Copley Controls: Stepnet Micro Module (STL-075 Series)
20-75 VDC & 115-230 VAC Digital Drives for Stepper Motors
Stepnet Micro Module is a stepper motor driver in a 4in2 pc-board mounting package that combines CANopen networking with 100% digital control of stepper motors. Power output is compatible with most NEMA 17 and 23 size stepper motors. The small footprint is well-suited for desktop instrumentation and enables motor drive, interface, power supply, and control circuits to be combined on a single PC board.
Stepnet Micro Module can also operate as a stand-alone driver taking incremental position commands from stepmotor controllers in Step/Direction or CU/CD format, as well as A/B quadrature commands from a master-encoder. Step to motor position ratio is programmable for electronic gearing.
When fitted with an incremental encoder a stepper motor can be operated as a brushless servo motor using Stepnet Micro Module’s Servo Mode feature, or as a conventional stepper with stall detection. Setup is fast and simple using CME 2™ software operating under Windows® and communicating with Stepnet Micro Module via an RS-232 link. CAN address selection is by digital inputs or can be programmed into driver flash memory.
As a CANopen node Stepnet Micro Module operates as a Motion Control Device under the DSP-402 protocol of the CANopen DS-301 V4.01 (EN 50325-4) application layer. DSP-402 modes supported include: Profile Position, Profile Velocity, Interpolated Position (PVT), and Homing. When in Servo Mode, operating the stepper as a servo motor with encoder feedback, Profile Torque mode is available.
Profile Position Mode does a complete motion index on command with S-curve acceleration & deceleration, top speed, and distance programmable. In PVT mode, the controller sends out a sequence of points each of which is an increment of a larger, more complex move than that of a single index or profile. Profile Velocity mode has acceleration, deceleration, and velocity control without a position set point. Homing mode is configurable to work with a combination of limit and home switches such that the driver moves the motor into a position that has an absolute reference to some part of the machine.
One logic input [IN1] is dedicated for the driver Enable function. The other eleven are programmable as CAN address, limit & home switches, stepper pulse inputs, A/B master encoder, motor feedback encoder, reset, motion abort, or motor-temperature. There are four programmable logic outputs for reporting a driver fault, or other status indications. When operating as a CAN node, inputs and outputs can be used as general-purpose I/O with no link to amplifier functions.
An Aux HV input is provided for “keep alive” power that preserves the driver data (e.g. current position) and CANopen operation if +HV has been removed as in an emergency-stop situation. This enables the control system to monitor drive status and to enable an orderly recovery without a full system reset, and “homing” of all axes. Operation from transformer-isolated DC power supplies saves cost in multi-axis systems.
Indexer, Point-to-Point, PVT
Camming, Gearing
Position, Velocity, Torque [Servo Mode]
Position (Microstepping)