The difference between the success and failure of your control system design is largely dependent on the flexibility of the controller you choose, particularly in the micro PLC class, where many of the controllers in this class only can be configured to communicate with one device at a time.
IDEC says its new MicroSmart Pentra PLC solves that problem by allowing up to 14 connections at the same time.
"With a built-in Ethernet port, these new PLCs can be configured by a DHCP server so the PLC will automatically obtain the IP address once connected to the network via special data registers or with a static IP address," says Britt Davis, automation sales manager at IDEC. "Up to 14 connections can be configured to simultaneously communicate with your PC using a standard web browser through a TCP/IP connection, WindLDR software for maintenance communication, SCADA supervisory controls, Modbus TCP Client and Modbus TCP Server, all at the same time. You can monitor status in real time, receive instant email/text alerts, and customize your own web page. A PING function also allows the PLC to initiate and check communication with other devices on the network."
A standard web browser such as Internet Explorer or Firefox provides remote log-in and access to web pages stored directly on the PLC. "Use a built-in IDEC web page to remotely monitor and control parameters in the MicroSmart Pentra or create your own custom web page," Davis says. "Up to 1 MB of memory is reserved just for web page creation. Novice HTML programmers can use the built-in system library of numerical displays, vertical and horizontal bar graphs, X-Y trend charts, pushbuttons and pilot lights. You don’t have to be a programming expert to create a web page."
MicroSmart Pentra with Ethernet also enables key personnel to receive instant emails and text alerts. "Beyond static messages, dynamic data such as temperature, tank level, pressure, flow rate, time and date, etc. can be incorporated in the body," explains Elias Elters, automation sales manager at IDEC. "Up to 255 emails can be configured. The micro PLC also supports email log-in authentication and the ability to restrict access by IP addresses for added security."
There are four high-speed inputs with a maximum frequency of 100 kHz, and the PLCs support single/dual-phase inputs for rotary encoders, 32-bit counting range up to 4,294,967,295 pulses, integrated functions, executable interrupt programs, frequency measurement, high-speed counter refresh and multi-stage comparison. "Configure as many as three high-speed pulse outputs, up to 100 kHz, and get the simple control you want for stepper or servo motors," Elters adds.
IDEC says its new MicroSmart Pentra PLC family provides the needed edge in performance as well. "These microcontrollers combine advanced networking capabilities with power, performance and connectivity," says Mike Suzuki, product marketing manager at IDEC. "Designed to meet all communication requirements, now and in the future, MicroSmart Pentra PLCs give users the flexibility to expand their system, while providing faster scan times and better throughput."
The new PLC with Ethernet supports up to 128 KB programming memory or 21,300 ladder steps of programming, Suzuki says, more than any other micro PLC in the market. A USB maintenance communication port is included to provide faster and easier communication than a traditional serial port.
These new PLCs meet the highest standards for safety, including cULus listing for Class I, Div. 2 hazardous locations (pending), and are also CE-compliant.