Like any electrical equipment, lifts rely on uptime — especially when carrying hundreds or thousands of passengers per day. However, when issues occur, it isn’t always clear where the problem lies. When spurious switching started to occur in a lift system in a London building, detailed investigations and surveys followed. Having established the lift system wasn’t at fault, the lift’s manufacturer, Schneider Lift Controls, turned to power quality expert CP Automation.

Eight weeks after installation, residents at the apartment complex were experiencing issues with the lifts. There were reports of the fire control input becoming active when the lift was in travel, despite the contact driving the input remaining open.

The fire mode is designed to allow firefighters exclusive access and full control of the lift, allowing them to navigate swiftly and efficiently through the building. The lift descends to the ground floor and is put out of service, but firefighters can reactivate it using a dedicated switch. Because the lift doors close and the system is inactive, passengers couldn’t call the lift from their level and would need to take the stairs.