Dual Centrifugal Chillers Control Application - Honeywell AUTOMATIC CONTROL SI Edition Engineering Manual

DUAL CENTRIFUGAL CHILLERS CONTROL APPLICATION

FUNCTIONAL DESCRIPTION
MORNING LEAD
CHILLER SELECTOR
1
26
1 = CHILLER 1 LEADS
2 = CHILLER 2 LEADS
3 = ALTERNATES
12
TOWER
19 CONTROL
ON
4
13
1
32.5
ENABLED
BY REMOTE
CONTROLS
4
DISABLED
OFF
14
29.5
Item No. Function
1 Indicates when chilled water is required by
fan system.
2 Chilled water pump ON-OFF-AUTO
function. In AUTO pump runs when system
needs chilled water.
3 Chiller ON-OFF-AUTO function (In ON and
AUTO chilled water flow required for chiller
to run).
4 Condenser pumps status. Pumps started by
chiller controls when chiller needed.
ENGINEERING MANUAL OF AUTOMATIC CONTROL
CHILLER, BOILER, AND DISTRIBUTION SYSTEM CONTROL APPLICATIONS
CHILLED WATER SETPOINT
5.5
MINIMUM
9
SEQUENCES
CHILLER 1
3 15
ON
AUTO
OPERATING STATUS
MODE
OFF
AUTO
CHILLER 2
Fig. 14. Dual Centrifugal Chiller Control Graphic.
6
8
10
MAXIMUM
CURRENT
7
CHILLER
CONTROL
SETPOINTS
5.5
5
11 17
78
100 NORMAL
8 PERCENT LOAD ALARM
STATUS
MAX CURRENT
100
00 NORMAL
13
5
5,6 Chiller leaving water temperature and setpoint.
7 Icon to select chilled water setpoint reset
dynamic sequence display (Fig. 15).
8 BMCS commandable load limiting functions.
9 Lead chiller selector function.
10-17 Operator information.
18 Control program coordinates chiller staging
and control.
19 Icon to select cooling tower control displays.
20 Icon to select chilled water flow and pressure
control displays.
307
18 20
FLOW &
PRESSURE
CONTROL
CONTROL
PROGRAM
2 5.6
AUTO
13
11
2
AUTO
M15255
10