My wife bought a water pump for a small outdoor fountain, and I was surprised to see that there is no external LV transformer. That is, the 240v cable is immersed in the water and goes straight to the small pump, which the seller said is double insulated.
240v cable in water doesn't sound OK to me - would this have passed electrical standard testing??** A maker can simply label a product as being "double insulated" or apply the double square symbol if they believe it complies with all the requirements of "Class 2" insulation.
The exceptions are those devices on the "prescribed items " list which must be submitted to a registered lab for standards approval. AFAIK submergible pool pumps are not on the list.
If the pump is fitted into a sturdy, all plastic, watertight enclosure - compliance with class 2 rules is simple.
240 volt submergible pumps for indoor and outdoor fountains are widely sold and seem to have ordinary AC power leads. Maybe the outer plastic is UV proof and tougher than usual.The 24 volt ones have an advantage when the pump is sited well away from an AC outlet - since a 24 volt cable can be run across ground or shallow buried without the special protection needed for a 240 volt one.
.......... Phil
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