Yaskawa SGDH Linear Sigma Series - Manual (Page 203)

7.6 Connecting Regenerative Resistors
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7.6 Connecting Regenerative Resistors
7.6.1 Regenerative Power and Regenerative Resistance
The kinetic energy of driven machine such as linear servomotor is returned to the SERVOPACK. This is called
regenerative power. The regenerative power is absorbed by charging the smoothing capacitor, but when the
power exceeds the capacitor’s chargeable energy, the regenerative power is further consumed by the regenerative
resistor.
The servomotor is driven in regeneration state in the following circumstances:
• While decelerating to a stop during acceleration and deceleration operation.
• Continuous falling operation on the vertical axis.
• During continuous operation with the servomotor moved from the load side (negative load).
The SERVOPACKs with a capacity of the single-phase 200 V with 50 to 400 W do not have built-in regenerative
resistors. If the value calculated in 12.2 Calculating the Required Capacity of Regenerative Resistors needs an
external regenerative resistor, connect an external regenerative resistor.
7.6.2 Connecting External Regenerative Resistors
(1) Necessity of External Regenerative Resistors
SERVOPACK
Capacity
Necessity of
External Regen-
erative Resistors
Description
400 W or less Not Required No built-in regenerative resistor is provided, however, normally an external
regenerative resistor is not required.
Install external regenerative resistors when the smoothing capacitor in SER-
VOPACK cannot process all the regenerative power.
500 W to 5.0 kW Not Required A built-in regenerative resistor is provided as standard. Install external regen-
erative resistors when the built-in regenerative resistor cannot process all the
regenerative power.
7.5 kW Required No built-in regenerative resistor is provided, so the external regenerative
resistor is required. If the external regenerative resistor is not connected with
the SERVOPACK, the alarm A.30 is detected as a regeneration error alarm.