Intelligent Motion Systems MFM Motion Detector, Operating Instructions Manual

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Microstepping MForce PowerDrive Manual Revision R032008
The per phase winding inductance specified may be different than the per phase inductance seen by your MForce
PowerDrive driver depending on the wiring configuration used. Your calculations must allow for the actual induc-
tance that the driver will see based upon the wiring configuration.
Figure 2.3.1A shows a stepper motor in a series configuration. In this configuration, the per phase inductance
will be 4 times that specified. For example: a stepping motor has a specified per phase inductance of 1.47mH. In
this configuration the driver will see 5.88 mH per phase.
Figure 2.3.1B shows an 8 lead motor wired in parallel. Using this configuration the per phase inductance seen by
the driver will be as specified.
Using the following equation we will show an example of sizing a motor for a MForce PowerDrive used with an
unregulated power supply with a minimum voltage (+V) of 18 VDC:
.2 X 18 = 3.6 mH
The recommended per phase winding inductance we can use is 3.6 mH.
Recommended IMS Motors
IMS also carries a series of 23 and 34 frame enhanced stepping motors that are recommended for use with the MForce
PowerDrive. These motors use a unique relationship between the rotor and stator to generate more torque per frame
size while ensuring more precise positioning and increased accuracy.
The special design allows the motors to provide higher torque than standard stepping motors while maintaining a
steadier torque and reducing torque drop-off.
Each frame size is available in 3 stack sizes, single or double shaft, with or without encoders. They handle currents up
to 2.4 Amps in series or 6 Amps parallel, and holding torque ranges from 90 oz.-in. (M-2218-2.4) to 1303 oz.-in (M-
3447-6.3) (64 N-cm to 920 N-cm).
These CE rated motors are ideal for applications where higher torque is required.
For more detailed information on these motors, please see the IMS Full Line catalog or the IMS web site at
http://www.imshome.com.
PHASE A
PHASE A
PHASE B
PHASE B
8 Lead Stepping Motor
Series Configuration
8 Lead Stepping Motor
Parallel Configuration
PHASE A
PHASE A
PHASE B
PHASE B
(Note: This exampl e a lso
applies to the 6 lead motor
full copper configuration and
to 4 lead stepping motors)
(Note: This exampl e a lso
applies to the 6 lead motor
half copper configuration)
Specified Per Phase
Inductance
Specified Per Phase
Inductance
Actual Inductance
Seen By the Driver
Actual Inductance
Seen By the Driver
A B
Figure 2.3.1 A & B: Per Phase Winding Inductance
Maximum Motor Inductance (mH per Phase) =
.2 X Minimum Supply Voltage
NOTE: In
calculating the
maximum phase
inductance, the
minimum supply output
voltage should be used when
using an unregulated supply.