Hitachi NES1-002LB, Краткое руководство пользователя

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Chapter 7 Explanation of Functions
7 - 56
7.7.3 Free-run stop (FRS) function
The free-run stop (FRS) function allows you to shut off the inverter output to let the motor start
free-running.
You can effectively use this function when stopping the motor with a mechanical brake (e.g.,
electromagnetic brake). If an attempt is made to forcibly stop the motor with a mechanical brake while the
inverter keeps its output, the inverter may trip because of overcurrent.
To use this function, assign function "11" (FRS) to one of the terminal [1] to [5] functions (C001 to C005).
The free-run stop (FRS) function operates as long as the FRS terminal is on. When the FRS terminal is
turned off, the inverter restarts the motor after the retry wait time (b003). However, the inverter does not
restart the motor if the digital operator (02) has been specified for the run command source setting (A002).
To restart the motor in such status, enter a new operation command.
You can select the inverter output mode for restarting with the restart mode after FRS (b088) from starting
the motor with 0 Hz and restarting with active matching frequency. (See examples 1, 2.)
Even when restarting with active matching frequency has been selected, the inverter restarts the motor
with 0 Hz if it detects a frequency lower than the restart frequency threshold (b007).
The settings, including that of the FRS terminal, which you make for this function will affect the inverter
operation at recovery of the motor from the free-running status.
Item Function code Data or range of data Description
Restart mode after
FRS
b088
00 Start with 0 Hz (See example 1.)
01
Restart with active matching frequency
(See example 2.)
Retry wait time before
motor restart
b003 0.3 to 100. (s) Time to wait until restarting the motor
Restart frequency
threshold
b007 0.00 to 400.0 (Hz)
Setting of the minimum level for frequency
adjustment
Active frequency
matching, scan start
frequency
b028
"0.20 x rated current" to
"2.00 x rated current"
Current limit for restarting with active matching
frequency
Active frequency
matching, scan-time
constant
b029 0.10 to 3000.0 (s)
Duration of frequency lowering when restarting
with active matching frequency
Active frequency
matching, restart
frequency select
b030
00
Frequency set when the inverter output has
been shut off
01 Maximum frequency
02 Newly set frequency
(Example 1) Restarting with 0 Hz (Example 2) Restarting with active matching frequency
The inverter restarts the motor with 0 Hz
regardless of the motor speed. The setting of retry
wait time is ignored.
If the inverter restarts the motor with 0 Hz when
the motor speed is high, the inverter may trip
because of overcurrent.
After the retry wait time (b003), the inverter restarts the motor
with the frequency set as "b030". The inverter subsequently
decelerates the motor according to the setting of "b029" while
maintaining the output current at the level specified for "b029".
When the output voltage matches the frequency, the inverter
re-accelerates the motor up to the frequency that was set
when the inverter shut off the output to the motor before the
restart.
If the inverter trips because of overcurrent when it restarts the
motor with input frequency, reduce the setting of "b028".
Free-running
Restarting with 0 Hz
0
FW
Motor
speed
FRS
FW
FRS
b028
Output
current
Inverter
output
f
Deceleration according
to the setting of "b029"
Frequency selected as the
setting of "b030"
b003
Motor
speed