To add equipment in a location, navigate to Plan Viewer section (Web - Plan Viewer) and click on exiting location on the plan . A popup modal will be shown so you can click on Add Equipment
When you click on Add Equipment , a new icon for equipment will be set on the plan with ability to drag it to the exact position.
When clicking on Apply, a new popup modal will appear to set the equipment info . You can fill the equipment info from existing equipment already available in the project.