Siemens MICROMASTER 420 - Manual (Page 115)

Issue 07/04 3 Functions
MICROMASTER 420 Operating Instructions
6SE6400-5AA00-0BP0 115
3.12.3 OFF/braking functions
Parameter range: P1121, P1135, P2167, P2168
P0840 – P0849
r0052 bit 02
Warnings -
Faults -
Function chart number: -
The drive inverter and the user must respond to an extremely wide range of
situations and stop the drive. In this case, both requirements relating to operations
as well as drive inverter protective functions (e.g. electrical and thermal overload)
and man-machine protective functions have to be taken into account. As a result of
the different OFF/braking functions (OFF1, OFF2, OFF3) MICROMASTER can
flexibly respond to the requirements mentioned above.
OFF1
The OFF1 command is closely coupled to the ON command. When the ON
command is withdrawn, then OFF1 is directly activated. The drive is braked by
OFF1 with the ramp-down time P1121. If the output frequency falls below the
parameter value P2167 and if the time in P2168 has expired, then the inverter
pulses are cancelled.
t
P2168
t
P2167
Operation
act
f
OFF1
P1082
f
max
r0052 Bit02
P1121
P1082
f
P1121 t
2
1 OFF , down
⋅ =
t
down,OFF1
Pulse
cancellation
Fig. 3-44 OFF1
NOTE
OFF1 can be entered using a wide range of command sources via BICO
parameter P0840 (BI: ON/OFF1) and P0842 (BI: ON/OFF1 with reversing).
BICO parameter P0840 is pre-assigned by defining the command source using
P0700.
The ON and the following OFF1 command must have the same source.
If the ON/OFF1 command is set for more than one digital input, then only the
digital input that was last set, is valid, e.g. DIN3 is active.
OFF1 can be combined with DC current braking or compound braking.
When the motor holding brake MHB (P1215) is activated, for an OFF1, P2167
and P2168 are not taken into account.