4.1.2.5 Contactors behind the power supply
SOMANET servo drives are designed for voltages between 12 V and 48 V (60 V Max). Please do not use
contactors behind the power supply since the transient-voltage-suppression diodes could get damaged due to
the power-up voltage increase (Surge). This is likely to happen when the power-up occurs fast.
This can lead to complete failure of the servo drive.
It is recommended to use a 48 V DC power supply that is common in many industries. A power supply with a
significant capacity is required for a servo drive application. Up to 55 V is tolerable for a long time and up to 60
V is acceptable for a time shorter than 1 second. This would allow for regenerative braking of any robot arm,
but might be dangerous in systems where gravity provides regenerative power over a longer time, for example
in lifting systems or AGVs.
Regenerative currents can occur depending on the commanded trajectory. If the power supply cannot
withstand such currents, a braking chopper system must be used additionally.