Commissioning
5–25
1070 066 028-101 (01.05) GB
5.1.17
D.C. link control in the event of a power failure
If no line voltage is present, the frequency inverter maintains the d.c. link by
using the kinetic motor energy, thus providing for safe braking up to motor
zero speed. The time required for braking only depends on the external mo-
ment of inertia.
D
Power failure, power interruption or EMERGENCY-STOP
The braking operation starts as soon as the voltage drops below the un-
dervoltage limit. If the line power returns during the braking phase, the
inverter accelerates in a controlled restart operation in accordance with
the acceleration ramp setting.
D
Braking with setpoint control
The braking operation starts when the d.c. link voltage exceeds 700 V.
Depending on the external moment of inertia, the inverter extends the
braking ramp selected in P12 and maintains the d.c. link voltage at 700 V.
P47 (A-0-0047)
D.C. link control in the event of a power failure
factory
setting for ASM
all
DMs, DS
bc0
(0)
bc2
(2)
Off
On,
power failure
and EMER-
GENCY-STOP
On,
setpoint-con-
trolled braking
bc3
(3)
On,
power failure,
EMERGENCY-
STOP
and braking
bc1
(1)