A building has five elevator cars controlled by one machine room using a single large hoistway. What is the minimum number of circuits required for the elevator fire alarm recall and warning system?

A building has five elevator cars controlled by one machine room using a single large hoistway. What is the minimum number of circuits required for the elevator fire alarm recall and warning system?

• A. 2 circuits
• B. 4 circuits
• C. 3 circuits
• D. 5 circuits

Answer: (C)

In elevator fire fire-life safety design, recall and warning circuits must be divided so that a fault on one circuit doesn’t take down recall for every car. With five elevator cars in a single hoistway, you need to distribute the control and warning loads across multiple circuits rather than putting all cars on one circuit. The smallest reliable split is to assign two cars to one circuit, two cars to another, and the remaining car to a third circuit. That way, even if one circuit has an issue, the other circuits can still perform recall for their respective cars, and the warning devices for those cars remain functional. Therefore, the minimum number of circuits required is three.

In elevator fire fire-life safety design, recall and warning circuits must be divided so that a fault on one circuit doesn’t take down recall for every car. With five elevator cars in a single hoistway, you need to distribute the control and warning loads across multiple circuits rather than putting all cars on one circuit. The smallest reliable split is to assign two cars to one circuit, two cars to another, and the remaining car to a third circuit. That way, even if one circuit has an issue, the other circuits can still perform recall for their respective cars, and the warning devices for those cars remain functional. Therefore, the minimum number of circuits required is three.