Instrument Data sheet /Specification

What is instrument datasheet or specification?

An instrument data sheet is a document that gives the technical details of an instrument or device.

A datasheet will tell you everything you need to know about the equipment’s features and technical specifications. The data sheet contains considerably more detailed information that is tailored to the application.

Detailed Explanation of Instrument Datasheet/Specification:

         The instrument datasheet is important because it tells you what kind of instrument is needed to meet the key parameters of the process. The instrumentation datasheet contributes to enhanced process monitoring and plant security. The instrument data sheet is created by the instrumentation process engineer.

What is the purpose of an instrument data sheet or specification?

Instruments and equipment have mechanical, electrical, and control specifications that are written down on data sheets. The data sheets have information about the desired spare parts. Usually, the vendor gives you the data sheets after you buy something from them.

Once complete, the data sheet is delivered along with a request to many vendors. When giving their estimates, vendors will list a variety of models and manufacturers. The job of the instrument engineer is to look at each quote and choose the one that meets technical standards.

After technical and economic considerations, the instrument is purchased. The vendor sends documents and drawings after getting the purchase order. Using vendor data, an instrument’s data sheet can be changed to reflect “as-built” details.

Data sheets and vendor data are saved in a library or document control room for construction, operation, and maintenance.

What is included in the instrument datasheet and specifications?

Data sheet lists general information about the instrument, such as its

  • Tag number
  • Product name and Model Number
  • Service description and its intended use
  • Location (line number or equipment number)
  • P&ID number or drawing number
  • Detailed technical specifications, such as measurement range, accuracy, resolution, and precision
  • Operating conditions, such as temperature, humidity, and pressure range
  • Electrical requirements, such as power input, voltage, and current
  • Material
  • Performance characteristics, such as accuracy, linearity, response time, stability, and sensitivity
  • Physical dimensions and weight of the instrument
  • Safety features and precautions, Hazardous certification (for an electrical device)
  • Maintenance and cleaning instructions
  • Calibration and repair information
  • Warranty and support information
  • Accessories needed, etc.

Each type of instrument, such as a transmitter, switch, gauge, or control valve, may have different information in its data sheet.

How do you create an instrument datasheet?

Creating an instrument datasheet requires gathering and organizing detailed information about the technical specifications, performance characteristics, and operational capabilities of the instrument.

Here are some steps you can follow to create an instrument datasheet:

Step1: Identify the purpose and intended use of the instrument. This will help you focus on the most relevant information to include in the datasheet.

Step2: Gather information about the technical specifications of the instrument. This might include the measurement range, accuracy, resolution, and precision of the instrument, as well as any other relevant technical details.

Step3: Collect information about the performance characteristics of the instrument. This might include the response time, stability, and sensitivity of the instrument, as well as any other relevant performance data.

Step4: Determine the operating conditions of the instrument, such as the temperature, humidity, and pressure range in which it can be used.

Step5: Obtain physical dimensions and weight data for the instrument.

Step6: Determine the electrical requirements of the instrument, such as the power input, voltage, and current.

Step7: Include information about any safety features or precautions that should be taken when using the instrument.

Step8: Provide instructions for maintaining and cleaning the instrument.

Step9: Include information about calibration and repair, as well as warranty and support information.

Step10: Organize the information in a clear and concise manner, using tables and bullet points to make the information easy to read and understand.

Step11: Review the datasheet for accuracy and completeness, and make any necessary revisions.

It can be helpful to use a template or examples of other instrument datasheets as a guide when creating your own.

What are the documents required to prepare instrument datasheet?

         The instrumentation process engineer creates the instrument data sheet.

To make a data sheet, you need to have the following documents such as

  • P&ID(piping and instrumentation diagram)
  • HMB(Heat and Material Balance )
  • Line List
  • Specification of Instrument
  • Specification of Pipes
  • Calculation of instrument
  • Catalog from Vendor.

The work flow is described by the following steps:


P&ID helps give out general information like the number of the instrument tag, a description of the service, the line number or equipment number, and the P&ID number.

Process data:

When choosing an instrument, you should know the type of fluid, its state (gas or liquid), the design pressure, the operating pressure, the design temperature, the operating temperature, the flow rate, the density, the viscosity, the specific gravity, the ratio of specific heat (gas), and the molecular weight (gas). But, depending on the type of instrument, the process data that needs to be written on the data sheet is different.

Project requirements:

The company has a specification outlining the basic instrumentation requirements. It also lists the standards that must be used on instruments so that the specifications for each instrument are the same all over the plant. This is meant to reduce the number of replacement parts and tools as well as facilitate maintenance.


Some instruments must be calculated in order to have the correct dimensions. This calculation is required before preparing a data sheet. Some instruments whose sizes must be figured out are a control valve, a pressure safety valve, an orifice plate, and a thermowell.

Vendor catalog:

When making a data sheet, it’s a good idea to check the vendor catalog to make sure the device is available for sale. If you skip this step, it might be hard to find the instrument during the procurement phase. If the instrument is not available on the sale, the design could be changed. This includes both the design of the instrument and the design of the process. In addition to rework, it may also result in project delays.

Code and Specification:

Last but not least, there needs to be a cross-check with the relevant code and standard, even though this issue has been mostly covered in the project specification.

Why an Instrument datasheet is important?

There are several reasons why an instrument datasheet is important:

It helps users understand the capabilities and limitations of the instrument, which is essential for choosing the right instrument for a particular application or task.

It provides information on how to properly operate and maintain the instrument, including any safety precautions that should be taken.

It can help users troubleshoot problems or issues that may arise when using the instrument.

It can help users understand the performance and accuracy of the instrument, which is important for ensuring reliable and accurate results.

Overall, an instrument datasheet is an essential resource for anyone who uses or works with a specific instrument or device. It provides important information that can help users make informed decisions and ensure the proper use and operation of the instrument.

What is the difference between datasheet and specification?

A Datasheet and a specification are both documents that provide information about a specific product or device. However, there are some key differences between the two.


  • A Datasheet is a document that provides detailed technical information about a specific product or device.
  • It can include information such as the technical specifications, performance characteristics, and operational capabilities of the product.
  • Datasheets are typically used to help users understand the capabilities and limitations of a product, and to help them choose the right product for a particular application or task.


  • A specification, on the other hand, is a document that outlines the requirements or standards that a product must meet in order to be considered acceptable for a particular use or application.
  • A specification can include information such as the materials, dimensions, performance standards, and other requirements that a product must meet.
  • Specifications are typically used to ensure that products meet certain quality standards and are fit for their intended use.

In summary, a datasheet provides detailed technical information about a specific product or device, while a specification outlines the requirements or standards that a product must meet in order to be acceptable for a particular use or application.

Example Instrument Datasheet:

The instrument data sheet for the differential pressure transmitter used for level measuring purposes is shown in the example below.

Instrument Data sheet /Specification 1

Sundareswaran Iyalunaidu

With over 24 years of dedicated experience, I am a seasoned professional specializing in the commissioning, maintenance, and installation of Electrical, Instrumentation and Control systems. My expertise extends across a spectrum of industries, including Power stations, Oil and Gas, Aluminium, Utilities, Steel and Continuous process industries. Tweet me @sundareshinfohe

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