Moniteq CRYPTO-LOCK CC-8521AN, Инструкция по эксплуатации

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13
7.
THEORY OF OPERATION
A.
GENERAL
The CC-8521A
N
Crypto Lock consists
of two main units, the Keypad and
Control Unit.
B. KEYPAD
Refer to the Keypad Schematic Diagram
on moniteq.com.
The Keypad contains a
telephone-type key switch, an LED
indicator lamp and an annunciator push
button.
The Control Unit contains the Logic
Board, the
Power Supply
Board and the
Power Transformer.
C. LOGIC BOARD
The Logic Board processes key strokes
from the Keypad to determine if the lock
relay should be energized based on the
PIN code set on the DIGIT DIP switches.
The Logic Board also accepts the input
from the Annunciator Button on the
Keypad for routing to the
Power Supply
Board, and generates a signal to illuminate
the green LED on the Keypad when a valid
PIN code has been entered.
Chip U4 is a divide-by-8 counter that
decodes successive inputs from the
Keypad. The decoded outputs of U4 are
coupled through the respective DIGIT DIP
switches (S1,2,3,5 and 7) to U4's Clock
Enable input. If a valid first digit is
pressed the high signal on the "0" decoded
output (U4, pin 2) is coupled through the
valid number's key switch through T1 pin
11, U2C and Q4 to the clock enable input
of U4, advancing the counter one count
and causing the "1" decoded output (U4,
pin 1) to go high. If the second digit from
the keypad is also valid the process repeats,
again advancing the counter.
When the last
correct digit is entered a high signal is
coupled to both inputs of gate U2:B that then
triggers the
Open Timer, U1:B. The output
of U1:B then remains high for a time period
set by the DURATION potentiometer R19.
This output is coupled to Relay Driver Q5
which grounds the signal connected to the
door control relay on the Power Supply
Board.
If an incorrect digit is entered on the Keypad
the divide-by-8 counter U3 is advanced one
count, thereby triggering Penalty Timer
U1:A that resets Open Timer U1:B for a
time period set by
PENALTY potentiometer
R8.
D. POWER SUPPLY BOARD
The Power Supply Board contains the
power
supplies for powering both the internal
circuits and driving the external locking
device. It also manages the standby batteries
and routes signals from the external release
button to the Logic Board and from the
Logic Board to the external annunciator.
The 24Vac output from the secondary of the
power transformer is applied to bridge
rectifier D2 and filter components C4, R3
and C2 and regulator Q2 to generate
27.3Vdc. When OUTPUT SOURCE switch
S2 is set to INT 24V and OUTPUT MODE
switch S1 is closed, this voltage is coupled
through door control relay K1 to either pin
10 or pin 11 of T2 depending on the status