Specifications

Process Flow
IM/265/7/9/ADD/FF-EN_01 Connection to FOUNDATION Fieldbus 69
12.5 PID algorithm
M00519
FF_deviation
if FF.status(k-1) = GOOD and FF.status(k-2) = BAD
{
FF_deviation = FF(k) - FF(k-1)
}
tk -tk-1 = time_const
RESET
Z
-1
+time_const
RESET
++
B
time_const
BAL_TIME
++
+
out
out
out_deviation
HI_LIM
LO_LIM
out_deviation
if
| last_I_part|<|out_deviation |
{
windup = last_I_part
}
else
{
windup = out_deviation
}
-
P
Z
-1
FF_deviation
+
Z
-1
-1
B
-
(setpoint)
(process)
+
[e]
T1_RATE
RESET
+
D
I
windup
RATE
RATE
time_const
+
-
BAL_TIME
Z
raw_value
pv_value
deviation
GAMMA
BETA
GAIN
RATE
Fig. 17: PID algorithm