Understanding the subtle differences in switch types can be challenging, particularly when it comes to switch action, and the number of steps involved.

In a single-step switch, both circuits activate simultaneously. For instance, when a button is pressed, a mechanical detent is felt. As pressure continues to be applied, both circuits are triggered at once. Upon release, both circuits reset simultaneously, allowing the button to return to its resting position. Therefore, a single-step switch is ideal when two independent circuits need to activate concurrently.

Conversely, a two-step switch activates its circuits sequentially. Similar to the single-step switch, a mechanical detent is felt when the button is pressed. However, with a two-step switch, the first circuit actuates immediately following the detent being felt. As the button is pressed further, a second mechanical detent is encountered, triggering the second circuit. Upon release, the second circuit resets first, followed by the second detent, and then the first circuit resets, returning to its original position with the initial detent.

A two-step switch is best suited for applications where events must occur in sequence. This makes the two-step option ideal for events that need to occur consecutively.

A practical application of a two-step switch can be found in the operation of an x-ray machine. When the operator engages the switch to the first position, it activates warning lights connected to the system, signaling individuals in the vicinity that the x-ray process is imminent. If the operator proceeds to the second position by continuing to depress the switch, the x-ray will be taken. However, if the operator reaches the first step and observes any movement from the patient or identifies a person who is too close, they can release the switch. This effectively resets the system and prevents unintended exposure.

For a pushbutton featuring two SPST (Single Pole, Single Throw) circuit forms, such as pushbuttons in OTTO's P2 series, the switch will have two distinct SPDT (Single Pole, Double Throw) circuits, resulting in a DPDT (Double Pole, Double Throw). If the switch also features a two-step action, the circuits will be activated sequentially.