Siemens MICROMASTER 440 - Manual (Page 60)

6 Commissioning Issue 10/06
MICROMASTER 440
60 Operating Instructions (Compact)
6.4.18.6 Dynamic braking
The following settings should always be made:
¾
The Vdc_max controller de-activated P1240 = 0 (def.: P1240 = 1)
¾ The compound brake de-activated P1236 = 0 (def.: P1236 = 0)
¾ Resistor brake activated P1237 > 0 (def.: P1237 = 0)
Dynamic braking
Dynamic braking is activated using parameter P1237 – the nominal (rated) duty cycle as
well as the switch-in duration of the braking resistor are also defined.
0 Inhibited
1 Load duty cycle 5 %
2 Load duty cycle 10 %
3 Load duty cycle 20 %
4 Load duty cycle 50 %
5 Load duty cycle 100 %
Using the dynamic brake, the regenerative feedback energy is transferred to the external
braking resistor using the chopper control (braking chopper); it is converted into thermal
energy (heat) in this resistor. This dynamic braking allows the drive to be braked in a
controlled fashion. This function is not available for sizes FX and GX.
Chopper resistor
Chopper
control
B-
=
~
~
B+
=
~
MM4
6.4.18.7 Vdc controller
Configuration of Vdc controller
Enables / disables Vdc controller.
0 Vdc controller disabled
1 Vdc-max controller enabled
P1254 =... Auto detect Vdc switch-on levels
Enables/disables auto-detection of switch-on
levels for Vdc control functionalities.
0 Disabled
1 Enabled
t
t
⏐f⏐
1
-controller active V
DC_max
t
V
DC
0
r0056 Bit14
r1242
A0911
f
f
act
set
P1237 = ...
0
1
1
P1240 =...