User Guide

Command Syntax
Siemens Building Technologies, Inc. 3-21
edb Error deadband. This parameter determines how much error
(process variable minus setpoint) must exist before ADAPTS
recalculates its output signal (control variable).
Noisy process variable signals can cause much actuator
movement. Setting edb to a value equal to that of the noise will
eliminate unnecessary actuator movement. Thus, actuator
repositioning, and actuator life, can be affected by the use of this
parameter.
• This parameter can be a point name, local variable
name, or decimal number.
• This value must be greater than or equal to 0.0.
• The drawback when setting edb to a non-zero value is
lack of control accuracy when near setpoint. The
effective setpoint becomes the value of parameter sp +/-
edb.
• Initially set edb to the loop’s maximum allowable
setpoint tolerance.
 For temperature and humidity loops, edb can be
very low–even 0.0 is acceptable
 For static pressure and flow loops, start with 1% to
3% of the maximum input value.
• If small actuator oscillations are observed, edb can be
increased in value until the maximum setpoint tolerance
is reached.
npv Noisy process variable. Noisy means that the value of the
process variable jumps up or down abruptly from one sensor
scan to another.
Some processes inherently create a noisy process variable
signal. An airflow signal, for example, can be very noisy at the
low end of its sensor range due to a lack of resolution. Other
processes can be noisy under certain conditions. For example, a
static pressure signal can be noisy at certain fan speeds and
with a certain sensor positioned too close to the fan.
• This parameter can be an integer, point name, or local
variable name.
• In general, follow these rules:
 npv = 1 (noisy) for a loop with a very noisy pv, such
as airflow or static pressure control. Adaptation is
slowed with npv = 1.
 npv = 0 (not noisy) for a loop with a pv that is not
noisy or only a little noisy, such as temperature
control or humidity control.
APOGEE PPCL User’s Manual
3-22 Siemens Building Technologies, Inc.
err Error reporting point. ADAPTS writes to this point.
• This parameter is entered as a point name or local
variable name.
 A zero indicates no error.
 A non-zero indicates an error.
CAUTION:
Each ADAPTS PPCL line of code must have its
own unique error point. Do not share one error
point among multiple ADAPTS lines.
ADAPTS Example
2000 C ADAPTS CONTROL STATISTICS (LOGICAL
2002 C FIRMWARE) STATIC PRESSURE CONTROL
2004 C DIRECT CONTROL LOOP
2006 C INPUT = %X%SSP
2008 C OUTPUT = %X%LP1
2010 C SETPOINT = %X%SSS
2012 C SAMPLE TIME = 1 SECOND
2014 C GAIN = %X%KC
2016 C TIME CONSTANT = %X%TC
2018 C REVERSE ACTING FLAG = 1
2020 C LOW LIMIT OF INPUT = -0.1
2022 C HIGH LIMIT OF INPUT = 5.0
2024 C LOW LIMIT OF OUTPUT = 0.0
2026 C HIGH LIMIT OF OUTPUT = 100.0
2028 C ERROR DEADBAND = %X%DB1
2030 C NOISY PROCESS VARIABLE = %X%NP1
2034 C ERROR REPORT POINT = %X%ERR
2036 IF(%X%RP1.LT.%X%LP1) THEN GOTO 2042
2038 ADAPTS(%X%SSP,%X%LP1,%X%SSS,1,%X%KC,
%X%TC,1,-0.1,5.0,0.0,100.0,%X%DB1,
%X%NP1,%X%ERR)
2040 C SUPPLY FAN RAMP
2042 TABLE ($SPFRMP,%X%RP1,0,0,180,100)
2044 C SUPPLY FAN VFD SIGNAL
2046 MIN (%X%SVO,%X%LP1,%X%RP1)
......