Daikin Magnitude WME Series, Инструкция по установке, эксплуатации и обслуживанию

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IOM 1266-2 • MAGNITUDE
®
MODEL WME CHILLERS 40 www.DaikinApplied.com
o
peraTIon
Figure 50: Strategy (III) VALVE STAGE -
Valve Opening vs. Temperature
As shown in Figure 50 , the default minimum and maximum
valve opening positions are 10% and 90%, respectively. These
minimum and maximum positions are adjustable anywhere
between 0% and 100%. Additional fan stages on when the
valve opening position reaches the maximum value that was
set.
Strategy (IV) NONE
:
This control strategy is tower fan
staging only. This is not a recommended strategy. In this
mode, the tower fan staging (up to two stages) is controlled
by either the condenser Entering Water Temperature (EWT)
or LIFT pressure (difference between the condenser and
evaporator pressure). Tower bypass or fan speed are not
controlled. See Figure 51 and Figure 52 .
To set up in HMI:
The following settings are used for the Tower Fan Staging Only
mode:
1. Select TEMP if Cooling Tower Control is based on
condenser EWT or LIFT if based on compressor lift
expressed in pressure.
2. Set Tower Valve/VFD as NONE for no bypass valve or
fan VFD control.
3. Set Cooling Tower Stages as one to three fan
outputs depending on the number of fan stages to
be used. More than one fan can be used per stage
through the use of relays.
4. Select Fan Stage Up Time from 1 to 60 minutes. The
default value of 2 minutes is a good starting point. The
value may need to be adjusted later depending on
actual system operation.
5. Select Fan Stage Down Time from 1 to 60 minutes.
The default value of 5 minutes is a good starting point.
The value may need to be adjusted later depending
on actual system operation.
If TEMP is selected for Cooling Tower Control, use:
a. Set Stage Differential in degrees F, default is 3°F.
b. Set the Stage Fan On temperatures consistent
with the temperature range over which the
condenser EWT is desired to operate. The
default values of 70°F, 75°F, and 80°F are a good
place to start in climates with moderate wet bulb
temperatures. The number of Stage Fan On
setpoints used must be the same as the number
of Cooling Tower Stages.
If LIFT is selected for Cooling Tower Control, use
a. Set Stage Differential in psi, default is 6.0 psi.
b. Set the Stage Fan On pressures starting with
default setpoints. The number of Stage Fan On
setpoints used must be the same as the number
of Cooling Tower Stages.
Figure 51: Strategy (IV) - NONE
Figure 52: Strategy (IV) NONE - Temp vs. Fan Stages
0
20
40
60
80
100
65 70 75 80 85 90
Valv
e O
pe
nin
g (
%
)
Temperature (°F)
2 Fan Stages 1 Fan Stage
Condenser
Cooling Tower
Fan Staging
(Up to 2 fans)
Tower
Control
Panel
MicroTech
®
Controller
65
70
75
80
85
90
95
0 1 2 3 4
Tem
per
at
ur
e (
°F
)
Fan Stages