Is it safe to leave the power supply outside? What happens if there is a thunderstorm?
What to know.

The power supply unit should be used in a covered, shaded area protected from the outdoor elements, including rain, heat, and cold. If the robot is set on a weekly timer, the power supply should be left plugged in.
We recommend mounting the power supply on the Dolphin caddy or placing it on a higher surface away from the edge of the pool.
The power supply unit should be positioned at least 12ft (3.5m) from the pool. The power supply is splash-resistant, but not waterproof. Do not allow the power supply to be submerged in the pool or standing water.
Always use an electrical outlet protected with a Ground Fault Circuit Interrupter (GFCI) device; (this will protect the power supply from unexpected power surges).
Source: Maytronics support. Rewritten for clarity with the same steps; the videos and illustrations are Maytronics' own.
Parts that fix this.
This answer comes down to power supplies & chargers. The exact part depends on the model: choose your robot and we open its parts list, or browse the category for every model.
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