The ClearSCADA system uses Points to represent the measuring instruments and control devices on your system. For each measuring instrument or control device on your system, you need to add and configure a corresponding Point of the appropriate type in the ClearSCADA database (see Types of Point used in ClearSCADA and see Configuring a Point). Points allow the corresponding plant to be measured or controlled from the ClearSCADA server.
Many drivers support both input points and output points. An input point receives its value from the corresponding measuring instrument on your system. The outstation, PLC, data logger, or other device to which the instrument is attached reports its value to the ClearSCADA server, which uses the input data to update the values in the ClearSCADA database.
An output point is used to control a device on your system. An operator or engineer sends a control from the ClearSCADA server to the outstation, PLC, or scanner. From there, the control is sent to the control device. A maintained control, sent via a digital output point, changes the state of plant until another control is sent to further alter the state. A pulsed control, sent via a pulse action, changes the state of plant for a defined period of time.
NOTE: Internal points differ from other points in that they do not physically exist on your system—they only exist within the master station software (see Internal Points).
This guide provides information on how to configure the analog point, digital point, counter point, string point, time point, and pulse action details on both simple and advanced drivers. For more information, see the following topics:
- Types of Point used in ClearSCADA
- Configuring a Point
- Defining Analog Point Details
- Defining Digital Point Details
- Defining Counter Point Details
- Defining String Point Details
- Defining Time Point Details
- Defining Pulse Action Details.
This guide also includes sections on:
- How to Detect Whether a Point Value has Stopped Changing
- Defining Historic Details for a Point
- Promoting Scanning of Outstations Associated with Controls
- Multiple Point State Alarms.
Many points also have configuration that differs, depending on the type of driver. For information on such configuration, see the driver-specific documentation.
Some drivers support other types of point. Configuration of these points is covered in the driver-specific documentation. Many of these points have analog-, counter- or digital-type processing, and therefore many aspects of configuration explained in this guide also apply to these point types. The driver-specific documentation indicates when another point type has analog-, counter- or digital-type configuration.