User Manual Instruction Manual

Application Notes 13-37
A “Ramp” selection will always provide the fastest stopping time if a method to
dissipate the required energy from the DC bus is provided (i.e. resistor brake,
regenerative brake, etc.). The alternative braking methods to external brake
requirements can be enabled if the stopping time is not as restrictive. Each of these
methods will dissipate energy in the motor (use care to avoid motor overheating).
Table 13-1 describes several braking capability examples.
Table 13.1 – Braking Method Examples
Method Use When Application Requires . . . Braking Power
Ramp The fastest stopping time or fastest ramp
time for speed changes (external brake
resistor or regenerative capability required
for ramp times faster than the methods
below).
High duty cycles, frequent stops or speed
changes. (The other methods may result in
excessive motor heating).
Most
Fast Brake Additional braking capability without use of
external brake resistor or regenerative units.
More than
Flux Braking
or DC Brake
Flux Braking Fast speed changes and fast stopping time.
Typical stop from speeds below 50% of
base speed (“Flux Braking” will likely stop
the load faster than “Fast Brake” in this
case)
Important: This can be used in conjunction
with “Ramp” or “Ramp to Hold” for additional
braking power or with “Fast Brake” or “DC
Brake” for speed changes.
More than DC
Brake
DC Brake Additional braking capability without use of
external brake resistor or regenerative units
Less than
above
methods
Mode Description
Coast to Stop
This method releases the motor and allows the load to stop by
friction.
On Stop, the drive output goes immediately to zero (off).
No further power is supplied to the motor. The drive has released
control.
The motor will coast for a time that is dependent on the mechanics of
the system (inertia, friction, etc).
Coast Time is load dependent
Stop
Command
Time
Output Voltage
Output Current
Motor Speed