RCU

The Remote Communications Unit (RCU) is designed to provide reliable, efficient communications from a remote site back to PCG Server. Key features include:

Store and forward

When a communications link can not be obtained to PCG Server for any reason data is stored until a link can be established.

Filtering

Communications costs can be reduced by out certain data items.

Communications Controller

Caching Controller which normally sends latest set of data at a configured cache interval. However full rate data can be automatically sent when a user is viewing a details page for the plant thus still giving "real time" information.

Custom Controller allows a simple controller to be written to control the data flow exactly to the customers requirements. This is useful, for example, when a detailed block of data is to be sent around an event such as a fault.

Efficient communications

Between RCU and Server "PCG Compact Protocol" is normally used with the following advantages:

  • Excellent packet error checking.

  • Compact data size (a quarter of the data size of common "Serialized" protocols).

  • Efficient making is suitable for embedded applications. Protocol specification is available for external vendors to use.

Drivers

One or more drivers (see "PCG Drivers" section) can be used in the RCU

PCG OPC Link

Option to provides standard OPC connectivity to any equipment provider who provides an OPC Server. OPC requires a Windows platform to run

Multiple OS

Runs on any Java 1.6 compliant Operating System

PCG RCU Platforms

To simplify deployment three standard RCU platform options are available:

Industrial PC

A rugged compact industrial PC running Microsoft Windows. These units are capable of communicating with windows based device drivers such as OPC servers and can establish communications over a secure VPN. Communications options include broadband, cellular, wireless, satellite (note some options may require extra hardware).

Embedded PC

Small form factor embedded PC running Linux. This platform is very rugged and reliable with a low power requirement (5 W max). These units are capable of establishing communications over a secure VPN and communications options include broadband, cellular, wireless, satellite (note some options may require extra hardware)

Embedded Module

Small module that can be plugged into a socket on customers electronics PCB. Rugged and reliable with a very low power requirement (1 W max). Can establish communications via broadband, Ethernet, or PPP based communications such as Mobile / GPRS. Up to 512K of battery backed data buffering. Most suitable for simple drivers or custom equipment drivers.

Additionally this functionality can be "plugged" into the server as a LCU (Local Communications Unit). This option is most suitable for connection of equipment that is local to the server.

PCG Drivers

PCG standard modular drivers (most can reside in PCG Server or PCG RCU) include:

  • Modbus TCP

  • Modbus Serial (v3.6 - to be released 2009)

  • Advantech Adam 4k series modules

  • Rockwell SLC500 PLC series DF1

  • OPC driver (requires "PCG OPC Link")

  • Text Driver (allows simple text protocol interfacing via a serial or TCP/IP port)

  • SAM80

  • DNP3 (V3.6 - to be released 2009).

  • SNMP(V3.6 - to be released 2009).

  • WirelessPlug (PCG Server only)

  • XML RPC (PCG Server only)

In addition PCG Server was designed to be able to talk to a wide range range of unusual equipment using PCG Custom Driver. Custom drivers are written in Java using a well defined driver Application Programming Interface (API).