Schulze 32.80 KA Speed Controller
My current choice for speed controllers are the Schulze brand which is built in Germany. Once again these controllers are an evolution in design from what was originally available transformed into a controller that is specifically targeted to F3A.
I had used the 32.55K controller (the K stands for cooling fins) in the 2005 season which I coupled to both the Xtra 25-13 and Xtra 30-10 motors over the season. This controller worked perfectly and was very light and simple to use. However downline speeds on the outrunners were uncontrollable and always resulted in picking up a good head of speed at the bottom. It was not until I spoke with Bernd Berschorner in France that I learned he had Schulze apply the car braking software to one of his controllers to help control the downlines. After the contest I persuaded Bernd to trade me controllers so that I could try out this braking as soon as I got home.
When I returned from France I mounted the controller and set it up according to what Bernd told me. It took a little work to get it just right but what a difference it made. Now we were able to fully control downline speed in the air and on demand, something no glow motor could do. I realized the need to have this in all controllers for pattern use and contacted the Canadian distributor (at the time I was not sponsored by and had no contact directly with Schulze) to attempt to have Schulze produce versions of the 32.55 and 32.80 with the brake feature as "F3A" controllers. Hence the 32.55KA and 32.80KA (A for aerobatic) controllers were born! Included with the changes was a boost in current handling from larger heat sinks on the 32.55. Now the 32.55KA can handle 62A-80A (vs. 55A-73A), and the 32.80KA is a 95A-115A rated controller.
I have had many questions on how to setup the brake on these controllers, so I will provide explanation here. Schulze has a link on their site that also provides some basic information here.
First thing, unlike other controllers on the market there is no need for a programmer, a laptop, or any other expensive pain in the butt device to program a Schulze, I really like simple devices that work and dont need 100 software updates before they work. 6 simple DIL switches on the controller do everything, for a Plettenberg outrunner motor using the aerobatic brake the switches are as follows:
1. ON
2. OFF
3. OFF
4. OFF
5. OFF
6. OFFWith OFF being towards the motor bullet connectors.
Now that was simple, so that has the brake activated, timing set to hard and the switching freq. at 9kHz. To finish setting the brake is all done in the transmitter. Since the brake is activated based on the pulse width of the signal being sent from the Rx to the ESC setting the brake is as simple as setting up ATV's and throttle curves on your transmitter. Also it is then adjustable via your idle trim, or simply by moving the throttle stick a bit.
My settings on a Futaba 9 ZWC2 for this controller are as follows,
ATV - 120% Rate A, 110-120% Rate B (120 is full throttle I have found).
Throttle Trim setting (TRM menu) - 50% below mid point, reads +50 on my Tx.
Make sure you activate your throttle curve, the point values are as follows.
1 - 0
2 - 38
3 - 50
4 - 55
5 - 59
6 - 64
7 - 69
8 - 73
9 - 78
10 - 82
11 - 88
12 - 93
13 - 100
D button sets the Low which is set to 80%, the dial is set to a value of +75% (that is the value in the brackets)....corresponds to about 1.5 to the right side of zero on the dial. The dial is how I affect the brake strength. Activate a dial by going to VOL, then H for left dial. Set the dial value to negative. That will give less brake when turning clockwise and vice versa.Hopefully that helps with the setup of the controller, as always if you are using other Tx's your milage will likely vary a bit but this should send you down the right path.
Another setup that I want to try to make the throttle curve more linear is to adjust the sub-trim value such that the center point is offset to the low side a bit, hopefully that will allow a straighter curve and save some setup time. If you give this a go and it works out great let me know :)