12.3 Power Supply
To start up your equipment, you will need to select the power supply for the motors.
The
M50PCI
stepping motor card
can be operated on 12 V from your PC power supply by
plugging in the hard disk connector. For motors with a nominal voltage rating higher than
8-10V, be sure to select external power supply. This also applies to positioning systems that
are to be operated at a higher velocity.
To power the card by an external power supply, plug in the two-pole connecting cable
supplied with the card. A power supply source with up to 48V DC maximum can be
connected. The higher the power supply, the higher the attainable velocity and acceleration.
The power supply source should generate an amperage of 1.5-3.0A. We recommend using
the external power supply 40 3222 000 to operate the
M50PCI
stepping motor card
with
LINOS x.act positioners.
You will need to change the position of the high-current jumper on the
M50PCI
stepping motor card
depending on the type of power supply you are using (see
page 28, Factory-Settings: Internal Supply).
Caution: The external power supply may not exceed 48V/DC!
12.4 Electrical Current for the Motors
The electrical current for the motors is set using the software installed (see manual on
support CD
Set_Maximum_Current / Get_Maximum_Current
). The maximum current you
can set for the motors is 2.5 A per phase.
To ensure accurate microstep division, the phase current selected may not be higher than
the nominal current of the motor. By contrast, a current setting that is too low will not affect
microstep division.
When the stepping motors are in an idle state, a much lower torque is generally needed than
when they are driving the positioner. To prevent the motors from losing power or heating up
unnecessarily, the software program lets you define the idle current separately for each axis
(see also
Set_Power_Down
in the manual).
The following example shows how the electrical motor power and power loss are calculated:
Coil
resistance
R
Phase
= 1.6 ohms and
Nominal
current
I
Phase
= 1.5A
Nominal voltage (DC)
V
Phase
= R
Ph
x I
Ph
= 2.4V
The power loss in the switching controllers of the
M50PCI
stepping motor card
play a
subordinate role when the motors are in the idle state.
402310 32 M50.PCI
