Hitachi SJ Series, User Manual

Page: 267 / 786

12-10-12
Chapter 12 Inverter Functions
Output of ± switching PID1 deviation
• Output is feasible by switching ± PID1 deviation.
• When PID1 deviation minus [AH-02] is 00,
calculation will be performed by (PID target value -
FB value). With 01, it will be the same operation as
(FB value - PID target value).
• Use this when the polarity of deviation of PID target
value and FB value does not much with the
command from the inverter due to sensor
characteristics, etc.
PID1 feed-forward value selection
• Select PID1-feed forward value.
e.g.) Control the compressor for refrigerator.
When the temperature sensor specification is -20
to 100
°
C: 0 to 10 (V) and the target value is 0
°
C,
and if the current temperature is 10
°
C, the speed
will decrease in normal PID control as it is (FB
value) > (PID target value).
• The inverter will raise the speed if [AH-02] = 01 is
set.
• Feed-forward control operates by setting [AH-70] to
anything other than 00 (None).
A
Ａ
PID target value
Feedback data value
+
00
01
PID1 deviation
minus 1
[AH-02]
-
×
(-1)
PID calculation
[db-51]
PID feed-forward value
Input
destination 1
[AH-70]
(00~06)
01
(00: Disable)
Analog input Ai1 to Ai6 (01 to 06)
[db-64]