SCE M68-2000 2-Axis Motion Controller Hardware Version 2.3/B for CNC and Servo Systems

The SCE M68-2000 is a dedicated 2-axis motion controller with hardware revision 2.3/B. It combines PLC logic with CNC interpolation for driving servo or stepper motors. This unit is designed for machine control requiring coordinated moves, such as XY tables, gantry systems, and small routers. Firmware supports G-code execution and multitasking.

Motion Control Specifications

Two axes, each with maximum pulse output frequency of 4 MHz (line driver) or 500 kHz (open collector). Positioning range: ±8,388,607 counts per axis (23-bit signed). Linear, circular, and helical interpolation supported. Acceleration profiles: trapezoidal and S-curve. Electronic gearing and electronic camming functions. Encoder feedback up to 2 MHz for closed-loop servo control.

Hardware Version 2.3/B Features

This hardware revision includes improved isolation on pulse outputs and encoder inputs. Onboard memory: 2 MB flash for part programs, 512 KB for PLC ladder. Real-time clock with lithium battery backup. Communication ports: RS-232 (programming and CNC upload), RS-485 (Modbus RTU master/slave), USB device, and optional Ethernet module (10/100). Digital I/O: 16 opto-isolated inputs (24V DC, 5mA) and 12 transistor outputs (24V DC, 0.5A each, sinking).

CNC and G-Code Support

The controller interprets standard G-code (RS-274D subset) including G00, G01, G02, G03, G04, G17-G19, G90, G91, M03-M08, and M30. Supports up to 2000 program lines, subroutines, and macros (with variables). Tool length compensation and cutter radius compensation are available. The firmware (version as of HW 2.3/B) also supports look-ahead (block processing) up to 200 blocks for smooth high-speed machining.

PLC Logic Capabilities

Built-in ladder logic interpreter with 1000 program steps. Execution cycle time<5 ms per 100 steps. The PLC program can control auxiliary functions (coolant, spindle on/off, tool changer) while motion executes independently. Twin tasks: one for motion, one for logic. I/O mapping allows direct control of outputs based on position events (position switches).

Software and Programming

M68 Studio software (version 3.0 or higher) provides ladder editor, G-code transfer, motion tuning, and real-time scope. Programs can be stored on the controller and started via external run signal. Offline simulation of G-code is available. The RS-232 port supports up to 115200 baud. The USB port acts as a virtual COM port for easy connection.

Electrical and Environmental

Power supply: 24V DC ±10%, 300 mA (plus external load). Operating temperature: 0-55°C. Storage: -20-70°C. Enclosure: Metal case for EMC protection, DIN rail mount (35mm). Dimensions: 150 x 110 x 45 mm. Weight: 0.6 kg. IP20 protection. The controller includes a hardware watchdog timer that disables outputs if program hangs.

Applications

Used in CNC retrofits, automatic soldering machines, coil winders, pick-and-place units, and laser engraving machines. The HW 2.3/B revision is particularly robust for industrial environments with moderate vibration.

Accessories

An optional handheld pendant (MPG) with axis selection and feed override is available. Expansion I/O modules (8 or 16 points) can be added via ribbon cable, up to 64 additional I/O points. A 7-inch touchscreen HMI pre-configured for M68-2000 is offered by SCE.

Compliance

CE, FCC Class A. RoHS compliant. Designed to meet EN 61131-2 for industrial controllers. The controller is not certified for safety-critical applications without external safety relays.

Conclusion

The SCE M68-2000 hardware 2.3/B motion controller delivers precise 2-axis coordination with integrated PLC logic, making it a versatile choice for small CNC and servo-driven machinery.