TECO SG2-20VR-D - PID (Proportion- Integral- Differential) Function Block

Chapter 6 FBD Block Diagram Programming 176
PID (Proportion- Integral- Differential) function block
There is a maximum of 30 PI (PID) function blocks under FBD mode, and the function is same as Ladder mode.
PID computes formula:
()
()
∑
Δ=
−−=
⎭
⎬
⎫
⎩
⎨
⎧
++−=Δ
−=
−−
−
PIPI
PVPVPV
T
T
D
DEV
T
T
EVEVKPI
PVSVEV
nnn
S
D
n
nn
I
s
nnP
nn
21
1
2
Parameters can be constant or other function current value. The output coil will turn ON when either T
S
or K
P
is 0.
Example:
FBD display:
Enable Input
→
Parameter
→
Parameter display:
Parameter display 1 Parameter display 2
PID current value
→
Destination value
→ ←
Proportional gain
Test value
→ ←
Integration time
Sampling time
→
←
Differential time
※ Display PID current value when running mode;
※ Test value (PV) display code A02 when stopping mode, and display current value (as example PV= 00770)
when running mode.
※ Press “SEL+←→” button can convert between display1 and display2.
※ More information about PID function to see Chapter 4: Relay Ladder Logic Programming—PID.
PI: PID current value (-32768~32767)
SV: Destination value (-32768~32767)
PV: Test value (-32768~32767)
T
S
: Sampling time (1~32767 * 0.01s)
K
P
: Proportional gain (1~32767 %)
T
I
: Integration time (1~32767 * 0.1s)
T
D
: Differential time (1~32767 * 0.01s)
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