York YDAJ87KU6, Руководство пользователя

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FORM 150.75-NM2
33
YORK INTERNATIONAL
A +12V REG supply voltage from each Power Supply
Board is converted to +5 REG by a voltage regulator
located on the Microprocessor Board. This voltage is
used to operate integrated circuitry on the board.
Four system switches located on each Microprocessor
Board activate or de-activate the individual systems
(compressors.)
POWER SUPPLY BOARD
The on-board switching power supply converts 24VAC
from the 2T transformer to +12V REG which is sup-
plied to the Microprocessor Board, Relay Board, and
40 Character Display to operate integrated circuitry.
A rectifier and filtering circuit for each motor current cir-
cuit rectifies and filters these signals to variable DC.
These signals are then fed to the Microprocessor Board.
A Power Supply Board is present in both the Master
and Slave Panel.
RELAY OUTPUT BOARD
These boards convert 0-12VDC logic level outputs from
the Microprocessor Board to 120VAC levels used by
motor contactors, solenoid valves, etc. to control sys-
tem operation. The common side of all relays on the
Relay Output Board is converted to +12V REG.
The open collector outputs of the Microprocessor Board
energize the DC relays by pulling the other side of the
relay coil to ground. When not energized, both sides of
the relay coils will be at +12VDC potential.
Relay Output Boards are present in both the Master
and Slave Panel.
CURRENT TRANSFORMER (C.T.)
A C.T. on the 3
f
power wiring of each motor sends AC
signals proportional to motor current to Power Supply
Board which recitifies and filters the signal to variable
DC voltage (analog). This analog level is then fed to the
Microprocessor Board to allow it to monitor motor cur-
rent.
40 CHARACTER DISPLAY
The 40 Character Display (2 lines of 20 characters),
present only on the Master Panel, is a liquid crystal dis-
play used for displaying system parameters and opera-
tor messages. The display has a lighted background
for night viewing as well as a special feature which in-
tensifies the display for viewing in direct sunlight.
KEYPAD
A single operator keypad, present only on the Master
Panel, allows complete control of the system from a
central location. The keypad offers a multitude of com-
mands available to access displays, program setpoints,
and initiate system commands.
BATTERY BACK-UP
Each Microprocessor Board contains a Real Time Clock
integrated circuit chip with an internal battery back-up.
The purpose of this battery back-up is to assure any
programmed values (setpoints, clock, cut-outs, etc.) are
not lost during a power failure regardless of the time
involved in a power outage or shutdown period.
FIG. 22 – POWER PANEL
25998A
1 & 2 FUSE
SYS 2 FAN
CONTACTORS
SYS 2 FAN
OVERLOADS
SYS 2
POWER WIRING
CONNECTION
POINT
TB1
CONNECTIONS
FOR OPTIONAL
ALARM’S, EVAP
PUMP, AND L & 2
115VAC CONTROL
PANEL SUPPLY
(MASTER ONLY)
SYS 1 FAN
CONTACTORS
SYS 1 FAN
OVERLOADS
SYS 1
POWER WIRING
CONNECTION
POINT