Shihlin electric SDP Series, Manual

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Note 1: Es is the regenerated energy of a motor without loading that runs a rated speed then
stops.
The capacity of regenerative resistor is calculated as follows by using the Es and Ec in the
above table:
In which N: the Load inertia ratio T: operation cycle(Defined by user)
Assuming that the load inertia is N times the motor inertia, when the motor decelerates from
3000rpm to 0, the regenerative energy is (N+1)×Es and the regenerative resistor needs to
consume (N+1) × Es-Ec Joules. Assuming that the operation cycle is T sec, then the required
regenerative resistor power =2×((N+1) × Es
－
Ec) / T . the calculation is as follows
；
Note: J: motor inertia(unit: kg
‧
m
2
), Wr: maximum speed of operation cycle(unit: rpm)
Step Item Calculation and instruction
1 Set the operation cycle T Manual input(operation cycle)
2 Set rotation speed Wr Manual input or read from panel status display(r)
3 Set load / motor inertia ratio N Manual input or read from panel status display(Dc)
( PA01=0002 is valid)
4 Calculate the maximum
regenerative energy Es Es = J * Wr
2
/ 182 ( if it’s rated speed, you can
check the value in the table directly)
5 Set the consumable
regenerative energy Ec Refer to the above table
6 Calculate the capacity of
regenerative resistor 2 * ((N + 1) * Es - Ec) / T
Example 1
Taking the low inertia 400W model as an example, the operation cycle T = 1 sec, the
maximum speed is 3000rpm, and the load inertia is 20 times of the motor inertia, then the
required power of the regenerative resistor = 2 x ((20 + 1) x1.37 -9.9 ) / 1 = 37.7W. Therefore,
an external regenerative resistor above 37.7w is required.
Note: since the maximum speed of 3000rpm is rated speed of 400W motor, it can be found
from the above table that Es =1.37 J.
Example 2
Taking the middle inertia 2KW model as an example, the operation cycle T = 1 sec, the