references
SINGLE-EFFECT HOT WATER-FIRED ABSORPTION CHILLERS 16LJ/16LJ-A
Features and advantages
Expert self-diagnosis function
The expert function is provided to monitor operating conditions, predict chiller information and maintain stable operation.
Control system
The Carrier control system surpasses other proportional only control systems available today. The digital PID (proportional plus integral plus derivative) control maximises unit performance by maintaining a ±0.5 K variance in leaving chilled-water temperature from the setpoint. Proportional controls can typically only maintain a ±1 K variance from the setpoint. The controller’s innovative design also incorporates the ability to start and stop the system chilled/hot and cooling water pumps. During shutdown these pumps are sequenced to ensure a complete dilution cycle The leaving chilled-water temperature is measured every five seconds and steam input is changed according to the gradient of the leaving chilled-water temperature curve. System temperatures, setpoints, and operational records are displayed along with indicator lights for the chiller and pumps. The Carrier control system offers its users selfdiagnostics by constantly monitoring the chiller status and will automatically shut the chiller down if a fault occurs. The cause of shutdown will be retained in the memory and can be displayed for immediate operator review. The controller’s memory will also retain and display the cause of the last three system fault conditions. This method of retaining fault conditions is extremely useful for maintaining an accurate record of unit performance and fault history.
Predictive maintenance information Graph 1 - Fouling of heat transfer tubes in cooling water system
8
Fouling factor
Maintenance line Maintenance zone
6 4 2
Notice line
Normal line
0
0
20
40
60
80
100
Cooling load factor (%)
8
Abnormal stop zone
Display and control board Figure 2 - Indication lights
8
7
Concentrated indicator
6 5 4 3 2 1 0 0
Maintenance zone at cooling water 27°C Maintenance zone at cooling water 31°C
Normal line at cooling water 31°C
1 2
Normal line at cooling water 27°C
20
40
60
Cooling load factor (%)
80
100
7 8 9 4 10
Graph 3 - Vacuum condition monitoring
1.0
Pressure increase indicator at storage tank Maintenance zone
5
0.6
Notice zone
3 Legend 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. GL*. 43P*. 43ES*. Name Operation indication light Stop indication light Alarm indication light Remote/local select button with LED Operation select button with LED Data display Stand-by indication light Dilution indication light Safety circuit indication light Power indication light Purge indication light Purge pump on-off switch Emergency stop switch LED colour Green Orange Red Green Green 7 segment LED (red) Green Green Green orange
Normal zone
0 0 20 60
Storage ratio (%)
Legend 1. 2. 3. 4. 5. Storage tank Diluted solution Purge nozzle Pd cell Pressure sensor
*On the control panel door, see p.16
C
A
R
R
I
E
R
2
0
1
6
/
2
0
1
7
309
CONTROLS
80
100
AIR TREATMENT
HEATING HEATING
Graph 2 - Tend of absorbent concentration
COOLING
