Index

62 CNT-APG002-EN
®
E
enable conditions, 24, 25, 27
error
and the velocity model, 7
and throttling range, 9-10
definition, 2
error deadband, 19-21
and sensor resolution, 20
and staging, 20-21, 37
calculating for staged outputs,
21, 40
for modulating outputs, 20
recommended values, 19
execution frequency, see sampling
frequency
F
fail-safe conditions, 24, 25, 27
failure conditions, 24, 27, 34
fans, staging, 37-44
See also staging
formulas, mathematical, 55
frequency, see sampling frequency
G
gains, 10-11
4 to 1 ratio, 11, 52
calculating, 11
derivative, 3, 6, 10-11, 52
integral, 3, 7, 10-11
proportional, 7, 10-11
recommended values, 11
troubleshooting, 45, 46, 50
graphing PID output, 45, 52
H
heating, 16, 17
high setpoint limit, 36
hot water valve
PCL program, 29
TGP program, 30
troubleshooting, 47-50
hysteresis, 42
I
IF statement in PCL, 24
integral
control, 4-5
gain, 3, 7, 10-11
windup, 5, 7
L
Limit block in TGP, 27
low setpoint limit, 36
M
mathematical formulas for PID
control, 55
MAX operator in PCL, 24-25
measured variable, 2
MIN operator in PCL, 24-25
minimum-on and -off times, 20, 42
modulating outputs, 20
O
Or block in TGP, 39
oscillating output, 13, 31, 51
output
at maximum, 45, 46, 51
at minimum, 45, 46, 51
control of actuator, 2
graphing, 45, 52
of PID loop, 2
oscillating, 13, 31, 51
overshoot, 1, 46
undershoot, 46
overshoot, 1, 46
P
PCL, see process control language
PID block in TGP, 26
PID control
definition, 1
mathematical formulas for, 55
overview, 1-2
PID calculations, 3-6
See also derivative control,
integral control, proportional
control
PID Properties dialog box in TGP, 26
pressure control
building, 18, 32-33
duct static, 11, 12, 18
process control language, 23-25
cascade control program, 34
DDC function, 23
DDC Loop Parameter screen, 24
example of PCL program, 25
hot water valve program, 29
IF statement, 24
MAX operator, 24-25
MIN operator, 24-25
relief damper program, 32
staging program, 38
process variable, 2
programming, 23-27
cascade control program, 34, 35
disable conditions, 24, 25, 27
enable conditions, 24, 25, 27
fail-safe conditions, 24, 25, 27
failure conditions, 24, 27, 34
hot water valve program, 29, 30
IF statement, 24
Limit block in TGP, 27
MAX operator, 24-25
MIN operator, 24-25
Or block in TGP, 39
PCL, 23-25
PID block in TGP, 26
PID Properties dialog box in
TGP, 26
relief damper program, 32
staging program, 38
TGP, 26-27
proportional
bias, 3, 40
control, 3, 37, 52, 55
gain, 7, 10-11
R
recommended values, 9-21
action, 18
error deadband, 19
gains, 11
sampling frequency, 14, 53
relief damper, 32-33
PCL program, 32
TGP program, 32
resolution, sensor, 20, 32
reverse action, 17, 52
routine, see programming