Preventing Overvoltage During Deceleration (Stall Prevention During Deceleration Function) - YASKAWA CIMR-F7A Instruction Manual

Preventing Overvoltage During Deceleration (Stall Prevention During
Deceleration Function)
The Stall Prevention During Deceleration function makes the rate of deceleration more gentle to suppress
increases in DC bus voltage when the DC bus voltage exceeds the set value during motor deceleration.
This function automatically lengthens the deceleration time with respect to the bus voltage, even if the decel-
eration time has been set to a considerably small value.
If L3-04 is set to 1 or 2, when the main circuit DC voltage approaches the stall prevention level during decel-
eration, deceleration stops, and when deceleration falls below the level, is restarted. Using this operation,
deceleration time is automatically lengthened. If L3-04 is set to 1, deceleration time returns to the set value,
and if L3-04 is set to 2, deceleration is automatically adjusted to a faster deceleration time within the range of
the stall prevention level during deceleration.
Related Constants
Con-
stant
Number
Stall preven-
L3-04 tion selection
during decel
* When using flux vector control, 0 to 2.
-32
6
Name Description
0: Disabled (Deceleration as
set. If deceleration time is
too short, a main circuit
overvoltage may result.)
1: Enabled (Deceleration is
stopped when the main
circuit voltage exceeds the
overvoltage level.
Deceleration restarts when
voltage is returned.)
2: Intelligent deceleration
mode (Deceleration rate is
automatically adjusted so
that in Inverter can
decelerate in the shortest
possible time. Set
deceleration time is
disregarded.)
3: Enabled (with Braking
Resistor Unit)
When a braking option (Braking
Resistor, Braking Resistor Unit,
Braking Unit) is used, always
set to 0 or 3.
Control Methods
Change
Setting Factory during
Range Setting Opera-
V/f
tion
*
1 No Q
0 to 3
MEMO
Open
BUS
V/f Flux
Loop
Regis-
with Vec-
Vec-
ter
PG tor
tor
Q Q Q 492H