Specifications

YORK INTERNATIONAL 21
FORM 160.48-O1
COMPRESSOR SWITCH
(Refer to Fig. 15, page 18)
This rocker switch is used to locally operate the com-
pressor. It is used to start, run and stop the compressor.
Also, it resets the Control Center after a safety shut-
down.
To START* chiller compressor in “LOCAL” mode:
Move “COMPRESSOR” switch from “STOP/RESET”
to “START” position. Switch will spring-return to “RUN”
position.
*NOTE: The operator cannot start the compressor
(using this switch) when the Control Center
is in “REMOTE” mode.
To STOP compressor:
Move switch from “RUN” to “STOP/RESET” position.
To RESET Control Center:
Following a safety shutdown, the operator is required
to reset the Control Center prior to restarting the
system. Move switch from “RUN” to “STOP/RESET”
position.
DISPLAY MESSAGES
The following display 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-
programmed “XXX % FLA” current limit value. When
the motor current reaches 100% of this value, the
prerotation 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”
current 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 open-
ing further
(104%) (50% x FLA) = Vanes driven toward close
position
When 10 minutes have elapsed, access to
“PROGRAM” key will be automatically dis-
abled and the operator must return to step
No. 1 to gain access.
7. Press “PROGRAM” key.
8. This message is displayed:
PROGRAM MODE, SELECT SETPOINT
9. Press “MODE” key.
10. The mode that has been previously selected will be
displayed as follows:
- or - LOCAL MODE SELECTED
- or -
SERVICE MODE SELECTED
REMOTE MODE SELECTED
11. Press “ADVANCE DAY” key to scroll to desired
mode. Each time this key is pressed, a different
mode is displayed as above:
12. When the desired mode is displayed, press “EN-
TER” key.
13. This message is displayed:
PROGRAM MODE, SELECT SETPOINT
14. Press “ACCESS CODE key to exit “PROGRAM”
mode and terminate access to “PROGRAM” mode.
15. This message is displayed:
ACCESS TO PROGRAM MODE DISABLED