6. Programming Features
61
Operating a Coasting Motor without Tripping
To operate a coasting motor without tripping, use the SPEED SEARCH
command or DC injection braking at startup.
SPEED SEARCH Command
Restarts a coasting motor without stopping it. This function enables
smooth switching between motor commercial power supply operation
and Inverter operation.
Set a Multi-function Input Selection (n36 to n39) to 14 (SEARCH com-
mand from maximum output frequency) or 15 (SEARCH command
from set frequency).
Build a sequence so that a FWD (REV) RUN command is input at the
same time as the SEARCH command or after the SEARCH command.
If the RUN command is input before the SEARCH command, the
SEARCH command will be disabled.
Time Chart at SEARCH Command Input
DC Injection Braking at Startup (n52, n54)
Restarts a coasting motor after stopping it. Set the DC injection braking
time at startup in n54 in units of 0.1 second. Set the DC Injection Brak-
ing Current in n52 in units of 1% (Inverter rated current =100%). When
the setting of n54 is 0, DC injection braking is not performed and accel-
eration starts from the minimum output frequency.
When n52 is set to 0, acceleration starts
from the minimum output frequency after
baseblocking for the time set in n54.
FWD (REV) RUN Command
SEARCH Command
Max. Output Frequency or
Frequency Reference at
RUN Command Input
Output Frequency
Min. Baseblock
Time (0.5 s)
Speed
Search
Operation
Speed Agreement
Detection
Min. Output
Frequency
n14
DC Injection Braking
Time at Startup
n54
