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Author Topic: Timer and ESC programming  (Read 587 times)

Offline John Witt

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Timer and ESC programming
« on: June 21, 2009, 04:38:50 PM »
I seem to have painted myself into a corner. I have a CC Phoenix 45 ESC and a Ztron timer. When I initially ran this in simple mode with the 3 blips programmed, everything worked as advertised.

With the new motor in my plane I want to keep the RPM down below 11,000 to about 9600, so I used the "Set RPM" mode in the ESC. Apparently in this mode, the ESC maintains the RPM regardless of the throttle input provided by the Ztron, so the ESC doesn't see the throttle blips. Is this a correct interpretation, because the blips have gone away, it just turns off at the set time?

I tried running in "High Gov" mode and setting the start and end throttle setting with the Ztron. In this combination, the motor starts, then ramps up to full throttle for a few  seconds, then drops back to the setting that gives about 9600 rpm (32% throttle). Is there a way to get around this full throttle portion of the sequence? I hate to waste battery power for essentially nothing.

Or, is there another issue I'm not seeing?


John
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John Witt
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Alan Hahn

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Re: Timer and ESC programming
« Reply #1 on: June 21, 2009, 06:15:05 PM »
John,
I am not sure if this is the answer for you, but the reason you are not hearing the "blips" is that you might have a very slow throttle response setup on the Phoenix. This is not the governor gain parameter, but it limits how fast the ESC will allow the throttle to advance (or retreat)---primarily for the RC Helicopter guys where if the throttle is jammed fast, the gears could be stripped.

So try to let the throttle response parameter be set to a higher value.

As an aside, I really wish I could turn the "blips" off. As I have mentioned, I always use a "Talking Timer" that tells me exactly where I am in time. So when it tells me 1 minute is left, I know I better be in the middle of the clover (I always am!), and at 30s left the motor stops. Somewhere the blips do occur, but my throttle response is set to be slow, so I don't even hear it.

Even if you aren't always flying the pattern, having the time mark is even more important in my book. At least with the pattern everything is more or less determined, at least to the 5-10 s mark anyway. If you are fun flying, it is easy to lose track of where you are, so having the blips or the Taking TImer is an easy way to keep track of the time.
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Offline John Witt

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Re: Timer and ESC programming
« Reply #2 on: June 21, 2009, 07:22:49 PM »
Quote from: Alan Hahn on June 21, 2009, 06:15:05 PM
John,
I am not sure if this is the answer for you, but the reason you are not hearing the "blips" is that you might have a very slow throttle response setup on the Phoenix. This is not the governor gain parameter, but it limits how fast the ESC will allow the throttle to advance (or retreat)---primarily for the RC Helicopter guys where if the throttle is jammed fast, the gears could be stripped.

So try to let the throttle response parameter be set to a higher value.


Alan,

Are you using the Airplane or Helo base mode? The control line mode doesn't allow changing the throttle response parameter. If you are using the airplane mode what are the endpoints?

Thanks for the response. I figured someone had dealt with this. This forum is great.  %^@

John
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Offline John Cralley

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Re: Timer and ESC programming
« Reply #3 on: June 21, 2009, 08:38:03 PM »
John,

I'm using a Will Hubin timer (FM-2X) which he programmed for me so that the timer will cycle through the three set RPMs. I have it set to run up flight RPM (#2 Head speed - 50% to 99% throttle) then about 6 seconds before shut down it switches to #3 Head speed RPM (99%+ throttle) for a brief moment and then to #1 Head speed RPM (0 to 50% throttle) for six seconds.

My CC Phoenix 45 ESC is set for:
 #1 8500 rpm
 #2 9200 rpm (flight rpm)
 #3 10000 rpm

So at the end of a flight I get a brief spurt (10000 rpm) and then a lower speed (8500) then shut down. Since I am sport flying, this warns me the shut down is coming up. I have a talking timer (ah la Alan Hahn) but I usually forget to set or start it. LOL

Will's FM-2X timer also has a "stooge" mode (set by a micro pot) which will cause the timer to wait for about 30 seconds after the start button is touched and then go through the programmed sequence. This is ample time to walk out to the handle and be prepared for takeoff.
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Alan Hahn

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Re: Timer and ESC programming
« Reply #4 on: June 21, 2009, 08:46:24 PM »
Quote from: John Witt on June 21, 2009, 07:22:49 PM
Alan,

Are you using the Airplane or Helo base mode? The control line mode doesn't allow changing the throttle response parameter. If you are using the airplane mode what are the endpoints?

Thanks for the response. I figured someone had dealt with this. This forum is great.  %^@

John

John,
I'm using the CL governor mode. Are you sure about the throttle response factor? You might be right and I am just remembering the way it was before there was a CL mode.
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Alan Hahn

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Re: Timer and ESC programming
« Reply #5 on: June 22, 2009, 07:48:19 AM »
John,
I just checked. On my version of the CC software (v3.11), there is a quantity called "Head Speed Change rate. It says it governs how fast you can increase the throttle (but nothing about decreasing it). I have mine set for "Medium"or # 5, and on my Will Hubin TImer, I definitely feel the two "blips" --CC45A Phoenix ESC--(as a matter of fact, I almost make a landing--they are that long!). On my JMP-2 timer (and with a CC 35A ESC set to same "Medium") I don't feel the blips at all. It could be the JMP-2 blips are really short, or perhaps the 45A ESC is different in some way from my 35A ESC (I sort of doubt that).

Anyway you might change that quantity to "High" and see what happens.

I note that if I save the parameters to a txt file, there also is another parameter called "Throttle Response" which is also set to "5". You are right that it isn't there on the CL menu. I wonder if you choose the airplane menu and set it, whether it really does anything.

For now it does seem like a mystery!

Another detail---are you using the brake feature? If the ESC see's a zero throttle, then the prop is slowed down. Of course I am using the brake on all my CC Phoenix ESC's so that doesn't completely explain why my JMP-2 behaves differently from the Hubin timer--but again, maybe the Hubin timer has a longer blip period. I have my brake set as "100% (Hard)", the Brake delay at a minimum 0.3 s, and the Brake ramp as "Slow".
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Offline Will Hubin

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Re: Timer and ESC programming
« Reply #6 on: June 22, 2009, 08:53:24 AM »
John,
    Early on I found that the Phoenix High RPM mode and the Set RPM mode require different programming from the timer, because the RPMs in use in the High RPM mode are all in the half-throttle or less setting (=< 50%) and so a warning that works in the High RPM mode (reducing the throttle for a warning) will not work in the Set RPM because it just keeps it in RPM #1.
    So most of my timers are programmed for either one of the standard RPM modes or for the Set RPM mode. When programmed for the Set RPM mode (except for some custom programming such as for John Cralley's FM-2x), they allow the user to choose any one of the three RPMs by turning the RPM pot either fully counterclockwise, anywhere in the middle, or fully clockwise, and the program automatically choses a second at RPM #1 (if not in use for the flight) or RPM #3 (if #1 is in use for the flight). It is always a compromise between getting enough warning and getting power returned in time to escape if you're caught up high, but I've found that a 500 RPM change for that one-second warning seems to be adequate, for me, at least.
    One of my recent timers (FM-6a) does have a switch so that the user can choose between any governed/RPM mode and the Set RPM mode. There are two RPM pots on it so that any of the governed RPM modes (Simple, Low, High) can be used (since the full range of throttle inputs, from 1.0 ms to 2.0 ms, are available).
     This doesn't help fix your problem with a different timer (and I don't understand why you get a blip to full throttle), but should give some insight into the potential problems.
    Cheers!
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