Phoenix 35 ESC Preliminary Report

[skigolfmike]

I got enough info for my quick setup tonight to say I think this os going to work really well. I also have enough setup info to anyone else in the ballpark.

First of all, thanks to Finless for his Phoenix 85 video. That helped out a lot.

All I've done so far is to setup normal mode with the governor and play with the settings. I started by setting up the throttle in fixed heli mode, set soft cutoff and turned off the brake. I also set soft start to low. That worked OK and flew just fine with the existing throttle curves. That wasn't why I got this ESC, so I moved on to the next step, setting up governor mode.

First I tried low governor. That wasn't going to fly, 500 RPM head speed just isn't going to cut it. Back to the computer and I changed the programming to high governor. I was still low on soft spool and low governor gain with defaults on everything else. I set the head rpm by setting a flat throttle curve at 0%, put the stick at 50% and started bumping up the curve. I got to 50% pretty quick, but it wasn't happening and I was about to give up on it. Then it started to slowly wind up. I let the rpm stabilize and took a reading. I ended up at 65% throttle.

So now I set my throttle points in normal to 0-65-65-65-65, spool it up at half stick and see what happens. The spool up took forever since I was still on low for soft start, but it stabilized and I lifted off. Normally at lift off the rpm picks up a bit, this time there was no change at all. It actually hovered quite nicely and it's a little less sensitive to stick movements than before. This is as far as I got before I ran out of daylight plus it started to rain. (Like we need more of that!)

I played with it a little more in the basement and I actually got to experience the soft cutoff. Oops! Fortunately, the ESC kept me from becoming a member ruining a battery or even becoming a member of team taco. Thankfully, my TP610c changer brought the battery back. After changing to a fresh battery and doing a few run-ups, I found the high setting on soft start works the best. Also setting the governor gain to medium works well too. I also set current limiting to disabled. I had it set to insensitive, but I thought that might be causing some problems. More on that later.

What I want to do next is finishing setting up the normal curve. Then I'll get an idle-up curve set. I'm guessing for idle-up I'll be in the 75% range. Then I'll fly it come and see how it does. So far it looks promising.

Here are some pics of the installation:

Pic 1 is a view of the speed control and the ccbec.
Pic 2 is a view of the right side of the heli
Pic 3 is a view of the ESC from the left side
Pic 4 is a view of the rats nest I have for wires at the back of the heli.

[skigolfmike]

I just got in two flights this morning with the Phoenix in governor mode. All I can say is WOW. This ESC is great.

Head speed just doesn't vary. Punch-outs are unbelievable. The heli is more stable than ever. IMHO, this is a very good upgrade for the B400.

I didn't shoot any video because it started to rain again. I did get a full flight in to time battery life. I got 8:50 w/ my TP2100s, which will probably translate into 8:00 safely in normal and 6:00 in idle-up.

It was pretty cold out, 38*F, and I froze my hands off. Motor was at 65*F, ESC at 45*F and battery at 100*F at then end of the flight.

I still have stuff to play with. I'm running low timing advance, I may change that to standard or medium, which may help since the motor on the B400 is a pretty high kV motor and high kV motors usually need more timing advance.

When I get it figured out out I will go shoot some video.

Just finished recharging the battery. 2169mAh into a 2100 for an 8:50 flight. If 80% of capacity is what to shoot for, then I really should be looking at 1700mAh on recharge, That works out to 6:55 to be safe. ((530sec/2169mAh)*1700mAh = 415 sec) With the 1800 E-Flites it would be ((530/2169)*(1800*.8) = 351sec or 5:51. That hover and normal flight, not 3D. 3D will be less.

[skigolfmike]

I said I'd shoot some video of this setup when I got the chance. Even a little snow didn't stop me.

uKOUN883QTU

A couple of notes: I noticed a couple of surges when it was finishing spooling up. Once I lifted off those were gone. The biggest thing I noticed is the head speed stays the same after lift off (used to pick up, see earlier videos) and also flying around. It's super stable in hover now too.

To clarify about the throttle hold switch: It's set at 3% throttle, so if I shoot any autos and have to bail, I won't have to go through spooling up again. The procedure is turn on the radio, turn on throttle hold, plug in the heli, get the initial speed control tones and let the gyro arm, put on the canopy, set the heli in place, turn off throttle hold and let the ESC arm and go fly.

Finless Phoenix 85HV setup videos (http://www.helifreak.com/showthread.php?t=36194)

[skigolfmike]

YeeHaa! It's really neat. Here's what I ended up with.

################################################## #####
# Castle Link Data File
# Created: Monday, March 24, 2008
# Do Not Edit This File By Hand
################################################## #####
Motor Timing: Low Advance
Hex55: 85
Brake Strength: 0
Throttle Response: 2
Brake Delay: 1 sec
Cutoff Voltage: Auto Li-Po (*)
Throttle Type: Heli: Governor High
Direction: Forward (*)
Current Limiting: Disabled
Governor Gain: 33
Cutoff Type: Soft Cutoff
Motor Start Power: 59
Brake Ramp: Super Slow
PWM Rate: 13khz (*)
Spool-Up Speed: 10

Throttle is 65% normal and 75% for idle up. Which gives 2460rpm and 2750rpm respectively. It's flys smooth, worth the effort to get it setup.

In experimenting tonight I found that I picked up about 300 rpm in low advance over standard advance. This is a good thing as the motor will run cooler than standard advance and I'll use less current. The biggest thing I had to play with the the governor gain. Med (50%) was to much and the tail kicked a little about once every 2 sec. Low gain was too low and there was a tendency to yo yo a little, plus the tail had a slow oscillation too. I ended up at 33% there.

Things to get use to: You can set throttle hold at 0 throttle and have the throttle curve flat and just throw the switch, or you can set the normal curve to 0-N-N-N-N (In my case 65%) and just push up quickly to half stick. In either case, it takes about 10 sec for it to spool-up. Once it's wound up it doesn't change unless you change to another throttle curve with a different throttle percentage.

Now all I need a little video of it flying around to post here.

[skigolfmike]

I got to do a little more playing around with the setup and I learned a few things. I have it working really well at this point. I feel there is still room for improvement though.

I got out Tuesday night with the lap top and I ran through the whole sequence again. Went back into fixed heli mode and looked for the headspeed at 75% and 85%. The head speed was 2400 rpm for both. In fact, at 75% throttle and above the head speed didn't increase. I tired low, standard and high advance and I got the highest rpm in low advance.

Then I switched it back to governor high mode to set the head speed. I got 2400 rpm at 65%. However, I got 2750 rpm at 72%, Above 72% there was no increase in headspeed. In flying the heli I ended up at 68% throttle for normal 2600 rpm and 72% for idle up 2750 rpm. In my opinion I think the headspeed is a little low compared to what is obtainable with the stock ESC. More on that later.

My throttle curves ended up being 0-68-68-68-68 for normal and 72 flat for idle-up. To fly, I switch off throttle hold, push the throttle up to 1/2 stick and wait a few seconds for the headspead to stabilize. After that the head speed just doesn't change. If I want to fly in idle-up, I hit the switch after spool-up and go. The is some bogging on full throttle punch-outs; however, the acceleration out of hover is impressive. I did stall turns, loops and punch-outs the other day and it was solid. With the headspeed holding steady the heli is really smooth now.

There is one more thing I'd like to try, an 11T pinion. That would get the head speed up a little more. I'd like to have 2700 in normal and 3000 in idle up. I will report back on that when I get it done. I'll have to get a camera man and shoot some video too.