McQuay WSC Operating Manual page 30

Cooling TOWER Fan Settings
Figure 18, Cooling TOWER Fan Setpoint Screen (See page 31 for complete explanation.)
Table 16, Tower Fan Settings
Description
Stage #4 On (Lift)
Stage #3 On (Lift)
Stage #2 On (Lift)
Stage #1 On (Lift)
Stage #4 On (Temp)
Stage #3 On (Temp)
Stage #2 On (Temp)
Stage #1 On (Temp)
Stage Differential (Lift)
Stage Differential
(Temp)
Stage Down Time
Stage Up Time
Tower Stages
Valve/VFD Control
Tower Control
30
No. Default Range
15 65 psi 10 to 130 psi
14 55 psi 10 to 130 psi
13 45 psi 10 to 130 psi
12 35 psi 10 to 130 psi
11 85 °F 40 to 120 °F
10 80 °F 40 to 120 °F
9
75 °F 40 to 120 °F
8
70 °F 40 to 120 °F
7 6.0 psi 1.0 to 20.0 psi
6
3.0 °F 1.0 to 10.0 °F
5 5 min 1 to 60 min
4 2 min 1 to 60 min
3 2 1 to 4
None, Valve
Setpoint, Valve
2 None Stage, VFD
Stage, Valve
SP/VFD Stage
None,
1 None Temperature,
Lift
Pass-
Comments
word
M Lift pressure for fan stage #4 on
M Lift pressure for fan stage #3 on
M Lift pressure for fan stage #2 on
M Lift pressure for fan stage #1 on
M Temperature for fan stage #4 on
M Temperature for fan stage #3 on
M Temperature for fan stage #2 on
M Temperature for fan stage #1 on
M Fan staging deadband with Setpoint # 1=Lift
M Fan staging deadband with Setpoint #1=Temp
Time delay between stage up/down event and
M
next stage down
Time delay between stage up/down event and
M
next stage up
M Number of fan stages used
None: No tower valve or VFD
Valve Setpoint: Valve controls to VALVE SP3(4)
& 5(6)
M Valve Stage: Valve control setpoint changes to
fan stage setpoint
st
VFD Stage: 1 fan is VFD controlled, no valve
Valve Setpoint/VFD Stage: Both valve and VFD
None: No tower fan control
M Temperature: Fan and valve controlled by EWT
Lift: Fan and valve controlled by lift pressure
OM Centrif Micro ΙΙ-5