Learning Protection Features
The inverter calculates the average output value for
10 seconds before the loss of the speed command
and uses it as the speed reference.
The inverter operates at the frequency set at PRT-
14 (Lost Preset F).
PRT-15 AI Lost
Level,
PRT-13 Lst Cmd
Time
Configure the voltage and decision time for speed command loss when
using analog input.
Based on the values set at IN-08 and IN-12, a
protective operation starts when the input signal is
reduced to half of the initial value of the analog input
set using the speed command (DRV-01) and it
continues for the time (speed loss decision time) set
at PRT-13 (Lost Cmd Time). For example, set the
speed command to ‗2 (V1)‘ at DRV-07, and set IN-
06 (V1 Polarity) to ‗0 (Unipolar)‘. When the voltage
input drops to less than half of the value set at IN-08
(V1 Volt x 1), the protective function is activated.
The protective operation starts when the signal
becomes smaller than the initial value of the analog
input set by the speed command and it continues for
the speed loss decision time set at PRT-13 (Lost
Cmd Time). Codes IN-08 and IN-12 are used to set
the standard values.
If the set value of the IN-08 and IN-12 is ‗0,‘ the LostCmd function does
not operate.
In situations where speed commands are lost, set the operation mode
(PRT-12 Lost Cmd Mode) to ‗5 (Lost Preset)‘. This operates the
protection function and sets the frequency so that the operation can
continue.