Johnson Controls 050, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
82
FORM 100.50-NOM6
ISSUE DATE: 8/07/2017
SECTION 5 – SEQUENCE OF OPERATION
Economizer PI Loop (Proportional and Integral)
The Simplicity Control uses a proportional and integral
logic (PI loop) to control the operation of the damper
actuator. The Simplicity Control monitors the change
in the supply air temperature to the economizer setpoint
verses changes to the output to the damper actuator.
When the supply air temperature is more than 2.0° F
from the economizer setpoint the Simplicity Control
will change the output to the economizer damper 1%
every 2 seconds. If the supply air temperature is within
plus or minus 2.0° F of the economizer setpoint the
Simplicity Control will change the output to the econo-
mizer damper 0.5% every 2 seconds.
ECONOMIZER LOADING
Economizer Loading is a programmable option that
can be used to place an artificial load on the unit to pre-
vent cycling a compressor off when the supply air tem-
perature approaches the “SUPPLY AIR TEMP LIMIT
COOLING SETPOINT” .
The following System Parameters must be pro-
grammed:
• “ECONOMIZER LOADING ENABLE” – must be
enabled under the COOLING SETUP tab in the
Simplicity PC software package.
•
“SUPPLY AIR TEMP LIMIT COOLING
SETPOINT” must be programmed using the
COOLING SETUP tab in the Simplicity PC soft-
ware package.
• “SUPPLY AIR TEMP LIMIT FOR COOLING”
must be enabled using the COOLING SETUP tab
in the Simplicity PC software package.
Constant Volume
The following conditions must be met in order for
Economizer Loading to function:
• The outdoor air temperature must be greater than
the return air temperature.
• Economizer must be installed but not active.
• A call for first stage compressor operation only.
• The unit must be configured as a Constant Volume
unit.
• The unit must be in an occupied or unoccupied
cooling mode.
The sequence of operation is as follows:
• When the supply air temperature is 0.1° F less
than the
“SUPPLY AIR TEMP LIMIT COOLING
SETPOINT”
the economizer damper will start to
open.
• If the economizer damper opens 100% and the
supply air temperature is still 0.1° F less than
the “SUPPLY AIR TEMP LIMIT COOLING
SETPOINT” the Simplicity Control will turn off
the compressor per the Excessive SAT sequence
and close the economizer damper to its minimum
position.
• When the supply air temperature is between
“SUP-
PLY AIR TEMP LIMIT COOLING SETPOINT”
and the “SUPPLY AIR TEMP LIMIT COOLING
SETPOINT” plus 5.0° F the economizer damper
movement will stop and maintain the current posi-
tion.
• When the supply air temperature is equal to 5.1°
F or more above the “SUPPLY AIR TEMP LIMIT
COOLING SETPOINT”
the economizer damper
will close back to its minimum position.
Variable Air Volume
The following conditions must be met in order for
Economizer Loading to function:
• The outdoor air temperature must be greater than
the return air temperature.
• Economizer must be installed but not active.
• A call for first stage compressor operation only.
• The unit must be configured as a Variable Air Vol
-
ume unit.
• The unit must be in an occupied or unoccupied
cooling mode.
The sequence of operation is as follows:
• When the supply air temperature is 5.1° F less
than the
“VAV COOLING SUPPLY TEMP UP-
PER SAT SETPOINT” or “VAV COOLING SUP-
PLY AIR TEMP LOWER SETPOINT” the econo-
mizer damper will start to open.
• If the economizer damper opens 100% and the
supply air temperature is still 5.1° F less than the
“VAV COOLING SUPPLY TEMP UPPER SAT
SETPOINT” or “VAV COOLING SUPPLY AIR
TEMP LOWER SETPOINT”
the Simplicity Con-
trol will turn off the compressor close the econo-
mizer damper to its minimum position.