Single pole, double pole, two pole

A single-pole device breaks only the live conductor. A double-pole device breaks live and neutral together in one operation. Two single-pole devices side by side look similar but are not the same thing: they operate independently and carry separate ratings.

Where double pole is used

Circuits where the neutral must be isolated with the live conductor

Equipment with a functional earth or electronic supply

Three-phase boards where a single-phase outgoing circuit needs both poles broken

Situations where isolation of the neutral is required for safe maintenance

What to check

That the device breaks both poles simultaneously

The rating of each pole

Whether the neutral is switched or solid

Whether the device is suitable for the earthing arrangement of the installation