Solarbotics K MSE-U, Руководство пользователя

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Solarengine Theory
The Miller Solarengine (MSE) is a simple, effective Type-1 (voltage triggered) solarengine with
configurable turn-on voltage and discharge time. The turn-on voltage is determined by the type
of 1381 selected, and the discharge time configured by the size of capacitor C1.
While the solarcell charges the capacitor, its status is monitored by the 1381. When a preset
voltage is reached, the 1381 turns on the PN2222 transistor, which pulls power through the
motor, making the motor turn. R1 is presently a zero ohm resistor - the same thing as a piece of
wire. You can change R1 to something else if you are planning on driving components other
than a motor, like a LED, or another electronic circuit. Raising R1 will make the circuit stay on
longer, but it won’t pass as much power.
The 1381 stays on as long as it thinks there is sufficient voltage between its trigger value and
(trigger voltage - 0.3V) i.e.: 2.7V down to 2.4V (for the 1381E). To extend how long it stays on, we
use capacitor C2 and a diode. C2 gets charged up through the diode at the same time as the
solarengine main storage capacitor C1, but discharges much slower through the 1381 voltage
trigger to the transistor. We use the discharge time of C1 through the 1381 to set how long the
circuit stays on.
Using a C1 of 6.8µF, we get a discharge time of approximately 2 seconds while powering the
motor out of a micro-cassette mechanism. If you want, you can put in a smaller C1 (1.0µF) to get
more frequent, high-power bursts, or a larger for longer bursts, but the default 6.8µF capacitor is
practically ideal for the components in this kit.
D1
+
1381
3
2 1
PN2222
Transistor
Motor
C2
C1
Miller Engine (MSE)
3
" Ø®µÆ¨ ІªØ∞∫ Ά Motor Time On: Time to Recharge: Result:
Larger C1 Storage Cap Same Same Longer initial charge-up, quick, high-energy bursts. This is because C2 sets how long it stays on for. Make C2
larger to increase how long it stays on for when increasing C1.
Larger Solarcell Same Quicker Quicker initial charge-up and recharge times.
Larger C2 Timer Cap Longer Longer The motors stays on longer, which pulls more power out of the capacitor. This takes longer to recharge, but gives
a longer motor pulse.
Smaller C2 Timer Cap Shorter Shorter This will result in quick, high-energy bursts, but won't spin the motor for as long.
Higher 1381 Trigger Same Longer The 1381 sets at what voltage the circuit activates. If it gets too high, it gets harder for the solarcell to charge the
circuit up to that point.