Eaton ELC-PB, Руководство по программированию

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3 . I n s t r u c t i o n S e t
M N050 03003E F or mo re infor ma tio n vi sit:
w w w. e a t o n . c o m
3-257
Device No. Function Set-point range Explanation
S
3
+13:
~
S
3
+19:
For system use only.
4. When a parameter setting exceeds its range, the upper / lower bound will be selected as the
set value. However, if the control direction (DIR) exceeds the available range, it will be set to 0.
5. The PID instruction can be used in interrupt subroutines, step ladders and with the CJ
instruction.
6. The maximum error of sampling time T
S
= - (1 scan time + 1ms) ~ + (1 scan time). When the
error affects the output, fix the scan time or execute the PID instruction in timed interrupt.
7. The PV parameter of the PID instruction must be stable before the PID operation executes.
8. For the 32-bit instruction,
S
3
occupies 21 registers. In the program example above, the area
designated in
S
3
will be D100 ~ D120. Before execution of the PID instruction, users must
move the parameters to the designated register area with a MOV instruction. If the designated
registers are latched, use the MOVP instruction to transmit all parameters once. If
S
3
+1~3: are
out of range, either the upper or lower limit value will be used.
9. Parameter table of 32-bit
S
3
:
Device No. Function Set-point range Explanation
S
3
: Sampling time (T
S
)
1~2,000
(unit: 10ms)
Time interval between PID
calculations and updates of MV. If
T
S
= 0, the PID instruction will not
be enabled. If T
S
is less than 1
program scan time, the PID
instruction sets
S
3
to 1 program
scan time, i.e. the value of T
S
cannot be less than one program
scan time.
S
3
+1:
Proportional
gain
(K
P
)
0~30,000(%)
The proportion for minimizing the
error between SV and PV.
Integration gain (K
I
) 0~30,000(%)
The proportion for minimizing the
integral value (The accumulated
error). For control mode K0~K2,
K5.
S
3
+2:
Integral time constant
(T
I
)
0~30,000 (ms) For control mode K10