Johnson Controls 40 25 TON, Установка, эксплуатация и обслуживание

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131
JOHNSON CONTROLS
5276178-JIM-C-0118
5
Hardwired SAT Reset
When the “SAT RESET METHOD” is set to
“HARDWIRED”
, the Unit Controller monitors the
“SUPPLY AIR TEMP RST”.
If the
“SUPPLY AIR
TEMP RST” is equal to 0.0, the “SUPPLY AIR TEMP
ACTIVE SP” is the “SAT HIGH SETPOINT”. If
the “SUPPLY AIR TEMP RST” is equal to 5.0, the
“ACTIVE SP”
is the
“SAT LOW SETPOINT”.
When
the
“SUPPLY AIR TEMP RST”
is between 0.00 and
5.00, the “SUPPLY AIR TEMP ACTIVE SP” is linearly
interpolated between the “SAT HIGH SETPOINT” and
the “SAT LOW SETPOINT” (see Figure 61).
This feature is only available as a communicated
command through a BAS system. To enable this feature
“SAT RESET BAS” must be set to USER ENABLE
through the SERVICE key of the User Interface.
Outside Air Based SAT Reset
When the “SAT RESET METHOD” is set to “OUTSIDE
AIR”
, the Unit Controller monitors the
“OUTSIDE AIR
TEMP”
and sets the
“SUPPLY AIR TEMP ACTIVE SP”
to a value between the “SAT HIGH SETPOINT” and
the “SAT LOW SETPOINT” . If the “OUTSIDE AIR
TEMP” is equal to or less than the “OAT SETPOINT
FOR HIGH SAT”
the
“SUPPLY AIR TEMP ACTIVE
SP”
is the
“SAT HIGH SETPOINT”
. If the
“OUTSIDE
AIR TEMP” is equal to or greater than the “OAT
SETPOINT FOR LOW SAT” the “ACTIVE SAT SP”
is the “SAT LOW SETPOINT” . When the “OUTSIDE
AIR TEMP”
is between the
“OAT SETPOINT FOR
HIGH SAT”
and the “
OAT SETPOINT FOR LOW
SAT” , the “SUPPLY AIR TEMP ACTIVE SP” is linearly
interpolated between the “SAT HIGH SETPOINT” and
the “SAT LOW SETPOINT” (see Figure 62).
FIGURE 66 - ACTIVE SAT SET POINT VS. SUPPLY AIR TEMP RST VOLTAGE
Outside Air Temp
(OAT)
Active SAT
Set Point
Increasing OAT
(Default = 65.0
°
F)
SAT HIGH SETPOINT
(Default = 55.0 °F)
SAT LOW SETPOINT
OAT SETPOINT
FOR HIGH SAT OAT SETPOINT
FOR LOW SAT
LD12588
FIGURE 67 - ACTIVE SAT SET POINT VS. OUTSIDE AIR TEMP
5 Volts
0 Volts
(Default = 65.0
°
F)
Supply Air Temp Rst
Voltage
(Volts DC)
Acti ve SAT
Set Point
SAT HIGH SETPOINT
(Default = 55.0 °F)
SAT LOW SETPOINT
LD12587
0 5