Question

Q1. Explain how digital inputs are used in a SCADA system and what applications they normally perform.

Q2. Briefly explain the meaning of “tagged slot”, and give at least five (5) examples of data points.

Q3. Discuss human and ergonomic factors in alarm systems. Include in your answer a simple figure showing correct position of the operator to the system.

Answer 1

Hello,
       Please find the answer to Q1 attached below. If the answer has helped you please give a thumbs up rating. Thank you and have a nice day!

Digital inputs and outputs are typically processed in a SCADA system using Digital Input-Output modules. Inputs to a typical SCADA system may include Temperature, Pressure, Flow rate, Humidity, Level etc which are processed as Analog Inputs. Inputs from Flow switches, level switches, Pressure switches, Proximity switches, Limit switches, auxiliary contact of contactor etc are processed as Digital Inputs.

Digital inputs may also include alarm handling functions. The system monitors whether certain alarm conditions are satisfied, to determine when an alarm event has occurred. Once an alarm event has been detected, one or more actions are taken (such as the activation of one or more alarm indicators).

Digital inputs are also used to relay control signals from the Digital computer to the Control unit within the SCADA, where the SCADA unit scans the signals and takes appropriate control action.