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YORK INTERNATIONAL
66
Sequence of Operation
FORM 100.50-NOM1 (604)
• The measured air
ß
ow above is entered into the Pri-
mary Unit Controller through the parameter “
AMS
#X Balancer Calculated Airfl ow at Balance”.
X can
be either 1 or 2. Use 1 for the Minimum and Full
ß
ow measurement option. This parameter is found
under the SERVICE key of the OptiLogic Panel.
• During the same time-period of the measurements
by the air balancer, record the Primary Unit Control-
ler calculated air
ß
ow for AMS 1 or 2. This informa-
tion can be found under the parameter “
Outside Air
Damper Flow # X”
under the OPERATION DATA
key of the OptiLogic Panel.
• The Primary Unit Controller calculated air
ß
ow
above is entered into the Primary Unit Controller
through the parameter “
AMS #Xcontroller Mea-
sured Air Flow at Balance”
. This parameter is
found under the SERVICE key of the OptiLogic
panel.
Minimum Flow Measurement
If the Con
Þ
guration setting
"Airfl ow Measurement Con-
fi guration"
is set to 1 (minimum), then the unit will be
equipped with minimum
ß
ow-only measurement equip-
ment. This ar range ment consists of an AMS and damper
sized for 25% total unit
ß
ow and a separate economizer
damper sized for the remaining 75% (does not include
an AMS). The following
Þ
gure details this arrangement
and in di cates the three independently controlled damp-
ers re quired for this option. Damper #1 and #2 will be
ar ranged Normally Closed (0V = Closed, 10V = Open)
and Damper #3 will be arranged Normally Open (0V =
Open, 10V = Closed). See Figure 32.
Sequence of Operation
AREA AND K-FACTOR
When an Air Measuring Station is installed from the
factory, the following parameters should be set at the
factory prior to the shipment of the unit. The following
parameters are found under the CONFIGURATION key
of the OptiLogic control: “
AMS #1 Area”, “AMS #1 K-
Factor”, “AMS #2 Area”, “AMS #2 K-Factor”.
Table
18 lists
the values that should be entered for each of the
parameters based on the capacity of the unit.
OA Flow Sensor Auto-Zero
Each OA
ß
ow sensor will under go an auto-zero pro-
cess to minimize the effect of zero drift on the sensor
ac cu ra cy. Auto-zero will take place when:
• Occupancy state = unoccupied
• Supply Fan = OFF
• Outdoor Air Damper = closed
The controller will take three air
ß
ow measurements with
a 5 minute interval between each measurement. The
measurements will be used to calculate a correction to
the air
ß
ow measurement used for control.
Airfl ow Correction Using Balancer Data
The outdoor air
ß
ow function will allow the entry of
data to correct the air
ß
ow measurement based on mea-
sure ments taken by an air balancer. Computation of the
compensated OA
ß
ow adjusted by air balancer input is
done through the following steps and computation:
• The air balancer takes measurements and calculates
an air
ß
ow (CFM) for the AMS
AIR MEASURING
STATION OPTION
Open %
Full
Unit Size (Tons)
50, 55
60,65
70,75
80,85
90,95,
105
MINIMUM
25%
A1 (Flow area sq ft)
3.61
3.61
4.17
4.17
4.72
K1-1
0.751
0.751
0.770
0.770
0.775
FULL
100%
A1 (Flow area sq ft)
14.44
14.44
16.67
16.67
18.89
K1-1
0.705
0.705
0.666
0.666
0.673
TABLE 18 – AREA AND K FACTOR