Functional Control
ESIE10-01
2–30
Part 2 – Functional Description
3
1
2
4
5
2.2.6
Evaporator Pump Control
For control of the evaporator pumps, three evaporator pump control states are possible:
■
Off – No pump on.
■
Start – Pump is on, water loop is being recirculated.
■
Run – Pump is on, water loop has been recirculated.
The control state is Off when all of the following are true:
■
Unit state is Off.
■
LWT is less than the Evap Freeze set point or LWT sensor fault is active.
■
EWT is less than the Evap Freeze set point or EWT sensor fault is active.
The control state is Start when any of the following are true:
■
The unit state is auto.
■
LWT is higher than the Evap Freeze set point plus 0.6°C and LWT sensor fault isn’t active.
■
EWT is higher than the Evap Freeze set point plus 0.6°C and EWT sensor fault isn’t active.
The control state should be Run when the flow switch input has been closed for a time greater than
the Evaporator Recirculate time.
Pump selection
The pump output used will be determined by the Evap Pump Control set point. This setting allows the
following configurations:
■
#1 only – Pump 1 will always be used.
■
#2 only – Pump 2 will always be used.
■
Auto – The primary pump is the one with the least run hours, the other is used as a backup.
■
#1 Primary – Pump 1 is used normally, with pump 2 as a backup.
■
#2 Primary – Pump 2 is used normally, with pump 1 as a backup.
■
Primary/Standby Pump Staging
The pump designated as primary will start first. If the evaporator state is start for a time greater
than the recirculate timeout timer and there is no flow, then the primary pump will shut off and the
standby pump will start. When the evaporator is in the run state, if flow is lost for more than half of
the flow proof set point value, the primary pump will shut off and the standby pump will start. Once
the standby pump is started, the flow loss alarm logic will apply if flow cannot be established in the
evaporator start state, or if flow is lost in the evaporator run state.
■
Auto Control
If auto pump control is selected, the primary/standby logic above is still used. When the evapora-
tor is not in the run state, the run hours of the pumps will be compared. The pump with the least
hours will be designated as the primary at this time.
Summary of Contents for EWAD620-C17C-SL
Page 2: ......
Page 8: ...ESIE10 01 1 2 Part 1 System Outline 3 1 1 5 ...
Page 111: ...ESIE10 01 General Outline Part 1 System Outline 1 105 3 1 4 5 1 36 1 Power Compressor 1 2 ...
Page 112: ...General Outline ESIE10 01 1 106 Part 1 System Outline 3 1 1 4 5 1 36 2 Power Compressor 3 ...
Page 113: ...ESIE10 01 General Outline Part 1 System Outline 1 107 3 1 4 5 1 36 3 Kit Pumps ...
Page 122: ...General Outline ESIE10 01 1 116 Part 1 System Outline 3 1 1 4 5 1 36 12 Digital Inputs Board ...
Page 123: ...ESIE10 01 General Outline Part 1 System Outline 1 117 3 1 4 5 1 36 13 Digital Outputs Board ...
Page 124: ...General Outline ESIE10 01 1 118 Part 1 System Outline 3 1 1 4 5 1 36 14 Digital Outputs Board ...
Page 131: ...ESIE10 01 General Outline Part 1 System Outline 1 125 3 1 4 5 1 36 21 EEXV Compressor 1 ...
Page 134: ...General Outline ESIE10 01 1 128 Part 1 System Outline 3 1 1 4 5 1 36 24 EEXV Compressor 2 ...
Page 137: ...ESIE10 01 General Outline Part 1 System Outline 1 131 3 1 4 5 1 36 27 EEXV Compressor 3 ...
Page 138: ...General Outline ESIE10 01 1 132 Part 1 System Outline 3 1 1 4 5 1 36 28 Pumps Control ...
Page 139: ...ESIE10 01 General Outline Part 1 System Outline 1 133 3 1 4 5 1 36 29 Terminals M1 M2 ...
Page 140: ...General Outline ESIE10 01 1 134 Part 1 System Outline 3 1 1 4 5 1 36 30 Terminals M3 ...
Page 141: ...ESIE10 01 General Outline Part 1 System Outline 1 135 3 1 4 5 1 36 31 Terminals M5 MQ ...
Page 148: ...General Outline ESIE10 01 1 142 Part 1 System Outline 3 1 1 4 5 ...
Page 150: ...ESIE10 01 2 2 Part 2 Functional Description 3 1 2 5 ...
Page 170: ...The Digital Controller ESIE10 01 2 22 Part 2 Functional Description 3 1 2 4 5 ...
Page 200: ...Functional Control ESIE10 01 2 52 Part 2 Functional Description 3 1 2 4 5 ...
Page 202: ...ESIE10 01 3 2 Part 3 Troubleshooting 3 1 3 5 ...
Page 254: ...Alarms and Events ESIE10 01 3 54 Part 3 Troubleshooting 3 1 3 4 5 ...
Page 266: ...Controller Inputs and Outputs ESIE10 01 3 66 Part 3 Troubleshooting 3 1 3 4 5 ...
Page 280: ...ESIE10 01 4 2 Part 4 Commissioning and Test Run 3 1 4 5 ...
Page 286: ...Pre Test Run Checks ESIE10 01 4 8 Part 4 Commissioning and Test Run 3 1 4 5 ...
Page 289: ...ESIE10 01 Running Data Part 4 Commissioning and Test Run 4 11 3 4 5 1 ...
Page 290: ...Running Data ESIE10 01 4 12 Part 4 Commissioning and Test Run 3 1 4 5 ...