ABB ACS560 - Page 184

WARNING!
Do not use a brake resistor with a resistance below the minimum value
specified for the particular drive. The drive and the internal chopper are not
able to handle the overcurrent caused by the low resistance.
Stop time for an application
Stop time is the time required for the load speed to reach zero.
Equation for calculating stop time:
, where,
= stop time in seconds t
on
= load inertia in kgm
2
J
= speed of motor in rpm n
start
= motor stop speed in rpm n
end
= load torque, torque required for the application T
load
For example, if
= 60 kgm
2
J
= 800 NmT
load
= 1000 rpmn
start
= 0n
stop
then stop time,
Example for selecting a brake resistor
If,
= ACS560-01-04A0-4the selected drive
= 1.5kWmotor power
(P
Rmax
)
= 30sstop time (t
on
)
= 180srunning time (T)
then,
184 Resistor braking