How Different Is Instrumentation Compared To Power Engineering?

This forum has a user who asks roughly the same question as you. If you scroll down to the response by user sneddens you will see an explanation. He roughly says that a power engineer often works on industrial boilers in a plant while an instrumentation engineer has more specialized knowledge to tune and repair instrumentation and controls.

Here are some general job descriptions that you can read that might help further distinguish the two types.

Power Engineer Job Description

Power Engineer Job Description

Control and Instrument Engineer

Instrumentation Engineer

Before applying to any job, you should read the job description and qualifications line by line. It can be helpful to skip the description to read the qualifications first, then go back and read the description. Every company's job description is going to be a little bit different. And job titles do not always mean the same thing between organizations.

The power engineer may have a role in designing the entire power cycle, what tools and instruments are necessary to implement such an installation, whereas the instrumentation engineer will design and implement controls and instruments to ensure the plant can be safely operated within performance criteria, and who will ensure a sensible and easily operated interface between human users and the machine.