Which of the following statements is true about 'Normally closed' contacts?

The statement that 'Normally closed' contacts always allow current to pass when at rest is accurate. In a normally closed configuration, the contacts are closed in their default state, meaning that when not activated or actuated, they complete the circuit and allow current to flow through. This is fundamental to their operation in various control systems.

The design and application of normally closed contacts are essential in situations where you wish to maintain a continuous current flow unless an event or condition indicates otherwise, for instance, in safety systems where a failure or malfunction should interrupt the current.

This behavior contrasts with other types of contacts that may not pass current when at rest. Understanding the function of normally closed contacts is crucial for wiring and constructing programmable logic circuits, ensuring proper control over devices in both automated and manual systems.