User`s manual

146 • Vacon apfiff09 marine
Tel. +358
6
P2.6.5.3 Brake chopper ID504
When the AC drive is decelerating the motor, the inertia of the motor and the load are fed
into an external brake resistor. This enables the drive to decelerate the load with a
torque equal to that of acceleration (provided that the correct brake resistor has been
selected). See separate Brake resistor installation manual. Brake chopper test mode
generates pulse to resistor every second. If the pulse feedback is wrong (resistor or
chopper is missing) fault F12 is generated.
0 = - No brake chopper used
Brake chopper not active or present in the DC link. NOTE: The overvoltage
controller level is set to a little lower, see parameter P2.6.5.2.
1 = - Brake chopper in use and tested when running.
The drive own brake chopper is activated and operational when the drive is in
Run state. The drive also sends test pulses for feedback from the brake resistor.
2 = - External brake chopper (no testing)
The system has an item that handles the DC link voltage. This could be a system
with AFE or there is an external BCU unit. When this option is selected the drive
overvoltage level is set a little higher so that its operation does not conflict with
AFE or BCU units.
3 = - Used and tested in READY state and when running
Brake chopper is also active when the drive is not in Run state. This option can be
use e.g. when other drives are generating but energy levels are low enough to be
handled with only one drive.
4 = - Used when running (no testing)
Brake chopper is active in Run state but no test pulse to resistor is generated.
Note: In the system menu there is . This parameter is
used for brake resistor overheating calculations. If an external brake resistor is
connected to the drive the parameter should be set to ot connected to disable
temperature calculation for the brake resistor.
P2.6.5.4 Brake Chopper Level ID1267
Brake chopper control activation level in volt. This parameter is active when
For 400V Supply: 400*1.35*1.18 = 638V
For 500V Supply: 500*1.35*1.18 = 808V
For 690V Supply: 690*1.35*1.18 = 1100V
Over Voltage Reference Select
Brake chopper level
0 /High voltage
500 V Unit: 797 V
690 V Unit: 1099 V
1 / Norm.Voltage
1.18* Estimated DC nominal voltage
2 / BrakeChLevel
Brake chopper level