ADAPTS(PV,CV,SP,ST,KC,TC,RA,LLPV,HLPV,LLCV,HLCV,EDB,NPV,ERR)
PV. Point name of the process variable being controlled or regulated. Process Var is usually an LAI point, but can be an LAO point, which represents supply air temperature. It's value should be between -50.0 and 150.0.
CV. Point name or local varable name for the output signal (controlled variable). This signal is 0.0 to 100.0 percent, direct acting, and is intedted to go to TABLE statements; one for each output actuator point (example, heating, dampers, and cooling).
Set Point. Set point for the loop against which the process variable is compared. This parameter can be a point name, decimal number, or local variable. Set point should represent the same engineering units as the process variable.
ST. Sample Time. This is the time, in seconds, between two successive starts of execution of the ADAPTS algorithm. It is also the time interval between two samples of data by ADAPTS. The minimum Sample Time allowed is 1 second. The Sample Time must be entered as an integer, point name or local variable. The Sample Time must be smaller than or equal to one-third of the smallest Time Constant.
KC. Control Gain. Its value must be greater than 0. KC should be set to 3. This parameter can be enetered as a point name, local variable, or decimal.
TC. Time Constant, in seconds. TC should be set to the sum of the time constraints of the control loops sensor, actuator, and coil (if applicable). This value must be greater than or equal to 3 times the Sample Time (ST). This parameter can be entered as a point name, local variable, or decimal.
RA. Reverse Acting flag (1 = reverse acting; 0 = direct acting) This defines the action of the ADAPTS controller. Reverse acting means the (output) point name or local variable name of the loop output (CV)decreases as the (input) process variable (PV) increases. This parameter can be entered as a point name, local variable, or an integer.
LLPV. Low Limit of Process Variable. Its value must be less than (HLPV). This parameter can be entered as a point name, local variable, or decimal. The LLPV value is typically the lowest value that the process variable (PV) is expected to achieve.
Example 1: For static pressure control, enter a small negative value (-0.1) to cover the possibility of a miscalibrated sensor or small negative air pressures when the fan is off.
Example 2: For supply air temperature control with mixed air dampers, use 30°F. The mixed air dampers should prevent any lower temperatures from entering the supply duct even if the heating coil is not operating or hot water is absent.
HLPV. High Limit of Process Variable. Its value must be greater than llpv. This parameter can be entered as a point name, local variable, or decimal. The hlpv value is typically the highest value that the process variable (PV) is expected to achieve.
Example 1: For static pressure control, enter the highest pressure that will occur in the supply duct. The highest pressures occur on startup and when there are large upsets.
Example 2: For supply air temperature control use 130°F.
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