Micro-PLC can handle small standalone machines
Rockwell Automation has announced a micro-PLC for small standalone machines and remote automation projects, such as stretch wrappers and compressors. The 20-point Allen-Bradley Micro820 PLC has embedded Ethernet and serial ports, a micro-SD memory slot, a 5kHz PWM (pulse-width modulation) output, analogue and four thermistor inputs, and recipe management functions.
“We will continue to develop the Micro800 platform to give small-machine builders the flexibility to customise designs according to their application needs,” says Melkote Srinivasan, senior business manager at Rockwell. “The new Micro820 controller, LCD display, plug-in modules and Connected Components Workbench software Release 6.0 have the features and options that help them differentiate their offerings and be more competitive.”
An optional 3.5-inch LCD provides up to eight lines of text with a four-colour backlight. The IP65-protected display has a keypad with programmable function keys, and can be mounted through a cabinet door for use as an operator interface. The display shows customised application-diagnostics messages and text. Machine-builders can use the LCD to view and edit program variables, and to set the controller’s Ethernet address.
A plug-in DeviceNet scanner option supports up to 20 nodes of PowerFlex AC drives or CompactBlock LDX I/O. This cuts the costs of wiring and installation inside the cabinet for standalone machine applications, and outside the cabinet for conveyor applications with drives and I/O distributed over long distances. Auto-scan and device-specific function blocks simplify programming, configuration, and network diagnostics.
Another option is a high-speed counter plug-in module which allows machine-builders to add high-speed counters to the controllers. When used with a PTO axis, the module provides position feedback from a servodrive for position verification or with an encoder for position and velocity monitoring. It supports both 5V differential line driver input up to 250kHz, and 24V DC input up to 100kHz.
The Connected Components Workbench software simplifies the configuration, design and maintenance of the Micro820 controller. The latest version of the software adds support for more machine devices, such as the new Allen-Bradley Guardmaster 440C-CR30 configurable safety relay and Allen-Bradley Kinetix 3 component servodrive. The software is a free download and offers built-in tutorials, manuals and user assistance.