Regeneration Resistor Selection; Required Information - Baldor MotiFlex e100 Installation Manual

3.9 Regeneration resistor selection

The following calculations can be used to estimate the type of regeneration resistor that will be
required for the application.

3.9.1 Required information

To complete the calculation, some basic information is required. Remember to use the worst-case
figures to ensure that the regeneration power is not underestimated. For example, use the
maximum possible motor speed, maximum inertia, minimum deceleration time and minimum
cycle time that the application might encounter.
Requirement
a) Initial motor speed, before deceleration
begins, in radians per second.
Multiply RPM by 0.1047 to give radians
per second.
b) Final motor speed after deceleration is
complete, in radians per second.
Multiply RPM by 0.1047 to get radians
per second. This value will be zero if the
load is going to be stopped.
c) The deceleration time from initial speed
to final speed, in seconds.
See section 3.9.7.
d) The total cycle time (i.e. how frequently
the process is repeated), in seconds.
See section 3.9.7.
e) Total inertia.
This is the total inertia seen by the drive,
accounting for motor inertia, load inertia
and gearing. Use the Mint WorkBench
Autotune tool to tune the motor, with the
load attached, to determine the value.
This will be displayed in kg·m
Autotune tool. If you already know the
motor inertia (from the motor spec.) and
the load inertia (by calculation) insert the
total here.
Multiply kg·cm
Multiply lb-ft
Multiply lb-in-s
3-38 Basic Installation
2
in the
2
by 0.0001 to give kg·m
2
by 0.04214 to give kg·m
2
by 0.113 to give kg·m
Enter value here
Initial motor speed, U = _________ rad/s
Final motor speed, V = _________ rad/s
Decel time, D
Cycle time, C
Total inertia, J
2 .
2 .
.
2
www.baldormotion.com
= _________ s
= _________ s
2
= ________ kg·m
MN1943