Carrier Weathermaster 48P2030-100 Controls, Start-Up, Operation, Service, And Troubleshooting page 82

Fan Track Learn Enable (FT.CF)
For BP.CF = 5, this return/exhaust control configuration se-
lects whether the fan tracking algorithm will make corrections
over time and add a learned offset to FT.ST. If this configura-
tion is set to No, the unit will try to control the delta cfm value
between the supply and return VFDs only based on FT.ST.
Fan Track Initial DCFM (FT.ST)
For BP.CF = 5, this return/exhaust control configuration is the
start point upon which corrections (offset) are made over time
when FT.CF = Yes. It is the constant control point for delta
cfm control when FT.CF = No.
Fan Track Max Clamp (FT.MX)
For BP.CF = 5, this return/exhaust control configuration is the
maximum positive delta cfm control value allowed unless out-
door air cfm control is available and then the delta cfm control
value would be clamped to the outdoor air cfm value directly
(see the Economizer section on page 72 for a description of
outdoor air cfm configuration).
Fan Track Max Correction (FT.AD)
For BP.CF = 5, this return/exhaust control configuration is the
maximum correction allowed every time a correction is made
based on FT.TM. This configuration is only valid when FT.CF =
Yes.
Fan Track Internal EEPROM (FT.OF)
For BP.CF = 5, this return/exhaust control internal EEPROM
value is a learned correction that is stored in non-volatile RAM
and adds to the offset when FT.CF = Yes. This value is stored
once per day after the first correction. This configuration is
only valid when FT.CF = Yes.
Fan Track Internal Ram (FT.RM)
For BP.CF = 5, this return/exhaust control internal value is not
a configuration but a run time correction that adds to the offset
throughout the day when FT.CF = Yes. This value is only valid
when FT.CF = Yes.
Fan Track Reset Internal (FT.RS)
This option is a one time reset of the internal RAM and internal
EEPROM stored offsets. If the system is not set up correctly
and the offsets are incorrect, this learned value can be reset.
Supply Air cfm Config (SCF.C)
For BP.CF = 5, this configuration is set at the factory depending
on whether an air foil or forward curve supply air fan is being
used. This information is then used by the control to determine the
correct cfm tables to be used when measuring supply air cfm.
Building Pressure Run Rate (BP.TM)
For BP.CF = 2, 3, 4, and 5, this configuration is the PID run
time rate.
Building Pressure Proportional Gain (BP.P)
For BP.CF = 2, 3, 4, and 5, this configuration is the PID Pro-
portional Gain.
Building Pressure Integral Gain (BP.I)
For BP.CF = 2, 3, 4, and 5, this configuration is the PID Inte-
gral Gain.
Building Pressure Derivative Gain (BP.D)
For BP.CF = 2, 3, 4, and 5, this configuration is the PID Deriv-
ative Gain.
BUILDING PRESSURE CONTROL OPERATION
 
Configuration BP BP.CF = 1 (Constant Volume 2-Stage
Control)
Two exhaust fan relays will be turned on and off based on econo-
mizer position to maintain building pressure control. The two trip
set points are Configuration

BP BP.P2. If the economizer position is greater than or equal to
BP.P1, then power exhaust relay 1 is energized, turning on the first
 
BP BP.P1 and Configuration
stage. A 60-second timer is initialized. If the economizer falls 5%
below the BP.P1, then the power exhaust fan relay is turned off. If
the economizer position is less than BP.P1 and the 60-second tim-
er has expired, the power exhaust fan relay is turned off. The same
logic applies to the second power exhaust fan relay, except the
BP.P2 trip point is monitored. If the economizer position is greater
than or equal to BP.P2, then power exhaust relay 2 is energized,
turning on the second stage. A 60-second timer is initialized. If the
economizer is 5% below the BP.P2, the second power exhaust fan
relay is turned off. If the economizer is less than BP.P2 and the 60-
second timer has expired, the power exhaust fan relay is turned
off.

Configuration BP
Control is accomplished with two Belimo MP communicating
actuators in tandem and 2 exhaust fan relays. If building pressure

(Pressures AIR.P
point (BP.SP) and the supply fan is on, building pressure control
is initialized. Thereafter, if the supply fan relay goes off or if the
building pressure drops below the BP.SP minus the building
pressure set point offset (BP.SO) for 5 continuous minutes,
building pressure control will be stopped. Any time building
pressure control becomes active, the exhaust fan relay turns on,
starting the dual exhaust fan motors. After the exhaust fan relay
turns on, control is performed with a PID loop where:
Error = BP – BP.SP
K = 1000 * BP.TM / 60 (normalize the PID control for run
rate)
P = K * BP.P * (error)
I = K * BP.I * (error) + "I" calculated last time through the
PID
D = K * BP.D * (error – error computed last time through
the PID)
Power exhaust control signal (limited between BP.MN and
(BP.1M/BP.2M) %) = P + I + D

Configuration BP
Fan Motors)
The VFD controlling power exhaust consists of an exhaust fan

VFD (Outputs FANS
haust relay (Outputs

(Pressures AIR.P
point (BP.SP) and the supply fan is on, then building pressure
control is initialized. Thereafter, if the supply fan relay goes off
or if the building pressure drops below the BP.SP minus the
building pressure set point offset (BP.SO) for 5 continuous min-
utes, building pressure control will be stopped. The 5-minute
timer will continue to re-initialize while the VFD is commanded
to a position > 0%. If the building pressure falls below the set
point, the VFD will slow down automatically. Any time building
pressure control becomes active, the exhaust fan relay turns on
which energizes the exhaust fan VFD. Control is performed with
a PID loop where:
Error = BP – BP.SP
K = 1000 * BP.TM/60 (normalize the PID control for run
rate)
P = K * BP.P * (error)
I = K * BP.I * (error) + "I" calculated last time through the
PID
D = K * BP.D * (error – error computed last time through
the PID)
VFD control signal (clamped between BP.MN and
BP.MX%) = P + I + D
NOTE: Do not change values of PID set point without approval
from Carrier.
BP.CF = 4 (High-Capacity Exhaust Control)

Control is accomplished with a VFD and two exhaust fan relays.
High-capacity power exhaust consists of an exhaust fan VFD
 
(Outputs FANS
82

BP.CF = 2 (Modulating Power Exhaust)

BP) rises above the building pressure set

BP.CF = 3 (VFD Controlling Exhaust

E.VFD) enabled by one power ex-
 
FANS P.E.1). If building pressure

BP) rises above the building pressure set
E.VFD) enabled by one power exhaust relay