Johnson Controls 050, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
75
SECTION 5 – SEQUENCE OF OPERATION
FORM 100.50-NOM6
ISSUE DATE: 8/07/2017
5
The Simplicity Control turns off compressor operation
as follows:
• The supply air temperature is 5.0° F or more be-
low the “VAV COOLING SUPPLY TEMP UP-
PER SAT SETPOINT” or “VAV COOLING SUP-
PLY AIR TEMP LOWER SETPOINT”.
• It has been more than 5-minutes since the last
compressor was turned ON.
• The compressors will be turned off in the reverse
order they were turned ON.
Cooling – Unoccupied Stand Alone
The Simplicity Control cannot operate unoccupied
cooling with this method of control.
Heating – Occupied Stand Alone
The following parameters must be programmed into
the Simplicity Control:
• “VAV OCCUPIED HEATING ENABLED” –
This must be turned ON using Parameter 26 un-
der the PROGRAM key on the Simplicity control
board or under the HEATING SETUP tab in the
Simplicity PC software package.
• “MORNING Warm up/ VAV RETURN AIR
TEMP SETPOINT” – using Parameter 29 under
the PROGRAM key on the Simplicity control
board or under the HEATING SETUP tab in the
Simplicity PC software package.
• “VAV OCCUPIED HEATING SETPOINT” – us-
ing Parameter 27 under the PROGRAM key on
the Simplicity control board or under the HEAT-
ING SETUP tab in the Simplicity PC software
package.
• “SPACE SENSOR FAULT OVERRIDE EN-
ABLED” must be turned ON – using Parameter 8
under the PROGRAM key on the Simplicity con-
trol board or under the SYSTEMS OPTIONS tab
in the Simplicity PC software package.
The unit will initiate Occupied Heating when the fol-
lowing criteria are met:
• The return air temperature is 2.0° F less than the
“VAV OCCUPIED HEATING SETPOINT”.
• The return air temperature is 0.1° F below the
“MORNING WARM UP / VAV RETURN AIR
TEMP SETPOINT”.
The “VAV OCCUPIED HEATING SETPOINT”
should always be set below the “MORNING WARM
UP RAT SETPOINT”.
The unit will terminate Occupied Heating when the re-
turn air temperature is equal to the “MORNING WARM
UP RAT SETPOINT”.
Heating – Unoccupied Stand Alone
The Simplicity Control cannot operate unoccupied
heating with this method of control.
COMPRESSOR STAGING
The Unit Controller performs compressor staging as
follows:
• On a call for the first stage of compressor opera -
tion the Unit Controller closes an output at C1,
terminal 1 of the P12 connector, and compressor
1A is energized.
• On a second stage call for compressor operation
the Unit Controller closes an output at C2, termi-
nal 5 of the P12 connector, and compressor 2A is
energized.
• On a third stage call for compressor operation the
Unit Controller closes an output at C3, terminal 3
of the P12 connector, and compressor 1B is ener-
gized.
• On a fourth stage call for compressor operation
the Unit Controller closes an output at C4, termi-
nal 7 of the P12 connector, and compressor 2B is
energized.
CONDENSER FAN OPERATION
A call for the first stage of compressor operation will
close an output at CF1, terminal 1 of the P13 connec-
tor. The 24VAC output energizes the 6M contactor and
turns on condenser fan 1. This 24VAC output is also sent
to pressure switch PS3 and PS4. Pressure switch PS3 is
located on the system 1 discharge line and PS4 is located
on the system 2 discharge line. If the System 1 discharge
pressure rises above 360 psig the PS3 pressure switch
will close and energize the 7M contactor and turn on
condenser fan 2. If the System 2 discharge pressure rises
above 360 psig the PS4 pressure switch will close and
energize the 9M contactor and turn on condenser fan 4.
A call for the third stage of compressor operation will
close an output at CF2, terminal 2 of the P13 connec-
tor. The 24VAC output will energize the 8M contactor
and turn on condenser fan 3.