Various terms are used repetitively throughout the ICScada documentation. This section of the manual serves to clarify what we mean when we use them and how they apply to the ICScada system.
Access Control
User Access Control (or UAC) is used by an administrator to assign rights to individual users that dictate what they can and cannot access or modify in an ICScada system.
Alarm
ICScada can be configured to notify operators when certain conditions have been met or exceeded. These are referred to as alarms.
Alarm Recipient
When an alarm is triggered it will send a status indication to an alarm recipient. Email addresses and telephone numbers are examples of valid ‘recipients’.
Area
A number of sites can be organized into an area. A single project can consist of a number of Areas.
Aserver
ICScada runs a software module called Aserver (short for Acquisition Server) which is responsible for communication with the attached devices and gathering information from them.
Browser
An operator interacts with an ICScada server by using a web browser, even in the case of a non-internet-enabled system. The client machine still needs to access the HMI (which is served up by the ICScada system) from a browser. We recommend using an up-to-date browser that is compliant with modern web technologies (eg. Firefox and Chrome are both known to work well). In our experience, Microsoft Internet Explorer has shown to have numerous inconsistencies.
Data Logger
An ICScada data logger can be configured to periodically gather data from devices and record it so that it can be reported or trended later. This involves gathering data from a set of points or registers and storing them into a database.
Data Profile
A properly configured data profile is a prerequisite for trends and reports to work in ICScada. The data profile configures which tags to listen to and log.
Database
ICScada keeps track of all data at the server via a software database. A set of tables stores values pulled from equipment and also configuration information about the ICScada system itself. As a particular project ages, the database can grow proportionally in size.
Device
ICScada is configured to communicate with one or more devices over a communication link. A device might be an RTU or a meter or any other SCADA compliant units that can talk using a standard protocol such as Modbus or ROCtalk.
Document
ICScada provides document upload and access control features.
Group
ICScada organizes users into groups such as operator, advanced operator, engineer, ‘ ’view only’, etc. which dictates what level of access and control they have to different parts of the ICScada HMI.
History Database
Data for reports and trends are stored in a database known as the history database.
HMI Template
The HMI or (Human Machine Interface) is controlled via templates which are modifiable by developers using a combination of modern web technologies. Many projects can take advantage of a template when several sites have similar equipment and so they are all presented via the same template.
HTTP Server
All human interaction in a browser is called up from and sent back to an HTTP server. The HTTP Server serves up web content such as HTML, XML and JavaScript. The HTTP Server is an integral part of an operational ICScada server.
ICS Server
A module called the ICS Server does most of the processing in an ICScada server. It manages data that flows in and out of the Aserver module using control logic and checks for alarm states.
ICS Service
The ICS Service is the coordinating module in an ICScada server. Its responsibilities include performing backups and dispatching alarms. ICS Timer: A module called the ICS Timer is used to schedule events.
Log
Information gathered from equipment can be gathered and saved at specific interval into a log. The data from the log can then be reported or trended.
Modbus Master
For the modbus protocol to work one end of the communication must act as master, that is, it will act as the controller and will initiate most of the communication.
Modbus Slave
When a pair of modbus devices communicate, the master will send control requests to the slave and the slave will respond in turn.
PLC
PLC is an acronym for Programmable Logic Controller. A PLC is home to a digital microcontroller and memory registers. It allows a programming engineer to write code that will control equipment. Traditionally, PLCs are more customizable versions of RTUs but modern SCADA systems have blurred the distinctions between them.
Polling
Periodically a server will query a SCADA device for new information. A poll consists of the server sending a query to a device and then that device responding in turn by sending back information that satisfies the request.
Profile
A data profile is used by the ICScada trending engine to access data from logs. A profile describes which tags contain the pertinent information.
RTU
RTU is an acronym for Remote Terminal Unit. Essentially it is an electronic device controlled by a microprocessor. In an ICScada system, RTUs are typically used to communicate equipment and to act as smart controllers. They will perform of the semi-automated activations of the equipment and relay information regarding the status back to the ICScada system. They will also pass requests from ICScada on to the equipment. They serve as a sort of relay station between the ICScada server and the equipment being operated. See also PLC.
Site
In ICScada site refers to a single location that is host to a set of equipment. Typically there is a single HMI associated with a site, but there can be more.
Tag
An ICScada system communicates with devices by accessing tags. A tag will usually occupy one or a series of registers on an RTU or PLC and has to be configured specifically for the equipment in question. The result is that ICScada can then read or write these tags directly from the HMI.
Trend Profile
A plot of tag values over time is called a trend graph and the trend profile is used to configure the appearance of the graph. User: By using UAC (User Access Control) users can be managed by an administrator and assigned different access levels according to a unique login assigned to each operator.