The schematic circult of the Pendulum Alarm is shown in Figure l.The circuit
has as its heart an SCR (Silicon Controlled Rectifier), which energizes the
relay when the sensor detects any movement.
A mechanical view of the circuit mounting, using a terminal strip as chassis,
is shown in Figure 2.
Relay coil voltage is chosen according to the power supply voltage. You can
use a mini DPDT 1A Mini Relay (Radio Shack 275'249) or, for heavy loads, a
10A mini SPDT relay (Radio Shack 275-248).These rlays are rated lo 12
VDC and drain only 38 mA (their coil resistance is about 320 ohms). As
equivalent types can be used, you should take care with terminal layout.
Reset can be made with a momentary-typ6 switch (Push-On) wired between
the SCR anode and catode, or by using the on-otf switch.
Positions of polarized components,uch as the SCR and diode, should be
::t::r":tairs are atso siven in Fisurc2. Norice that operation occurs when
the vertical (or horizontal) bare wire touches the ring during any movement.
Parts of Pendulum
SCR -TlC106 or equivalent Silicon Gontrolled Rectifier
D1 - 1N914 or equivalent general-purpose silicon diode
K1 - 12V relay (see text)
S1 - SPST slide or toggle switch
Rl - 22,OOO ohm, 114W,5% resistor
R2 - 10,000 ohm, 114W,5% resistor
X1 - Pendulum sensor (see text)
No comments:
Post a Comment