TECO SG2-12HT-D - PID (Proportion- Integral- Differential)

Chapter 5 Relay Ladder Logic Programming 121
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17BPID (Proportion- Integral- Differential)
The SG2 smart relay includes 15 PID coils that can be used throughout a program. The PID function performs a
simple integral-math-calculation which is according to the equation as shown in below. There are 9 parameters for
proper configuration. The table below describes each configuration parameter, and lists each compatible element for
configuring PID.
The parameters from ① to ⑦ can be a constant or refer to the current value of other function The error coil
will turn ON when either T
S
or K
P
equal to 0. But it will do nothing if the output coil is NOP. The output coil will
turns OFF when the result is in the range or the function is disabled.
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
The example below shows how to configure PID function.
Symbol Description
①
PI: PID current value (-32768~32767)
②
SV: Set value (-32768~32767)
③
PV: Feedback value (-32768~32767)
④
T
S
: Sampling time (1~32767 * 0.01s)
⑤
K
P
: Proportional gain (1~32767 %)
⑥
T
I
: Integration time (1~32767 * 0.1s)
⑦
T
D
: Differential time (1~32767 * 0.01s)
⑧
Error output coil (M, N, NOP)
⑨
PID code (PI01~PI0F)
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