Carrier APOLLO CONTROL 50HJQ004-016, Данные о продукции

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190
CONTROL
CURVE
A
B
C
D
CONTROL POINT
APPROX. deg. F (deg. C)
AT 50% RH
73 (23)
70 (21)
67 (19)
63 (17)
12
1
4
16
18
20
22
24
26
28
30
32
3
4
36
38
40
42
44
46
9
0
1
0
0
80
70
6
0
50
40
30
20
10
ENTHALPY BTU PER POUND DRY AIR
85
(29)
90
(32)
95
(35)
100
(38)
105
(41)
110
(43)
35
(2)
35
(2)
40
(4)
40
(4)
105
(41)
110
(43)
45
(7)
45
(7)
50
(10)
50
(10)
55
(13)
55
(13)
60
(16)
60
(16)
65
(18)
65
(18)
70
(21)
70
(21)
75
(24)
75
(24)
80
(27)
80
(27)
85
(29)
90
(32)
95
(35)
100
(38)
A
A
B
B
C
C
D
D
RELATIVE HUMIDITY (%)
HIGH LIMIT
CURVE
APPROXIMATE DRY BULB TEMPERATURE--degrees F (degrees C)
C06037
ECONOMI$ER CHANGEOVER CURVES
Outside air enthalpy — EconoMi$er IV will be enabled based on
the outside air enthalpy curves as shown in the EconoMi$er IV
Changeover diagram below. The A, B, C, and D curves shown
have been in use for many years and have been included as part
of the latest ASHRAE 90.1 energy efficiency code. The curves
are designed to take into consideration both outdoor temperature
and humidity. These curves are used to set up the EconoMi$er IV
controller to use the EconoMi$er IV for free cooling when the
conditions to the left of the curve exist. When the conditions are
to the right of the curve, then outdoor air cooling will not be used
and the outdoor air damper position will be set at the minimum
position.
Deciding which curve is used is a function of the outdoor climate
and the type of economizer utilized. Since EconoMi$er IV is a
fully integrated economizer, the range where outdoor air can be
utilized for free cooling is expanded and the A and B curves may
be used. The control point table in the EconoMi$er IV
Changeover diagram below provides assistance for whether the A
and B curves will be suitable. In general terms, a hot and humid
climate may be a reason not to use the A curve, while a cooler
climate might be more applicable for using the A or B curve.
The EconoMi$er IV has expanded outdoor air capability. For a
changeover economizer which cannot utilize simultaneous
economizer and compression, both A and B curves would
potentially be undesirable since the temperature and humidity
levels are too high without compression assistance to provide
effective cooling. Therefore, most changeover economizers utilize
the D curve.
Differential enthalpy — The EconoMi$er IV will be enabled
based on the comparison of the enthalpy of the return air and
outside air. When the outside air enthalpy is lower than he return
side, the unit will be in economizer mode.
Using the EconoMi$er IV controller for implementing different
control changeover strategies requires the use of different
combinations of dry bulb and humidity sensors as outlined in the
EconoMi$er IV Sensor Usage table.
50
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