Which of the following is essential for ensuring power supply stability in a PLC?

Ensuring power supply stability in a Programmable Logic Controller (PLC) system is critical for maintaining operational integrity and minimizing the risk of failures. Redundant power supplies are essential because they provide a backup source of power; if one supply fails, the other can keep the system running, thus preventing downtime. This redundancy helps ensure continuous operation, which is crucial in industrial settings where even minor interruptions can have significant repercussions.

Uninterruptible Power Supply (UPS) systems are also vital as they provide emergency power when the main power source is interrupted. This is particularly important in environments where sudden power loss could lead to data loss, equipment damage, or safety hazards. A UPS ensures that the PLC and associated systems can function long enough to safely shut down or switch to an alternative power source, thereby enhancing overall reliability.

Surge protectors serve to safeguard the PLC from voltage spikes and surges that can occur due to lightning strikes, power outages, or other electrical disturbances. Such spikes can seriously damage PLC components and disrupt operations, making surge protection an important aspect of electrical safety and equipment longevity.

Therefore, all these components—redundant power supplies, UPS systems, and surge protectors—are essential in ensuring the stability of the power supply to a PLC. They