How are electrical interlocks always configured in a system?

Electrical interlocks are always configured in a series arrangement within a system. This series configuration is critical for the proper functioning of safety mechanisms in passenger elevators. When interlocks are placed in series, they ensure that all contacts must be closed before the elevator can operate. This provides a safeguard whereby if any interlock is open or not engaged, the system will prevent operation, thereby reducing the risk of accidents and ensuring that the elevator doors remain closed while the car is in motion.

In contrast, other configurations such as parallel or random could lead to situations where, if one interlock functioned properly while others did not, the system might erroneously allow the elevator to operate, which could compromise safety. Grouped configurations could also pose similar risks if not designed to ensure all necessary safety conditions are met. Thus, using a series configuration for electrical interlocks is a fundamental aspect of elevator safety and operational integrity.