FORM 160.52-O1
23
YORK INTERNATIONAL
(See Fig. 13, page 19.)
This rocker switch is used to locally operate the com-
pressor. It is used to start, run and stop the compres-
sor. Also, it resets the Control Center after a safety
shutdown.
To
START*
chiller compressor in
LOCAL
mode:
Move
COMPRESSOR
switch from
STOP/RESET
to
START
position. Switch will spring-return to
RUN
po-
sition.
To
STOP
compressor:
Move switch from
RUN
to
STOP/RESET
position.
COMPRESSOR SWITCH
To
RESET
Control Center:
Following a safety shutdown, the operator is required
to reset the Control Center prior to restarting the sys-
tem. Move switch from
RUN
to
STOP/RESET
position.
*NOTE: The operator cannot start the compressor (us-
ing this switch) when the Control Center is in
REMOTE
mode.
DISPLAY MESSAGES
The following displayed messages will be automatically
displayed unless the operator is requesting additional
information via the keypad.
SYSTEM RUN - CURRENT LIMIT IN EFFECT
Displayed when the chiller is running, and the motor
current is equal-to or greater-than the operator-pro-
grammed XXX % FLA current limit value. When the
motor current reaches 100% of this value, the pre-ro-
tation vanes are not permitted to open further. If the
current continues to rise to 104% of this value, the vanes
will be driven closed not fully closed; only far enough
to allow the current to decrease to a value less than
104% of the operator-programmed XXX % FLA cur-
rent limit.
For example:
With the operator-programmed % CURRENT LIMIT
set at 50% and the FLA of the chiller equal to 200A, the
current limit circuit would perform as follows:
(100%) (50% x FLA) = Vanes inhibited from opening further.
(104%) (50% x FLA) = Vanes driven toward close position.
Therefore:
(100%) (50% x 200) = 100A = Vanes stop opening
(104%) (50% x 200) = 104A = Vanes driven toward close position.
SYSTEM RUN AUTO VANES
Displayed when the chiller is running, the MicroCom-
puter Control Center is in
SERVICE
mode, and the
vanes are operating in
AUTO
mode.
SYSTEM RUN VANES OPENING
Displayed when the chiller is running, the MicroCom-
puter Control Center is in
SERVICE
mode with:
The vanes operating in
AUTO
mode and opening
to maintain the leaving chilled water temperature
setpoint.
or
The operator has pressed the vanes
OPEN
key on
the keypad.
SYSTEM RUN VANES CLOSING
Displayed when the chiller is running, the MicroCom-
puter Control Center is in
SERVICE
mode with:
The vanes operating in
AUTO
mode and closing to
maintain the leaving chilled water temperature set-
point.
or
The operator has pressed the vanes
CLOSE
key
on the keypad.
SYSTEM RUN - VANES HOLDING
Displayed when the chiller is running, the MicroCom-
puter Control Center is in
SERVICE
mode, and the
operator has pressed the vanes
HOLD
key.
