What is the scope of your past electrical work? Have you done much with high voltage commercial for instance?
Your pre-interview preparation should have helped you to organize a presentation of your experience as a professional electrician. You should be able to talk about the scope of what you've done in your career and where you're headed. It may be a good time to step the interviewer through your resume in general terms, touching on the more complicated or sizeable projects you've done. Talk about your commercial experience if any but focus on the areas that are most important to the job you're interviewing for. It's always a good idea to end your response with a question such as, "Did that answer your question or would you like more information?" just to make sure the topic is put to rest before moving on.