Posted to News on 30th Jan 2008, 20:37
Stepper drives come with a choice of built-in intelligence
Mclennan Servo Supplies is launching a new range of 5 and 10A intelligent stepper drives from the California-based motion control company Applied Motion Products. The new ST series microstepping drives are available in three competitively priced versions, offering a wide choice of control options that include step and direction input, encoder following, graphical point-and-click programming for simple machine sequencing, and high-level ASCII host control for complex multi-axis motion and machine control.
The ST series drive stage features 20kHz PWM current control and is available in a choice of user supplied 24-48V DC at 5.0A peak or 24-80V DC at 10.0A peak. The fully protected drive features advanced current control to reduce motor torque ripple and smooth the output command signal to soften sudden changes in velocity and direction - which helps to reduce wear on mechanical components. The drive stage also features an anti-resonance damping term that improves the stability performance of the motor, allowing higher speeds and more usable torque.
Three control options are available - ST-S, ST-Si and ST-Q - allow a cost-effective choice of motion and machine interfacing. The entry-level ST-S version handles step and direction, CW/CCW pulse, master encoder following and a basic level of host control using Applied Motion Products' SCL programming language.
The mid range ST-Si (Simple Indexer) version provides standalone operation using Applied Motion Products' Windows-based Si Programmer graphical software. This point-and-click package utilises a highly user-friendly icon-based programming environment that allows users of all levels to quickly set-up and program standalone machine sequencing applications, interfacing the controller with sensors, PLCs, HMIs and other machine controls. The controller covers motion commands, I/O, conditional branching, alarms and operator interfacing, and also provides comprehensive troubleshooting support. The ST-Si controller option also enables real time host control and handles program uploading and downloading.
On-the-fly functions
For more sophisticated applications, the ST-Q controller version uses Motion Control Products' high-level Q programming language to write sequences of complex multi-tasked motion and machine control. With full on-the-fly functionality, the ST-Q intelligent drive can handle electronic gearbox and registration functions. With the addition of an encoder, the ST-Q series drive can provide stall detection and prevention - thereby ensuring the motor will attempt to finish its move under stall conditions. Encoder-based position maintenance is also available to return a motor to its commanded position if external forces try to force it away.
Each ST drive version includes selectable microstepping resolution up to 50,800 steps/rev. At start-up, a self-test and auto-setup routine measures actual motor parameters to ensure optimal performance and fault-free operation. Each controller version carries an increasing generous complement of user I/O, along and communications interfacing - for instance, the ST-Q includes two high-speed inputs, six general-purpose inputs, two analogue inputs and four digital outputs.
Applied Motion Products' ST Configurator software is also available for setting up, configuring, uploading and downloading programs to the ST series drives.
Multi-axis system setups, using PC Host control via RS 485/422, is available for the Si and Q versions. Multi-axis host control or standalone control is also possible with the SiNET Hub, which allows up to four or eight ST-S, ST-Q, or ST-Si drives to be configured, programmed and then networked with a PC, PLC or HMI in host or standalone modes.
The Applied Motion Products range also covers intelligent servo drives that utilise the Si and Q programming environments.
