Rockwell Automation Allen-Bradley PowerFlex 700 B Series, Руководство пользователя

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C-38 Application Notes
Brake to
Stop
This method uses DC injection of the motor to Stop and/or hold the load.
1. On Stop, 3 phase drive output goes to zero (off)
2. Drive outputs DC voltage on the last used phase at the level programmed in [DC Brake
Level] Par 158. This voltage causes a “stopping” brake torque. If the voltage is applied
for a time that is longer than the actual possible stopping time, the remaining time will
be used to attempt to hold the motor at zero speed.
3. DC voltage to the motor continues for the amount of time programmed in [DC Brake
Time] Par 159. Braking ceases after this time expires.
4. After the DC Braking ceases, no further power is supplied to the motor. The motor may
or may not be stopped. The drive has released control.
5. The motor, if rotating, will coast from its present speed for a time that is dependent on
the mechanics of the system (inertia, friction, etc).
Ramp to
Stop
This method uses drive output reduction to stop the load.
1. On Stop, drive output will decrease according to the programmed pattern from its
present value to zero. The pattern may be linear or squared. The output will decrease
to zero at the rate determined by the programmed [Maximum Freq] and the
programmed active [Decel Time x].
2. The reduction in output can be limited by other drive factors such as such as bus or
current regulation.
3. When the output reaches zero the output is shut off.
4. The motor, if rotating, will coast from its present speed for a time that is dependent on
the mechanics of the system (inertia, friction, etc).
Mode Description
Stop
Command DC Hold Time
(A) (C) (B)
Time
Output Voltage
Output Current
Motor Speed
DC
Hold Level
DC Hold Time
DC
Hold
Level
Stop
Command
Time
Output Voltage
Output Current
Motor Speed
Output Voltage
Output Current
Zero
Command
Speed