SoftPLC provides a high level of connectivity. Concurrent communications in multiple protocols over various media are supported. SoftPLC RTU's have multiple serial and ethernet ports included as standard, as well as a rich set of communications drivers.

Communications to HMI/SCADA systems, other controllers/RTU's, and process monitoring equipment (eg: energy meters) are supported over high speed LAN (eg: RS-485, Ethernet), WAN (eg: data radio, satellite link, dial-up modem, etc.) or RS-232 serial links. The SoftPLC RTU can support host-initiated, peer-to-peer and slave communications. Communication supports both Point to Point Protocol (PPP) serial communications and direct Ethernet TCP/IP over a variety of hardware interfaces including:

• Multi-Drop Network
• Direct Connection
• VSAT
• Leased Line
• VHF & UHF Radio
• GPRS
• GSM
• OFC
• Ethernet

Supported communication protocols include Modbus, ModbusTCP, IEC-60870-5-101/104, DNP3, and many others. SoftPLC supports point-to-point and broadcast (one to many) modes of communications, including support for (2) IEC60870-5-x Masters.

SoftPLC supports open standards including SNMP, SMS, SMTP, and more. Functions include multiple SNMP managers, SNMP trap notifications (eg: power fail, log full, configuration change, script errors). Individual port diagnostics are available which can notify of alarm state, alarm received attention (ARA) history, output on/off, configuration change.

SoftPLC can also act as a data concentrator, allowing third-party devices and other control systems to be integrated into your SCADA network, by utilizing the SoftPLC RTU communications functions such as time tagging, data logging, and store/forward on all the collected data. SoftPLC RTU can act as a master to collect data from multiple slaves, and concurrently can respond to multiple masters as a slave device.

All operations such as configuration, programming, troubleshooting, firmware updates, and more can be carried out through any available LAN or WAN connection, including a local point-to-point connection via an Ethernet crossover cable.

SoftPLC RTU provides for multiple programming methods. Any method can be used as a stand-alone tool, or in combinations for more advanced applications.

Configuration Tables: The RTU can be configured through a web browser using XML tables (XML version 1.0 - ISO 8859-1 compatible) to enter parameters for standard control operations. This method allows you to easily configure the controllers without any traditional programming required.

Ladder Logic: A rich set of programmable logic functions are available including relay logic, timers/counters, PID, floating point math, data manipulations and comparisons, ASCII input/output, sequencers/shift registers, and many more. Specialty functions are also available, such as SEND EMAIL and COMGENIUS (which provides powerful bi-directional serial string communications).

C/C++: With the SoftPLC Programmer's Toolkit, users can generate custom functions or create entire application programs in C/C++ language.

Over 100M data registers are available, and every bit of every register is addressable in the logic. Data types include bits, integers, floating point, strings, special array structures for PID, timers/counters and others.

SoftPLC RTU's can interface to a variety of I/O systems. SoftPLC Corporation's Tealware I/O system is the local I/O interface. Tealware I/O is a modular system which allows for maximum configurability. The RTU's CPU is separate from the I/O subsystem, offering flexibility and expandability, thus lowering cost and complexity.

The system is expandable to up to (12) I/O racks attached to a single SoftPLC RTU CPU. Each rack can support up to 256 digital I/O (8 modules x 32 points/module), for a maximum capacity of 12 x 256 = 3,072 I/O points per RTU CPU maximum. The racks can reside up to 15 feet from the CPU.

Even with the largest systems, SoftPLC is extremely fast. With Tealware I/O, SoftPLC can scan the I/O in under 1 msec, even with a fully loaded system of 3072 points.

SoftPLC RTU's can also connect to other vendor I/O equipment through serial or ethernet interfaces using protocols such as Modbus and ModbusTCP, among others. With add-on interface boards, I/O networks such as Profibus, DeviceNet, Fieldbus, and others can be used.

SoftPLC RTU's include advanced functions to meet the challenging requirements for utility industries, such as high-speed data capture with time stamping, Sequence of Events (SOE) recording, alarm detection, and more.

SOE resolution is ± 1msec (with Tealware I/O). Data is kept until a delete command is received from the SCADA system. Data can be retransmitted if commanded. RAM and Flash storage is available for acquired data until the SCADA system confirms that it has received the information.