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

Table 50 — Static Pressure Control Configuration
ITEM EXPANSION RANGE UNITS CCN POINT DEFAULT
SP SUPPLY STATIC PRESS.CFG.
SP.CF Static Pressure Config Enable/Disable STATICFG Disable
SP.S Static Pressure Sensor Enable/Disable SPSENS Disable
SP.LO Static Press. Low Range –10 - 0 in. W.C. SP_LOW 0
SP.HI Static Press. High Range 0 - 10 in. W.C. SP_HIGH 5
SP.SP Static Pressure Setpoint 0 - 5 in. W.C. SPSP 1.5
SP.MN VFD Minimum Speed 0 - 100 % STATPMIN 20
SP.MX VFD Maximum Speed 0 - 100 % STATPMAX 100
SP.FS VFD Fire Speed Over. 0 - 100 % STATPFSO 100
SP.RS Stat. Pres. Reset Config 0 - 4 SPRSTCFG 0
SP.RT SP Reset Ratio (/dF) 0 - 2.00 SPRRATIO 0.2
SP.LM SP Reset Limit in iwc () 0 - 2.00 SPRLIMIT 0.75
SP.EC SP Reset Econo.Position 0 - 100 % ECONOSPR 5
S.PID STAT.PRESS.PID CONFIGS
SP.TM Static Press. PID Run Rate 5 - 120 sec SPIDRATE 15
SP.P Static Press. Prop. Gain 0 - 5 STATP_PG 0.5
SP.I Static Pressure Intg. Gain 0 - 2 STATP_IG 0.5
SP.D Static Pressure Derv. Gain 0 - 5 STATP_DG 0.3
Static Pressure Reset Configuration (SP.RS) — This option
is used to configure the static pressure reset function. When
SP.RS = 0, there is no static pressure reset via an analog input.
When SP.RS = 1, there is static pressure reset based on the
CEM 4-20MA input and ranged from 0 to 3 in. wg. When
SP.RS = 2, there is static pressure reset based on RAT and
defined by SP.RT and SP.LM. When SP.RS = 3, there is
static pressure reset based on SPT and defined by SP.RT and
SP.LM. When SP.RS = 4, there is VFD speed control where
0 mA = 0% speed and 20 mA = 100% (SP.MN and SP.MX will
override).
Static Pressure Reset Ratio (SP.RT) — This option defines
the reset ratio in terms of static pressure versus temperature.
The reset ratio determines how much the static pressure is
reduced for every degree below set point for RAT or SPT.
Static Pressure Reset Limit (SP.LM) — This option defines
the maximum amount of static pressure reset that is allowed.
This is sometimes called a “clamp.”
NOTE: Resetting static pressure via RAT and SPT is primarily
a constant volume application which utilizes a VFD. The reasoning
is that there is significant energy savings in slowing
down a supply fan as opposed to running full speed with
supply air reset. Maintaining the supply air set point and
slowing down the fan has the additional benefit of working
around dehumidification concerns.
Static Pressure Reset Economizer Position (SP.EC) — This
option effectively resets ECONOMIN to fully occupied ventilation
position, to account for the drop in static pressure during
static pressure reset control. The static pressure reset for the
calculation cannot be larger than the supply air static set point
(SPSP).
The calculation is as follows:
(Static Pressure Reset/SPSP) x (ECONOSPR – ECONOMIN)
As an example, the static pressure set point (SPSP) =
1.5 in. wg. The current static pressure reset is set to 0.5 in. wg.
The settings for ECONOSPR = 50% and ECONOMIN = 20%.
Therefore, the amount to add to the economizer’s
ECONOMIN configuration is: (0.5/1.5) x (50-20) = 10%. In
effect, for the positioning of the economizer, ECONOMIN
would now be replaced by ECONOMIN + 10%.
Static Pressure PID Config (S.PID) — Static pressure PID
configuration can be accessed under this heading in the ConfigurationSP
submenu. Under most operating conditions the
control PID factors will not require any adjustment and the
factory defaults should be used. If persistent static pressure
65
fluctuations are detected, small changes to these factors may
improve performance. Decreasing the factors generally reduce
the responsiveness of the control loop, while increasing the
factors increase its responsiveness. Note the existing settings
before making changes, and seek technical assistance from
Carrier before making significant changes to these factors.
Static Pressure PID Run Rate (S.PIDSP.TM) — This is the
number of seconds between duct static pressure readings taken
by the ComfortLink PID routine.
Static Pressure Proportional Gain (S.PIDSP.P) — This is
the proportional gain for the static pressure control PID control
loop.
Static Pressure Integral Gain (S.PIDSP.I) — This is the
integral gain for the static pressure control PID control loop.
Static Pressure Derivative Gain (S.PIDSP.D) — This is the
derivative gain for the static pressure control PID control loop.
STATIC PRESSURE RESET — The configuration for Static
Pressure Reset is found under ConfigurationSP.
ITEM EXPANSION RANGE CCN POINT DEFAULT
SENSSP.RS
Static Press.
Reset Sensor.
Enable/
Disable
SPRSTSEN Disable
Static Pressure Reset Sensor (SP.RS) — If the outdoor air
quality sensor is not configured (ConfigurationIAQ
AQ.CFOQ.A.C=0), then it is possible to use the outdoor
air quality sensor location on the CEM board to perform static
pressure reset via an external 4 to 20 mA input. Enabling this
sensor will give the user the ability to reset from 0 to 3-in. wg
of static pressure. The reset will apply to the supply static
pressure set point (ConfigurationSPSP.SP), where 4 mA
= 0-in. wg and 20 mA = 3-in. wg.
As an example, the static pressure reset input is measuring
6 mA, and the input is resetting 2 mA of its 16 mA control
range. The 4 to 20 mA range corresponds directly to the 0 to
3 in. wg of reset. Therefore 2 mA reset is 2/16 * 3-in. wg =
0.375-in. wg of reset. If the static pressure set point (SP.SP) =
1.5-in. wg, then the static pressure control point for the system
will be reset 1.5 – 0.375 = 1.125-in. wg.
For third party 4 to 20 mA SP reset, wire the input to TB202
terminals 6 and 7.
For reset via a connected ComfortID system, the Linkage
Coordinator terminal monitors the primary-air damper position
of all the terminals in the system. It then calculates the amount of
supply static pressure reduction necessary to cause the most
open damper in the system to open more than the minimum