
24
Service Manual
Plus
MICROSPEED
3.2 Power Supply Construction and Rating
Installation
WARNING:Use only Un-regulated power supplies with the
Microspeed Plus Drive.The power supply is used to
absorb the motor's BEMF. Als, with this scheme, no
braking resistor are needed.
The MicrospeedPlus was designed to generate all required
supply voltages in the Drive, so only a simple single voltage power
supply is needed. Use the schematic and formulas provided
below to design a supply that will be trouble-free and handle the
power needed by the drive.
Transformer:
A single ground is used in the drive that is
connected to -AT, so
DO NOT USE AN AUTO
TRANSFORMER
. Use a standard heavy duty power transformer
without center taps on the secondary as shown in the schematic
above. The VA rating should be 10% greater than the power
needed by the system to insure cool operation.
DO NOT
CONNECT ANY TRANSFORMER PRIMARY, OR
SECONDARY SIGNALS TO GROUND.
Keep the +AT and -AT wires, between the power supply and the
Microspeed Plus, as short as possible.