Re: storable or permenant?
Permanently Installed Swimming, Wading, and Therapeutic Pools.
Those that are constructed in the ground or partially in the ground, and all others capable of holding water in a depth greater than 1.0 m (42 in.), and all pools installed inside of a building, regardless of water depth, whether or not served by electrical circuits of any nature.
Storable Swimming or Wading Pool.
Those that are constructed on or above the ground and are capable of holding water to a maximum depth of 1.0 m (42 in.), or a pool with non-metallic, molded polymeric walls or inflatable fabric walls regardless of dimension. See the commentary following 680.30 and Exhibit 680.16.
NEC HANDBOOK 2002 Edition
Originally, storable pools were not specifically addressed in the NEC. Article 680 was written to provide guidance relative to permanent, in-ground pools and their unique construction requirements because of the unusual earth-water-electricity-human body environment created in the finished product. The conductivity of moist concrete or metal walls buried in the ground, the incorporation of large masses of reinforcing steel, and the inclusion of stainless-steel handrails and diving-board stands as well as 120-volt lights in the pool structure all called for the strict wiring, bonding, and grounding requirements of Article 680.
Storable pools, on the other hand, are intended to be temporary structures, without the need for special wiring or modification to the pool site. They are usually sold as a complete package, consisting of the pool walls, vinyl liner, plumbing kit, and pump/filter device. A storable pool is often disassembled and stored during the winter months. Regional preferences, weather patterns, economic considerations, and design characteristics of the pool are all factors influencing this action. The original Article 680 definition of a storable pool was ?One that is so constructed that it may be readily disassembled for storage and reassembled to its original integrity.?
Part III of Article 680 was created to address the special equipment specifications of storable pools, and Underwriters Laboratories developed testing and labeling criteria for listing the pump/filter units designed especially for these pools. This equipment has the following notable aspects:
(1) It must have an approved system of double insulation or the equivalent.
(2) It is permitted to have a flexible cord equipped with a parallel-blade, grounding-type attachment plug for electrical connection.
(3) It must have a grounding conductor included in the flexible cord.
(4) The flexible cord is not limited to 3 ft, as required in 680.7, and is specified by UL to be not less than 25 ft long. This length was chosen to discourage the use of extension cords.
The UL labeling requirement for these listed units includes the wording ?Do Not Use with Permanently Installed Pools.? In some cases, consumers and members of the swimming pool industry, however, have found it desirable to use these pump/filter units on any aboveground or on-ground pool, regardless of the pool's dimensions or ?storability.?
Storable pools are supplied as two distinct types. One type is intended to be disassembled at the end of each swimming season. The second type, by the nature of its construction, can be disassembled, but manufacturers recommend leaving it assembled. The pools in the latter category frequently require special modification to and preparation of the pool site, making them impractical to disassemble. Draining these pools, especially the larger ones, increases the likelihood of costly damage caused by shrinkage of the vinyl liner material.
The main factor differentiating the two types of pools is wall height. Generally, pools, other than the inflatable type, intended to be disassembled at season's end have wall heights of 42 in. or less, while those not intended for disassembly have wall heights of 48 in. or more. The surface area of the pools is not a factor. Inflatable pools are treated as storable pools regardless of their wall height.