Lenze 8400 StateLine - Manual (Page 229)

Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14
229
5 Motor control (MCTRL)
5.11 Braking operation/brake energy management
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5.11.1 Setting the voltage source for braking operation
The voltage threshold for braking operation is set via the mains voltage ( C00173 ) and the reduced
brake chopper threshold ( C00174 ). When this "brake chopper threshold" is exceeded, the response
selected in C00175 takes place in the DC bus. The selected function (e.g. use of a brake resistor)
serves to dissipate energy in the DC bus and reduce the DC-bus voltage.
• The "brake chopper threshold" is preset as follows so that it is higher than the specified mains
voltage ( C00173 ):
• This brake chopper threshold can be reduced by 0 ... 150 V by means of C00174 .
Example:
• A 400 V device has a maximum mains voltage of 420 V AC.
• Maximum stationary DC-bus voltage: 420 V AC * 1.414 = 594 V DC
•
C00173 has been set with the selection "0" for 400 V AC mains.
• This means that C00174 can be set to a maximum of 131 V DC (725 V DC - 594 V DC).
5.11.2 Selecting the response to an increase of the DC-bus voltage
If the brake chopper threshold resulting from C00173 and C00174 is exceeded in the DC bus, the
reaction selected in C00175 takes place (use of the brake resistor and/or stop of the ramp function
generator and/or inverter-motor brake).
• Optimum following of the actual speed value until the speed setpoint is reached (e.g. the motor
is stopped rapidly) is always achieved with the help of a brake resistor.
• Stopping the ramp function generator enables smoother deceleration with lower torque
oscillation..
• The inverter motor brake is available in C00175 from version 04.00.00 onwards . This function
enables rapid braking without a brake resistor. Torque oscillations can occur due to the
traversing dynamics.  Inverter motor brake ( 231)
Mains voltage Brake chopper threshold
C00173 1-phase 3-phase 1-phase 3-phase
0 1ph 230V 3ph 400V DC380V DC725V
1 1ph 230V 3ph 440V DC380V DC735V
2 1ph 230V 3ph 480V DC380V DC775V
3 1ph 230V 3ph 500V DC380V DC790V

Stop!
The brake chopper threshold resulting from C00173 and C00174 must not exceed the
stabilised DC-bus voltage!