Controls, Start-Up, Operation, Service and ... - Climayoreo

Configuring the Economizer to Communicate Via Actuator
Serial Number — Every actuator used in the P Series control
system has its own unique serial number. The rooftop control
uses this serial number to communicate with the actuator.
These serial numbers are programmed at the factory and
should not need changing. Should field replacement of an actuator
become necessary, it will be required to configure the serial
numbers of the new actuator. Four individual numbers make
up this serial number and these can be programmed to match
the serial number of the actuator in its Economizer Actuator
Configs group, ACT.C (SN1.1, SN1.2, SN1.3, SN1.4, SN2.1,
SN2.2, SN2.3, SN2.4).
NOTE: The serial numbers for all actuators can be found
inside the control doors of the unit as well as on the actuator
itself. If an actuator is replaced in the field, it is a good idea to
remove the additional peel-off serial number sticker on the
actuator and cover up the old one inside the control doors.
Control Angle Alarm Configuration — The economizer actuator
determines its end stops through a calibration at the
factory. Field-installed actuators may be calibrated in the
Service Test mode. When an actuator learns its end stops
through calibration, it also determines its control angle. The
actuator will resolve this control angle and express its operation
in a percent (%) of this learned range.
If the economizer has not learned a sufficient control angle
during calibration, the economizer damper will be unable
to control ventilation and free cooling. For this reason the
economizer actuator used in the P Series control system has a
configurable control angle alarm low limit (Configuration
ECONACT.CC.A.L1 or C.A.L2). If the control angle
learned through calibration is less than C.A.L1 or C.A.L2, an
alert will occur and the actuator will not function.
NOTE: This configuration does not typically need adjustment.
It is configurable for the small number of jobs which may
require a custom solution or workaround.
UNOCCUPIED ECONOMIZER FREE COOLING — This
Free Cooling function is used to start the supply fan and use
the economizer to bring in outside air when the outside
temperature is cool enough to pre-cool the space. This is done
to delay the need for mechanical cooling when the system
enters the occupied period. This function requires the use of a
space temperature sensor.
When configured, the economizer will modulate during an
unoccupied period and attempt to maintain space temperature
to the occupied cooling set point. Once the need for cooling has
been satisfied during this cycle, the fan will be stopped.
Configuring the economizer for Unoccupied Economizer
Free Cooling is done in the UEFC group. There are three
configuration options, FC.CF, FC.TM and FC.LO.
Unoccupied Economizer Free Cooling Configuration
(FC.CF) — This option is used to configure the type of unoccupied
economizer free cooling control that is desired.
0 = disable unoccupied economizer free cooling
1 = perform unocc. economizer free cooling as available during
the entire unoccupied period.
2 = perform unocc. economizer free cooling as available,
FC.TM minutes before the next occupied period.
Unoccupied Economizer Free Cooling Time Configuration
(FC.TM) — This option is a configurable time period, prior to
the next occupied period, that the control will allow unoccupied
economizer free cooling to operate. This option is only
applicable when FC.CF = 2.
Unoccupied Economizer Free Cooling Outside Lockout
Temperature (FC.LO) — This configuration option allows
the user to select an outside-air temperature below which unoccupied
free cooling is not allowed. This is further explained in
the logic section.
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Unoccupied Economizer Free Cooling Logic — The following
qualifications that must be true for unoccupied free cooling
to operate:
• Unit configured for an economizer
• Space temperature sensor enabled and sensor reading
within limits
• Unit in the unoccupied mode
• FC.CF set to 1 or FC.CF set to 2 and control is within
FC.TM minutes of the next occupied period
• Not in the Temperature Compensated Start mode
• Not in a cooling mode
• Not in a heating mode
• Not in a tempering mode
• Outside-air temperature sensor reading within limits
• Economizer would be allowed to cool if the fan were
requested and in a cool mode
• OAT > FC.LO (1.0° F hysteresis applied)
• Unit not in a fire smoke mode
• No fan failure when configured to for unit to shut down
on a fan failure
If all of the above conditions are satisfied:
Unoccupied Economizer Free Cooling will start when both of
the following conditions are true:
{SPT > (OCSP + 2)} AND {SPT > (OAT + 8)}
The Unoccupied Economizer Free Cooling Mode will stop
when either of the following conditions are true:
{SPT < OCSP} OR {SPT < (OAT + 3)} where SPT = Space
Temperature and OCSP = Occupied Cooling Set Point.
When the Unoccupied Economizer Free Cooling mode is
active, the supply fan is turned on and the economizer damper
modulated to control to the supply air set point (Setpoints
SASP) plus any supply air reset that may be applied (Inputs
RSETSA.S.R).
OUTDOOR AIR CFM CONTROL — If an outdoor air cfm
flow station has been installed, the economizer is able to
provide minimum ventilation based on cfm, instead of
damper position. The outdoor air cfm reading can be found in
InputsCFMO.CFM. During cfm control, the economizer
must guarantee a certain amount of cfm at any time for ventilation
purposes. If the outdoor air cfm measured is less than the
current calculated cfm minimum position, then the economizer
will attempt to open until the outdoor air cfm is greater than or
equal to this cfm minimum position. The following options are
used to program outside air cfm control.
Outdoor Air Cfm Sensor Enable (OCF.S) — If this option is
enabled, the outdoor air cfm sensor will be read and outside air
cfm control will be enabled.
Economizer Minimum Flow Rate (O.C.MX) — This option
replaces the Economizer Minimum Position (Configuration
ECONEC.MN) when the outdoor air cfm sensor is
enabled.
IAQ Demand Vent Minimum Flow Rate (O.C.MN) — This
option replaces the IAQ Demand Ventilation Minimum
Position (ConfigurationIAQDCV.CIAQ.M) when the
outdoor air cfm sensor is enabled.
Economizer Minimum Flow Deadband (O.C.DB) — This
option defines the deadband of the cfm control logic.
The configurable deadband is added to the economizer’s
minimum cfm position and creates a range (ECMINCFM to
ECMINCFM ± OACFM_DB) where the economizer will not
attempt to adjust to maintain the minimum cfm position.
Increasing this deadband value may help to slow down excessive
economizer movement when attempting to control to a
minimum position at the expense of bringing in more ventilation
air than desired.
ECONOMIZER OPERATION CONFIGURATION — The
configuration items in the E.CFG menu group affect how