User Guide

Command Syntax
Siemens Building Technologies, Inc. 3-17
Suggested Sample Times
Temperature Loops (single input, single output)
• 5 seconds for fast loops;
• 10 seconds for slow loops.
Humidity Loops
• 5 to 10 seconds for return air or space loop;
• 1 or 2 seconds for a discharge air loop.
Flow and Static Pressure Loops
• 1 or 2 seconds
kc Control gain.
• This parameter can be a point name, local variable
name, or decimal number.
• This value must be greater than 0.
• Since ADAPTS will adapt to the process it is controlling,
set kc to 3.0 for both English and SI Unit applications.
tc Time constant (in seconds). The Time Constant value is a
rough estimate of the time constant of the process.
• This parameter can be a point name, local variable
name, or decimal number.
• This value must be greater than or equal to 3 times the
st value.
Note: Increasing the value of tc slows down the adaptation
process.
Cooling Coils
Use the following formula:
actuatorcc
T
sensor
T
waterchilled
sL
air
sL
or
GPM
CFM
tc ++=
max
/
max
/
0.2
max
max
25.0
Where:
tc = ADAPTS cooling time constant parameter entry (in
seconds).
CFM
max
= Maximum or design airflow rate in cubic feet per
minute.
L/s
air max
= Maximum or design airflow rate in liters per second.
GPM
max
= Maximum or design chilled water flow rate in gallons
per minute.
APOGEE PPCL User’s Manual
3-18 Siemens Building Technologies, Inc.
L/s
chilled water max
= Maximum or design chilled water rate in liters
per second.
T
sensor
= time constant of the supply air sensor; typically about 30
seconds.
T
cc actuator
= stroke time of the cooling coil actuator; typically 30
seconds.
Heating Coils
Use the following formula:
actuatorhcsensor
waterhot
maxair
TT
sL
sL
or
GPM
CFM
tc ++=
maxmax
max
/
/
15.002.0
Where:
tc = ADAPTS heating time constant parameter entry (in
seconds).
CFM
max
= Maximum or design airflow rate in cubic feet per
minute.
L/s
air max
= Maximum or design airflow rate in liters per second.
GPM
max
= Maximum or design hot water flow rate in gallons per
minute.
l/s
hot water max
= Maximum or design hot water rate in liters per
second.
T
sensor
= time constant of the supply air sensor; typically about 30
seconds.
T
hc actuator
= stroke time of the heating coil actuator; typically 30
seconds.
Mixed Air Temperature
Use the following formula:
actuatordampersensorma
TTtc
+
=
Where:
tc = ADAPTS mixed air temperature time constant parameter
entry (in seconds); typically 40 seconds.
T
ma sensor
= time constant of the mixed air temperature sensor;
typically about 30 seconds.