor.

[LizardMan]

My 700E DFC uses a 120HV with stock gearing 112/12 and 690mm blades.

The ESC is operated in governor mode at 1700/1850/1950RPM. I don't need higher HS. Longer flight times are more important to me than raw power. Lower head speeds appear to help avoid tail hum issues.

I download ESC logs after each trip to the field. 1700RPM noticeably increases ESC temp, but not enough to exceed 175F. There's less difference between 1850 and 1950RPM, but 1850RPM generates more heat and ESC temp increases for a longer period of time before levelling out about three minutes in the each flight.

High loads (pitch pumps and full collective FFF) cause a sharp increase in ESC temp at 1700 and 1850RPM too.

Did you look at your ESC logs after reprogramming the governor?

[fa18frog]

My issue really isn't that the ESC failed. In fact, if the low rpm issue wouldn't have been brought up at the field and all but confirmed by tech support I would have bought another CC ESC Monday morning and wouldn't have given it a second thought. My issue is that the parameters set as "good" on the Castle Link fall well outside of the 90-95% recommended by Tech Support. Active Freewheeling does expand the RPM range and that may better suite my needs. So the question is do I buy another CC ESC and trust the Castle Link or move on to another brand that better fits my application.

Dropping the motor gear pinion to 11t or 10t would help drop the RPM as well and keep the ESC in better range.

Bottom line. If there is an issue with temperature - the Castle Link should provide a warning. If I go above 2100 or below 1450 it gave me a warning and I adjusted accordingly. If proper operation is 90-95% then programming outside of that range while perhaps not red (Danger) should at the very least be yellow (Caution) to let you know to monitor temps very closely.

James

[fa18frog]

Unfortunately didn't get a chance to download the ESC. I've been flying the helicopter for over a year and it gets plenty hot here in FL during the summer and I have never had a temp issue that concerned me. Perhaps, I am being naive but I was using numbers from the Align Manual. I plugged those numbers into the Castle Link and each one said "good" so I wasn't really expecting any issues. The Sportsman Sequence isn't that demanding on the system. Three hovering sequences followed by a procedure turn, stall turn, loop and roll and then a landing. ESC flamed out on approach to landing.

Nothing really caught my attention. Batteries were barely warm and the remaining battery life went from 20-30% to 40-50% so I mistakenly assumed I was putting even less demand on the system. I have a TREX 550 (Talon 90 with no logging) that I fly more aggressively and the motor, battery and ESC get noticeably warmer but in the year I have flown it Ive never had an issue.

I used the Align Manual which gives the recommended head speeds. CC's instructional video discusses flying at 70%, Castle Link says "Good" but Tech Support says 1450 (70%) is too low and can cause an issue. I have a brand new 700 DFC and I set it up as per the manual and Castle Link is "Good" with the head speeds. So am I good or not. Hard to be confident in a product with mixed messages!!

James

[kthane]

Castle do not fair well at partial throttle. As mentioned ealier castle does not have active free wheel. YGE and Kontronik are a better fit for what you want to do with the heli. Castle works well for me, but i think you need to change brands.

[fa18frog]

Researching ESCs over the past couple of days I have come to the same conclusion. The link supplied by Mercuriell was quite helpful in understanding the function and limitations of speed controllers in helicopter use. Had I read the articles before hand I would have been much more hesitant to lower the head speed. And had I chose to do so I would known to watch the temp of the ESC very closely.

But here's the rub. Many folks already know that the CC ESCs don't handle lower RPM settings very well due to the lack of Active Freewheeling. This includes the folks at Castle. So it begs the question, if you know that temperature will become and issue why would you let the consumer operate in an RPM range that is known to cause an issue. If you exceed the parameters set in the software the number turns red and warns you not to select that RPM. Tech Support recommended 90-95% to avoid heating issues. Why then is the lower RPM range that is know to cause an issue not set up as a warning or at the very least some kind of caution. The Align Manual, Castle Link and Castle Instructional Video all list lower as RPM as OK. It's not OK. I followed the manual recommendations, watched their video and programmed within the limits set up by the Castle Link software. I would prefer no information to bogus information. At least I would have known to proceed with caution. This lesson in ESC operations cost me between $500-$600 and I was lucky, It could have easily been a total loss.

James

[xokia]

Originally Posted by fa18frog

Many folks already know that the CC ESCs don't handle lower RPM settings very well due to the lack of Active Freewheeling. This includes the folks at Castle. So it begs the question, if you know that temperature will become and issue why would you let the consumer operate in an RPM range that is known to cause an issue. If you exceed the parameters set in the software the number turns red and warns you not to select that RPM. James

Yea they could do a better job here. CC ESCs do not handle setting below the 90-95% range very well. They will do it and regulate head speed fine but the temperature rises very very quickly. They could easily warn you that it could cause excessive heating.

CC is the HK of ESCs though so you can't expect anymore out of them then you would from a HK esc. Ironically a HK ESC would have likely been fine they have active freewheeling.

[piledrive1]

My ice 2 120hv went up in flames on my 700 pro dfc today