Pixie-7P
™
By
Castle Creations
™
Programmable Sub Micro Digital Motor Control
Pixie-7P
™
User Guide
Page 2 of 5
Rev 6-dated 02/06/02
This document, Pixie-7P software, and Pixie-7P PCB layout are all Copyright
2001 by Patrick del Castillo and
Castle Creations™.
All Rights Reserved.
3.0
Flying with Your
Pixie-7P
:
Initialization sequence:
1. Connect the speed controller receiver connector to the proper channel on your receiver (usually channel 3)
2. Turn on your transmitter.
3. Connect the main power battery to the speed controller. The motor will emit a single beep.
4. The speed controller will remain disarmed (will not operate) until it sees more than 1 1/2 seconds of “OFF”
throttle. Move the throttle arm to the lowest position on your transmitter; wait at least 1 1/2 seconds. The
motor will emit two beeps when armed and the LED will flash slowly. Test the controller to make sure that
the throttle operates.
5. Go fly!
6. If the BEC cutoff occurs before you land, you may restart the motor and use low throttle if necessary by
moving the throttle stick all the way down (to the off position) and then throttling back up. BEC cutoff
will occur again if the voltage drops too low.
4.0
Using the Features of Your
Pixie-7P
Auto-calibrating Throttle Range
– The throttle range is auto-calibrated to the transmitter in use to insure
maximum throttle steps.
BEC
- The BEC power is supplied to the receiver and servos through the receiver connector wires. If you
wish to disable the BEC and use a separate receiver battery (required for more than eight cells), you must first
cut the red wire in the trio of receiver wires. Simply use a pair of wire cutters to remove a short section of the
red wire near the receiver connector, and be sure to insulate the cut wire with a bit of electrical tape. Or
remove the pin from the connector (pry the retaining tab up, remove the pin, and insulate the pin with
electrical tape.) Then you may safely use a battery with your receiver.
Fixed Throttle Range
– Fixed throttle range sets the throttle to 1.25 to 1.75 ms fixed.
Hard Cutoff
– Hard motor cutoff will occur when the input battery voltage drops below the programmed
voltage for more than one half second. Once motor cutoff has occurred, moving the throttle to the full off
position can rearm the controller. This will allow restart of the motor at low throttle after cutoff has occurred.
WARNING! Restarting of the motor may drain the battery to the point where the radio receiver will
stop operating, resulting in a loss of control of the model.
Losses of Transmitter Signal, or excessive radio noise
cutoff - Motor cutoff will also occur if the signal
from the transmitter is lost, or if the radio noise becomes excessive. After radio connection has been
reestablished, moving the throttle to the braking position (full off) can restart the motor.
Programming Mode
– The Pixie-7P is already programmed from the factory for: a) 4.7v cutoff, b) a hard
cutoff with reset and c) auto calibrating throttle end points. To change any or all of these settings follow the
programming instructions beginning in section 7.0.
Safe Power Up
- The Safe Power up feature is a “finger saver”, designed to prevent the motor from starting
accidentally on power up. To arm the controller, the transmitter stick must be held in the “OFF” position (all
the way down) for at least one and a half seconds. Until the controller is armed, it will not provide any power
to the motor, regardless of where the throttle stick on your transmitter is positioned. Before flying your
model, be sure to “blip” the throttle to ensure that the controller is armed.
Soft Cutoff
- Soft Cutoff reduces the throttle level to keep the voltage at or near the programmed cutoff
voltage level.
WARNING! Soft cutoff is not recommended because it is easy to accidentally run the batteries down
to a point where the receiver and servos stop responding or battery damage occurs.
5.0
Troubleshooting
Everything is hooked up correctly, the BEC (receiver and servos) works, but the throttle does not work.
The controller is not seeing the one and a half seconds of “dead space” (low throttle) and is not arming. The
motor should emit two “beeps” when it arms. Try moving your throttle stick all the way down, and moving
the trim all the way down. Wait for a couple of seconds and try the throttle again. If it still does not arm, you
may need to reverse the throttle control on your transmitter (see your radio documentation). You may also
check to make sure that your endpoint adjustments on your radio (if it has them) are set all the way open.
Every time I throttle all the way up, the controller “cuts off” after a few seconds, even with fresh
charged batteries.
The controller will automatically shut down the motor if the battery voltage falls below programmed cutoff
voltage for more than a half second. This prevents loss of control caused by low voltage at the receiver. If the
cutoff is kicking in with freshly charged batteries, it means that the voltage is dropping very quickly. This is
usually an indication of a motor that is drawing too much current for the batteries to handle. Try using a
smaller prop on the motor, or using batteries with a higher rating (for example, if you are using 600 AE cells,
you might try going to 800 AR cells.)
It is also possible that the microprocessor on the Pixie-7P is being overwhelmed by noise from the motor. This
can occur if the motor has no capacitors installed. In most cases the Pixie-7P does not require capacitors to be
installed on the motor. However, some motors are extremely noisy electrically, and need to have capacitors
installed. If this is the case, add a capacitor across the motor terminals, or even better, add three capacitors:
one across the motor terminals, and one from each terminal to the motor case. Capacitors can be purchased
from Radio Shack. Be sure to get “ceramic disk” capacitors, in the range of .01uF and .1uf (.047uF being the
best choice.) Do not use electrolytic (can style) or tantalum capacitors with a high-rate control.
When everything is all connected and powered on the motor emits continuous “beep” sounds.
The unit is not receiving a signal from the receiver. Make sure the receiver connector is plugged in correctly
and plugged into the right channel of your receiver. Rule out the possibility of a faulty receiver.
Nothing seems to work, receiver and servos are dead, and the throttle is dead.
Check all connections to ensure that they are correct, and that the polarity (+/-) connections are correct.
Ensure that the battery is not connected to the motor side of the speed controller. If everything is correctly
connected, and the receiver and servos still do not work, contact the dealer where you purchased your Pixie-
7P or contact
Castle Creations
directly. (See info below)
