Bryant 551B Series, Инструкция по установке, запуску и обслуживанию

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c. Connect T and T1 to the 24 V power supply.
d. After installation is complete, calculate the mini-
mum airflow across the economizer. To calculate the
minimum airflow, the following data is needed: total
cfm (cfm
3
), temperature of the total cfm (T
3
), tem-
perature of the return air (T
2
), and temperature of
the entering outside air (T
1
). Cfm
1
is the outside air
cfm, which will be the minimum airflow.
T
1
(cfm
1
) + T
2
(cfm
2
)
= T
3
cfm
3
cfm
2
= (cfm
3
– cfm
1
)
Therefore:
T
1
(cfm
1
) + T
2
(cfm
3
– cfm
1
)
= T
3
cfm
3
Use this equation to determine cfm
1
, which is the mini-
mum airflow across the economizer.
(T
3
– T
2
) cfm
3
cfm
1
=
(T
1
– T
2
)
If cfm
1
does not match the desired minimum air-
flow from Step 1, re-adjust the minimum position set-
ting screw.
MINIMUM POSITION
OPEN
3
1
T
P
P1
T1
4
2
5
S
S
O
D
C
TR
B
REV
. B
198818A
%
H U
M
I D
I T
Y
90
70
60
30
10
D
C
B
A
60
65
70
75
55
50
85
80
DAMPER
DAMPER
CLOSED
OPEN OUTDOOR TEMP
.
°
F
REV.
97-3672
CW–SETPOINTS–CCW
CONT
A
CTS SHO
WN IN HIGH ENTHALPY
RUSH A
T
24V
AC
3 mA
MIN.
A
T
1
1
VDC
CONT
ACT RA
TINGS: 1.5A
RUN, 3.5A
IN
OR UNPOWERED ST
A
T
E
1
2
3
TR
TR1
24V
AC
ENTHALPY
CONTROL
Fig. 18 — Outdoor-Air Thermostat/
Enthalpy Control Installation
LEGEND
OAT — Outdoor-Air Thermostat
NOTE: See unit wiring diagram for more details.
Fig. 19 — Wiring Connections for Outdoor-Air Thermostat
Fig. 20 — Varislide™ Economizer Barometric Relief
Damper Characteristics
—15—