Hitachi WJ200 Series Software, Инструкция по эксплуатации

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4
−
58
Output Deviation for PID Control
The PID loop error is defined as the
magnitude (absolute value) of the difference
between the Setpoint (target value) and the
Process Variable (actual value). When the
error magnitude exceeds the preset value
for
C044
, the [OD] terminal signal turns ON.
Refer to “PID Loop Operation” on page
4–56.
Option
Code
Terminal
Symbol
Function Name State Description
04
OD Output Deviation for
PID Control ON when PID error is more than the set threshold for
the deviation signal.
OFF when PID error is less than the set threshold for the
deviation signal
Valid for inputs:
11, 12, AL0 – AL2 Example for terminal [11] (default output
configuration shown – see
page 3-90 ):
Example for terminal [AL0], [AL1], [AL2] (requires
output configuration – see
page 4-52 and 3-90 ):
See I/O specs on
page 4-6
Required settings
C044
Notes:
•
The default difference value is set to 3%. To
change this value, change parameter C044
(deviation level).
•
The example circuit for terminal [11] drives a relay
coil. Note the use of a diode to prevent the
negative-going turn-off spike generated by the coil
from damaging the inverter’s output transistor.
t
SP,PV
Setpoint
C044
C044
0
1 [OD]
signal
ON ON
Process variable
RY
Inverter output
terminal circuit
CM2 11
OD
AL1
Power
supply
Load
AL0 AL2
Inverter logic
circuit board OD