17
Service Manual
www.microphase.eu
Dc
Transformer
VDC = V2 * 1,41
Example: If the secondary transformer V2 is 45Vac, the VDC output is 45*1,41=64Vdc
PAY ATTENTION:
- The drive has zero signal GND in conjunction with the zero power GND, thereby preventing the
following links:
- Use a standard heavy duty power transformer without center taps on the secondary as shown in the
schematic above.
-
DO NOT USE AN AUTO TRANSFORMER.
Power transformer (T)
F1
V1
V2
AC
AC
VDC
F2
+HV
(T) TRANSFORMER
GND
C
+
-
AC
POWER
INPUT
3.0
Power supply construction
Normally the power supply is built by a transformer, a bridge rectifier and a filter capacity. Alternatively,
the power supply can also be of switching type, in this case refer factory by the appropriate sizing.
The converter have to be supplied from an isolating rectified transformer secondary or a DC isolated
power supply.
Voltage:
The primary voltage depends on what is available locally for a single phase. The secondary voltage is
calculated from the motor’s voltage at the required operating speed.
The secondary voltage VDC is:
The transformer's nominal power is calculated based upon the sum of power from the single motors
driven:
Where: Pn Motor =
Power absorbed motor
in (W)
N
= Max. speed of motor in RPM.
Cn
= Nominal torque of motor in (Nm).
Pn Motor = N * Cn / 9,55
P(VA)=Pn1+Pn2+..
VDC = Vdc motor / 0,83
Vdc motor = E+(Ri * In)
E = Ke * N° / 1000
Where the Vdc motor is a sum of FCEM + the drop R*I for the winding resistance motor
The FCEM of the motor "E", may be calculated by the formula:
Note: In multi-axis applications, the transformer's power can be downgraded by 30%. If the max.
power transformer calculated is over 6KVA contact the factory.
If the secondary voltage of power supply is VDC, the Vdc motor is calculated by the formula:
Voltage motor
