9
Rev. 1.0
0006302011
SSM23C User Manual
+86-400-820-9661
2.3 Choosing a Power Supply
The main considerations when choosing a power supply are the voltage and current requirements
for the application.
2.3.1 Voltage
The SSM23C is designed to give optimum performance between 24 and 48 Volts DC. Choosing
the voltage depends on the performance needed and motor/drive heating that is acceptable and/
or does not cause a drive over-temperature. Higher voltages will give higher speed performance
but will cause the SSM23C to produce higher temperatures. Using power supplies with voltage
outputs that are near the drive maximum may signifi cantly reduce the operational duty-cycle.
The extended range of operation can be as low as 10 VDC minimum to as high as 75 VDC
maximum. When operating below 18 VDC, the power supply input may require larger capacitance
to prevent under-voltage and internal-supply alarms. Current spikes may make supply readings
erratic. The supply input cannot go below 10 VDC for reliable operation. Absolute minimum power
supply input is 10 VDC. If the Input supply drops below 10 VDC the low voltage alarm will be
triggered. This will not fault the drive.
Absolute maximum power supply input is 75 VDC at which point an over-voltage alarm and fault
will occur. When using a power supply that is regulated and is near the drive maximum voltage
of 75 VDC, a voltage clamp may be required to prevent over-voltage when regeneration occurs.
When using an unregulated power supply, make sure the no-load voltage of the supply does not
exceed the drive’s maximum input voltage of 75 VDC.
2.3.2 Regeneration Clamp
If a regulated power supply is being used, there may be a problem with regeneration. When a
load decelerates rapidly from a high speed, some of the kinetic energy of the load is transferred
back to the power supply, possibly tripping the over-voltage protection of a regulated power
supply, causing it to shut down. This problem can be solved with the use of a MOONS’ RC880
Regeneration Clamp. It is recommended that an RC880 initially be installed in an application. If
the “regen” LED on the RC880 never fl ashes, the clamp is not necessary.
RC880 Regen Clamp
LEDs
Green - Power
Red - Regen on
