One of South Africa's largest local developers and manufacturers of industrial electronics, Omniflex, has released the Maxiflex PLC. Programmed in any of six IEC 61131 programming languages from ladder to function block using a Windows-based graphical user interface.
The choice of IEC 61131 brings Maxiflex into line with international standards and gives the end user a wide range of programming choices in the Maxiflex programmer's workbench. Control strategies can range from the simple interlock to multiple concurrent PID control blocks complete with auto-tuning.
Not just control
Maxiflex is a completely cross-functional hardware platform that is well established in the RTU, telemetry, control, alarm and events and the data acquisition business. The new P3 CPU dubbed the 'PAC' (process automation controller), which Omniflex has added to the Maxiflex product range, now caters for complete process automation featuring a 32 bit processor and IEC standard programming.
"We have not left our roots behind with this new development", comments Ian Loudon, sales and marketing manager for Omniflex, "We have added this on top of what we have got. Using the new P3 PAC CPU we still give you the automated data acquisition and telemetry capabilities as 'under the bonnet features'. You still do not need to write application programs to do this - it is built into the CPU BIOS saving you time in applications engineering."
Date and time stamped changes of state for sequence of events
This is still a standard feature of the Maxiflex system, even though the user may have an interlock control application running on the CPU they can get each change of state as an event with the real date and time it happened which can then be piped to the scada system database via a network. So the user can now have the sequence of events from their plant with no extra software or costs. The importance of this is not always apparent. The scada can time stamp the changes of state but this only occurs when the event gets to the scada PC. Ordinarily this is fine when the plant network in question has small numbers of I/O... but this is rapidly changing - with many devices sharing the network. Also the scada, by design, continuously polls for changes of state on a fixed routine ie, address 1 to address n. If a change of state happens immediately after address 1 has been read it is only detected on the next scan ie, after address n has been read. Another problem is if the change of state is momentary (and not latched by the front-end device) it can be missed altogether - which is worse still. All Maxiflex CPUs have realtime clocks fitted standard and all have the event service.
Control and advanced monitoring in a single package
Maxiflex can take care of all of this as standard, providing not only the control strategy - but also crucial information for the scada database as to what happened in the plant, and when. Many plant shutdowns and trips rely heavily on the analysis of this information to diagnose the normally complex chain of events.
Remote I/O system
Maxiflex also has comprehensive remote I/O capabilities from Fieldbus level upwards. Using Conet, Omniflex's local area network, Maxiflex already has outstanding ability on existing plant instrumentation cabling. No special cables are necessary. Conet will run up to 10 km on a screened twisted pair cable, allowing 127 nodes to share the same cable, each node with up to 500 I/O on them. Redundant links and topologies such as Star and Bus are easily accommodated. Sharing I/O status information with Maxiflex is very simple and the remote I/O status integrated easily into the control strategy at whatever level is needed.
Open networks and OPC
Maxiflex supports open networking, taking the user from the fieldbus environment right the way up to Ethernet. Using OPC servers to the Windows operating systems environment provides easy connectivity to supervisory systems.
Maxiflex P3 CPU features in summary
* IEC61131 programming - six languages.
* 32-bit processor.
* Remote I/O.
* Open networks.
* Automated data acquisition.
* Automated telemetry.
* Sequence of events - date and time stamped at source.
For more information contact Ian Loudon, marketing and sales, Omniflex, 031 207 7466 [email protected], www.omniflex.com
| Tel: | +27 31 207 7466 |
| Email: | [email protected] |
| www: | www.omniflex.com |
| Articles: | More information and articles about Omniflex Remote Monitoring Specialists |
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