Carrier 17/19EX PIC System Functions

PIC System Functions
Note: Throughout this manual , words printed in capita l letters and italics are val ues that may be
viewed on the LID. See Tab le 2 f or examples of LID screen s. Point names are list ed in
the Description column. An overview of LID operation and menus is given in Figure 14,
Figure 15, Figure 16, Figure 17, Figure 18, Figure 19, and Figure 20 .
Capacity Control
The PIC controls the mach ine capacity by modulatin g the inlet guide vanes in r es po nse to
chilled water tempera ture changes away from the
CONTROL PO INT
. The
CONTROL POINT
may be changed by a CCN networ k de vice, or is determined by the PIC adding any active
chilled water reset to the ch illed water
SET POINT
. The PIC uses the
PROPORTIONAL INC
(Increase) BAND, PROPORTIONAL DEC (Decrease) BAND
, and the
PROPORTIONAL ECW
(Entering Chilled Wa ter) GAIN
to determine how fast or slow to respond.
CONTROL POINT
may be viewed/o verridden on th e Status table, Status01 sel ection.
Entering Chilled Water Control
If this option is enable d, the PIC uses
ENTERING CHILLED WAT ER
temperature to
modulate the vanes inst ead of
LEAVING CHILLED WATER
temperature.
ENTERING CHILLED
WATER
control option may be vie wed/modified on the Equ ipment Configuratio n table, Config
table.