Hitachi L100 IP Series, Инструкция по эксплуатации

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Chapter 8 – Using the digital operator
8-7
Function Display
*
) Function description / parameter setting range
Standard
setting
Upper/lower limiter, jump frequency
A 61
A 62
Upper fre-
quency limit
Lower fre-
quency limit
0V 10V
f
f
0Hz
t
Acceleration 1
Acceleration
15
25
35
0,5Hz
0,5Hz
15Hz
Jump width
1. jump
( A 64 )
Accel. 2
Frequency
upper limit
A 61
N
Setting range 0.5Hz–360Hz.
(When 0.0 is entered, this function is not active).
0.0
Frequency
lower limit
A 62 N
Setting range 0.5Hz–360Hz
(When 0.0 is entered, this function is not active).
0.0
1. jump frequency
A 63
N
Setting range 0.1Hz–360Hz
(When 0.0 is entered, this function is not active).
0.0
1. jump frequency
width
A 64 N
Setting range 0.1Hz–10Hz
(When 0.0 is entered, this function is not active).
0.5
2. jump frequency
A 65
N
Setting range 0.1Hz–360Hz
(When 0.0 is entered, this function is not active).
0.0
2. jump frequency
width
A 66 N
Setting range 0.1Hz–10Hz
(When 0.0 is entered, this function is not active).
0.5
3. jump frequency
A 67
N
Setting range 0.1Hz–360Hz
(When 0.0 is entered, this function is not active).
0.0
3. jump frequency
width
A 68 N
Setting range 0.1Hz–10Hz
(When 0.0 is entered, this function is not active).
0.5
Function Display
*
) Function description / parameter setting range
Standard
setting
PID control
Introduction
The PID closed loop control has been designed with a control variable of “frequency in Hz” where the proportional
gain (k
p
), the integral gain (T
N
), and the differential gain (T
V
) of the control algorithm can be set independently from
each other. The set value and the actual value are scaled in % (setting range 0–100%). For a better presentation of these
values they can be scaled and displayed in the desired physical engineering unit (e.g. flow or throughput of 0 to 30l/h).
The PID control output is limited to a lower limit of 0 Hz (or the frequency set under
A 62 ) and to the frequency set
under A 04 (or A 61 , respectively) as an upper limit. This ensures that the motor running direction will not be reversed
when a negative deviation is present.
In order to optimize the PID control’s behaviour it is advisable to keep acceleration and deceleration times as short as
possible.
Set value
Function
A 01
is used to configure the method by which the set value is input and also the terminal where it is input:
Set value Parameter Scaling
Not in use 00
Function F 01 02 (0–100%) * (parameter value of function A 75 )
Multistage frequencies A 20 ... A 35 - (0–100%) * (parameter value of function A 75 )
Analog input O (0–10V) 01 0–100% (independent of A 11 thru A 14 )
Analog input OI (4–20mA) 01 0–100% (independent of A 11 thru A 14 )
Actual value
For input of the actual value, one of the two analog inputs available (O or OI) can be used. The adjustment of the
actual value is done using functions
A 11 through A 14 . (This adjustment of the actual value has already been
described as “set value adjustment” earlier in this manual. However, this description is only correct when the PID
( To be continued on next page )
The frequency range set by b 82 (start frequency) and A 04
(maximum frequency) can be further limited using functions A 61 and
A 62
(refer to the upper figure on the left). When a start command is
issued the inverter will output the frequency set under A 62 .
In order to avoid resonances withhin the drive system three jump
frequencies can be configured using the functions
A 63 through A 68 .
In the example (refer to the lower figure on the left) the first jump
frequency (configurable using
A 63 ) is positioned at 15Hz, the second
( A 65 ) at 25Hz, and the third ( A 67 ) at 35Hz. The jump frequency
widths (configurable using
A 64
,
A 66
, and
A 68
) were chosen to be
1Hz each in the example.