Yaskawa Sigma II Series Servo System - Manual (Page 177)

Sigma II User’s Manual Chapter 5: Parameter Settings and Functions
5-91
If the previous calculation determines that the amount of regenerative power (W
Wk.
)
that can be processed by the built-in resistor is not exceeded, then an external
regenerative resistor is not required.
If the amount of regenerative power that can be processed by the built-in resistor is
exceeded, install an external regenerative resistor for the capacity obtained from the
above calculation.
If the energy consumed by load system loss (in step 2 above) is unknown, then
perform the calculation using E
L
= 0.
When the operation period in regeneration mode is continuous, add the following
items to the above calculation procedure in order to find the required capacity (W)
for the regenerative resistor.
• Energy for continuous regeneration mode operation period: E
G
(joules)
• Energy consumed by regenerative resistor: E
K =
E
S
- (E
L
+ E
M
+ E
C
) + E
G
• Required capacity of regenerative resistor: W
K
= E
K
/ (0.2 × T)
Here, E
G
= (2 π /60) N
MG
× τ
G
× t
G
• τ
G
: Servomotor’s generated torque [oz-in (N-m)] in continuous regeneration
mode operation period.
• N
MG
: Servomotor rotation speed (rpm) for same operation period as above.
• t
G
: Same operation period (s) as above.