C.9. connecting regenerative resistors, Servo amplifiers with capacity of 400 w or less – Yaskawa FSP Amplifier User Manual
Page 340

FSP Amplifier User’s Manual
Appendix C: Specifications for Peripheral Devices
C-9
C.9. Connecting Regenerative Resistors
The method for connecting regenerative resistors is shown below. See Appendix
E for the external regenerative resistor specifications.
Disconnect the wire between the FSP Amplifier’s B2 and B3 terminals and
connect an external regenerative resistor between the B1 and B2 terminals.
Regenerative resistor
B1
B2
FSP Amplifier
*The user must provide the regenerative resistor.
B3
Be sure to take out the lead wire
between the B2 and B3 terminals.
Calculating the Regenerative Power Capacity
Simple Calculation Method
When driving a servomotor normally along the horizontal axis, check the
external regenerative resistor requirements using the calculation method
shown below.
Servo Amplifiers with Capacity of 400 W or Less
Servo amplifiers with a capacity of 400 W or less do not have built-in
regenerative resistors. The energy that can be absorbed by capacitors is
shown in the following table. If the rotational energy in the servo system
exceeds these values, then connect a regenerative resistor externally.
Voltage
Applicable Servo
Amplifiers
FSP-
Regenerative Energy
that Can be Processed
(joules)
Comments
A3B* 7.8
100 V
A5B* to 02B*
15.7
Value when the input voltage
is 100 VAC
A3A* and A5A*
18.5
200 V
01A* to 04A*
37.1
Value when the input voltage
is 200 VAC
Calculate the rotational energy in the servo system using the following
equation:
E
S
=
( )
12566
N
x
J
2
M
Joules
Where: J = J
M
+ J
L
J
M
: Servomotor rotor inertia (kg·m
2
) (oz·in·s
2
)
J
L
: Motor axis conversion load inertia (kg·m
2
) (oz·in·s
2
)
N
M
: Rotation speed of the servomotor (rpm)