The design institute provides electrical power conditions for instruments and utilities
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How can the design institute specify the electrical requirements for instruments and control systems? Knowing only the number of instruments on site and some signals related to the remote start/stop and fault operation of pumps, how can one calculate the electricity consumption required to meet these needs?
To provide the electrical system with the necessary power supply for the instruments in the design office, the following steps are required: 1. Determine the number of instruments: Decide how many instruments need to be installed based on the equipment and process parameters that need to be monitored on site. The rated voltage and rated power of each instrument also need to be taken into consideration. 2. Calculate power consumption: Based on the rated voltage and rated power of each meter, calculate the power consumption for each one, and add these values together to obtain the total power consumption. 3. Determine load characteristics: Determine the load characteristics of the electrical system based on the fault operation signals for remote start/stop of the pump. For example, if there are many devices that start and stop frequently, the impact of instantaneous load and concurrent load must be taken into account. 4. Select the power supply method: Choose an appropriate power supply method based on electricity consumption and load characteristics. For example, equipment such as distribution cabinets, transformers, and UPS can be selected to provide stable power. 5. Develop a power usage plan: Based on the steps above, create a detailed plan for power usage, including wiring diagrams of the instruments, connection methods, and power supply approaches. In summary, for the design institute to provide the electrical system with the necessary power supply conditions, it is necessary to conduct a thorough analysis of the site conditions, take various factors into account, and develop a reasonable power supply plan to ensure the safe and stable operation of the electrical system. .
HG T 20509-2014 Specifications for Power Supply Design of Instruments
No, it’s not the instruments that provide conditions for the electrical system; rather, it’s the process that does that. The control points of the electrical system then provide conditions for the instruments. For example, aspects such as the operating/faulty/local or remote status of a pump, remote start/stop/starting and stopping via DCS interlocks/SIS interlocks, variable frequency control, and requirements for on-site control panels are all determined based on the requirements of the process. Process parameters are provided to the electrical and automation systems.
The original poster is talking about power supply conditions and electrical load – where on earth has this gone off-topic?
This post was last edited by mutianly on 2023-5-17 at 15:10 :L;P. We, as DCS equipment manufacturers, calculate the amount to be returned to the design institute
Design firms generally have a \"Table of Power Requirements for Instruments,\" and one can simply fill it out according to that table.
Aren’t instruments usually connected to the control cabinet? During the design phase, calculate the total power required to power the cabinet inside the control cabinet; also calculate the total power that needs to be supplied separately, leaving some margin, and submit this information to the electrical team. Are pumps also considered instruments?
Do you need a meter? Engineer Huang from Anhui Tiankang Instruments: 18225806021