Electronic Brakes; Dc Braking - Siemens MICROMASTER 420 Operating Instructions Manual

3 Functions
3.14

Electronic brakes

MICROMASTER 420 has 2 electronic brakes:

DC braking

Compound braking
These brakes can actively brake the drive and avoid a possible DC link overvoltage
condition. An inter-dependency as shown in Fig. 3-50 is present.
Fig. 3-50
3.14.1 DC braking
Parameter range:
Warnings
Faults
Function chart number:
The drive decelerates along a parameterized braking ramp if an OFF1 / OFF3
command is output. A "flat" ramp must be selected so that the drive inverter is not
tripped (shutdown) due to the high regenerative energy which would cause a DC
link overvoltage condition. The DC brake should be activated while the OFF1 /
OFF3 command is present if the drive is to be braked faster. For DC braking,
instead of continually reducing the output frequency / voltage during the OFF1 /
OFF3 phase, a DC voltage / current is input (refer to sequence a).
The drive can be brought to a standstill in the shortest time using DC current
braking (DC brake). DC braking is selected as follows:
After OFF1 or OFF3 (the DC brake is released via P1233)
Directly selected using BICO parameter P1230
For DC braking, a DC current is impressed in the stator winding which results in a
significant braking torque for an induction motor. The magnitude, duration and
frequency at which braking starts can be set for the braking current and therefore
braking torque by setting the appropriate parameters.
122
(refer to Section 3.14.1)
(refer to Section 3.14.2)
DC braking
no
P1233 > 0
?
yes
DC braking Compound braking
enabled
Inter-dependency of the electronic brakes
P1230, P1232, P1233
r0053 Bit00
-
-
-
Compound
no
braking
P1236 > 0
?
yes
enabled
MICROMASTER 420
Issue 07/04
disabled
Sequence
Sequence
Operating Instructions
6SE6400-5AA00-0BP0