Why are safety controls placed in series the loads they are protecting?

Safety controls are placed in series with the loads they protect to ensure that if one control fails or detects a fault, it can immediately interrupt the power supply to the load, minimizing the risk of accidents or equipment damage. This arrangement creates a fail-safe mechanism, where the effectiveness of the safety controls is dependent on their ability to operate independently and consistently. By being in series, they provide a direct path for power interruption, ensuring a quick response to safety hazards. Thus, this configuration enhances the overall safety and reliability of the system.