Dual Centrifugal Chillers Control Application - Honeywell AUTOMATIC CONTROL Engineering Manual

DUAL CENTRIFUGAL CHILLERS CONTROL APPLICATION

FUNCTIONAL DESCRIPTION
MORNING LEAD
CHILLER SELECTOR
78
1 = CHILLER 1 LEADS
2 = CHILLER 2 LEADS
3 = ALTERNATES
12
TOWER
19
CONTROL
4 ON
13
91
ENABLED
4
DISABLED
OFF
14
85
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.
CHILLER, BOILER, AND DISTRIBUTION SYSTEM CONTROL APPLICATIONS
CHILLED WATER SETPOINT
42
1
MINIMUM
9
CHILLER 1
1
3 15
ON
AUTO
BY REMOTE OPERATING STATUS
CONTROLS MODE
OFF
AUTO
CHILLER 2
Fig. 14. Dual Centrifugal Chiller Control Graphic.
6
46
50
MAXIMUM
CURRENT
7
CHILLER
CONTROL
SETPOINTS
SEQUENCES
42
5
17
11
78 NORMAL
100
PERCENT LOAD ALARM
8
STATUS
MAX CURRENT
100
00 NORMAL
55
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.
309 ENGINEERING MANUAL OF AUTOMATIC CONTROL
18 20
FLOW &
PRESSURE
CONTROL
CONTROL
PROGRAM
42.1
2
AUTO
55.0
11
2
AUTO
M10497
10