67
Using the following settings:
•
EP.MS
=20 (economizer commanded to 20% when
SFAN_VFD=
SP.MN
)
•
EP.XS
=5 (economizer commanded to 5% when
SFAN_VFD=
SP.MX
)
•
SP.MN
=20 (minimum SFAN_VFD speed)
•
SP.MX
=100 (maximum SFAN_VFD speed)
The economizer position would be command based on the
supply fan speed by interpolation between the (20,20) and
(100,5) coordinates: The results are shown in Fig. 15. The
comparison between the Dual Setpoint and Fixed Minimum
configurations is shown in the following example as in Fig. 16.
SETTING UP THE SYSTEM — The IAQ configuration op-
tions are under the Local Display Mode
Configuration
IAQ
.
See Table 69.
Economizer Min Position (
Configuration
IAQ
DCV.C
EC.MN
) — This is the fully occupied minimum economiz-
er position.
IAQ Demand Vent Min Pos. (
Configuration
IAQ
DCV.C
IAQ.M
) — This configuration will be used to set the mini-
mum damper position in the occupied period when there is no
IAQ demand.
IAQ Analog Sensor Config (
Configuration
IAQ
AQ.CF
IQ.A.C
) — This is used to configure the type of
IAQ position control. It has the following options:
•
IQ.A.C
= 0 (No analog input). If there is no other mini-
mum position control, the economizer minimum position
will be
Configuration
IAQ
DCV.C
EC.MN
and
there will be no IAQ control.
•
IQ.A.C
= 1 (IAQ analog input). An indoor air (space or
return air) CO
2
sensor is installed. If an outdoor air CO
2
sensor is also installed, or OAQ is broadcast on the CCN,
or if a default OAQ value is used, then the unit can per-
form IAQ control.
•
IQ.A.C
= 2 (IAQ analog input with minimum position
override) — If the differential between IAQ and OAQ
is above
Configuration
IAQ
AQ.SP
DAQ.H
, the
economizer minimum position will be the IAQ override
position (
Configuration
IAQ
AQ.SP
IQ.O.P
).
•
IQ.A.C
= 3 (4 to 20 mA minimum position) — With a 4
to 20 mA signal connected to TB5-6 and 7, the econo-
mizer minimum position will be scaled linearly from 0%
(4 mA) to
EC.MX
(20 mA).
•
IQ.A.C
= 4 (10K potentiometer minimum position) —
With a 10K linear potentiometer connected to TB5-6 and 7,
the economizer minimum position will be scaled linearly
from 0% (0 ohms) to
EC.MX
(10,000 ohms).
IAQ Analog Fan Config (
Configuration
IAQ
AQ.CF
IQ.A.F
) — This configuration is used to configure the control
of the indoor fan. If this option is used then the IAQ sensor
must be in the space and not in the return duct. It has the fol-
lowing configurations:
•
IQ.A.F
= 0 (No Fan Start) — IAQ demand will never
override normal indoor fan operation during occupied or
unoccupied period and turn it on.
•
IQ.A.F
= 1 (Fan On If Occupied) — IAQ demand will
override normal indoor fan operation and turn it on (if
off) only during the occupied period (CV operation with
automatic fan).
•
IQ.A.F
= 2 (Fan On Occupied/Unoccupied) — IAQ
demand will always override normal indoor fan operation
and turn it on (if off) during both the occupied and unoccu-
pied period. For
IQ.A.F
= 1 or 2, the fan will be turned on as
described above when DAQ is above the DAQ Fan On Set-
point (
Configuration
IAQ
AQ.SP
D.F.ON
). The fan
will be turned off when DAQ is below the DAQ Fan Off
Setpoint (
Configuration
IAQ
AQ.SP
D.F.OF
). The
control can also be set up to respond to a discrete IAQ input.
The discrete input is connected to TB5-6 and 7.
ECONOPOS %
25
20
15
10
5
0
15
25
35
45
55
65
75
85
95
105
SFAN_VFD %
Fig. 15 — Example of Economizer Position of Dual Setpoint Configuration
Содержание Carrier Weathermaker 48A2
Страница 105: ...105 Fig 20 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units...
Страница 106: ...106 Fig 21 Typical Auxiliary Control Box Wiring Schematic...
Страница 107: ...107 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown a48 8357...
Страница 108: ...108 TO NEXT PAGE Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown A48 7296...
Страница 109: ...109 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont A48 8358...
Страница 110: ...110 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown a50 8228...
Страница 111: ...111 Fig 25 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown...
Страница 112: ...112 Fig 26 Typical Low Ambient Controls Option Wiring...
Страница 113: ...113 Fig 27 Typical Small Chassis Component Location Size 020 035 Units...
Страница 114: ...114 Fig 28 Typical Large Chassis Component Locations Size 040 060 Units...
Страница 118: ...118 Fig 30 Economizer Control Board ECB1 and VAV Control Board ECB2 A48 7706...
Страница 142: ...142 A48 3733 Fig 56 Main Burner Removal...
Страница 176: ...176 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716...