Alarms, control panel design

Design according to frequency of use or importance. Controls and displays that are frequently used or are of special importance (e.g., critical alarms), should be placed in prominent positions, for example, near the center of the control panel. 

A control panel should be laid out in an orderly fashion, where indieator lights are clearly labeled, colors correspond to the severity of the alarm, and the most important information is presented at the top of the center of view. Attention shonld conform to the normal left-to-right reading pattern and the confignration shonld minimize confusion or misinterpretation. (Redrawn from Wolfe, N.T. and Odom, J.A., Control Panel Layout Design Guide, Honeywell Microswitch, Freeport, IL, 1976.)... 

The main features of the control system of the plant are reported here. A dedicated programmable logic controller (PLC) handles both regulation loops and an alarms-interlocks system. If any process condition exceeds the design values, a trip system is activated and an interlock sequence restores a safe state. The control panel operator monitors alarm indicators and may take appropriate action when needed to avoid a plant shut-down. 

A control room configuration was established (see CESSAR-DC Section 18.6) based on accepted HFE principles and on analysis of staffing requirements. Environmental and communications criteria for the ACC were also developed at this time. Standard panel design criteria and algorithms for alarm and parameter validation processing were then developed. 

First, the following components will have to be included into the operational behavior analysis the mechanical design of the valve, the hydraulic control element, the control pulse, the position transmitter of valve (2), the manual control of valve (2), the operation of the manual control element by the operator from the control panel, the acoustical alarm sounded for faulty positioning, and the information on the operational mode of the valve (visual display). Furthermore, a second position indicator (2z) is introduced as an additional component. The function of the acoustical alarm and the level indicator are dependent on the proper functioning of the position transmitter. An analysis based on the decision table (see Figure 5.23) provides the following information. 

Designate on your flowsheet the indicators that are displayed on the control panel also show which valves are controlled from the control board. Mark all the level alarms on your flowsheet. Find the mercuroid switches or level float pots outside that activate the inside level alarms. These are located on the process vessels. With a crayon, indicate their functions. 

The reactor protection system (RPS) is a safety-related system that is designed to monitor key operating plant variables and to cause alarms, control rod insertions, or scram, as the occasion may require when off-normal conditions occur. The reactor trip system (RTS) is part of the RPS and includes those power sources, sensors, initiation circuits, logic matrices, bypasses, interlocks, racks, panels, control boards, actuation devices, and actuated devices, that are required to initiate reactor shutdown. The RTS automatically initiates control rod insertion when required to assure that acceptable fuel design limits are not exceeded. It is designed to fail safe for most internal component failures. The RTS can also be actuated manually by operator action. 

A main control and annunciator panel should be installed when the fire alarm system requires more than a single alarm zone. The panel should be installed in the control room or other continuously staffed location. Separate detection zones should be provided for each distinct fire area and identified by a permanent label. A detailed map of the area should also be provided at the annunciator that identifies which zone relates to which annunciator lamp. Systems with more than ten separate zones should be provided with an electric or electroniczone "mimic" panel showingthe location of all alarms on the graphic display of the platform. Basic arrangements of equipment and system design should be in accordance with NFPA 72. A locked main fire panel and control cabinet should be provided. 

The KNGR introduces a lot of brand-new human-machine interface (HMI) design features in nuclear industry of Korea, such as workstation-based control room Large Display Panel whieh provides a bird s view of plant condition the CPS which shows all operation procedures Soft Controls using toueh screen which can control both safety and non-safety components advanced alarm system using prioritization and filtering. 

The main control room accommodates an operator console, a supervisor s console, safety consoles, the wall panel information system large screen displays and the DAS panel. The operator console provides the displays and controls to start up, manoeuvre, and shut down the plant, and it is designed to be staffed by one to six operators. The operator interfaces are the duty system control displays, soft controls, alarm presentation system displays, computerised procedures displays, as well as the VDU monitors, keyboards and mice. The supervisor s console is a smaller version of the operators console, and is designed to be staffed by one or two personnel. The primary dedicated safety panel and VDU-based safety system workstations are located at the centre of the operator console, with a secondary safety panel located in close proximity to the supervisor s console. The DAS panel is located at a sidewall in the main control room. The main control room also includes communication devices, document lay down areas, printers and storage space. A meeting table is provided and equipped with a VDU-based workstation to allow access to the duty control system by, for example, a technical advisor or shift manager, without disrupting control room operations. In close proximity to the main control room are the shift supervisor s office, the operations staff area, an operations woik area, restrooms, and kitchen facilities. 

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