[Swimming Pool and Spa Equipment] Swimming Pool and Spa Transformers, WDGV

See General Information for Swimming Pool and Spa Equipment



This category covers field-installed, air-cooled swimming pool and spa transformers and dc-output power supplies of the isolated two-winding type having a grounded metal barrier between the primary and secondary windings, and intended to supply swimming pool, spa or submersible (fountain) luminaires in accordance with Article 680 of ANSI/NFPA 70, "National Electrical Code." The input is rated a nominal 120 V; the secondary is rated 15 V ac or less or 30 V dc or less and 1000 VA or less.

These products are provided with a power-supply cord or have provisions for conduit connection to the branch-circuit supply. Transformers not provided with a power-supply cord are provided with leads or with studs or terminal pads to which certified pressure-wire connectors can be factory or field installed to accommodate field wiring. Wire-binding screws or studs with cupped washers should be used for copper wire 10 AWG max.

Transformers provided with a power-supply cord are intended for supplying low-voltage submersible (fountain) luminaires as indicated by a marking on the transformer. They are not intended for use with a swimming pool or spa luminaires.

Unless marked otherwise, these transformers are not suitable for connection to a conduit which extends directly to a wet-niche or no-niche luminaire.

These products have not been investigated for outdoor use, unless marked "For Outdoor Use" or equivalent, in which case they are acceptable for both outdoor and indoor use.


One of the following product identities appears on the product:

    Fountain, Swimming Pool or Spa Transformer

    Fountain Transformer

    Spa Transformer

    Swimming Pool Transformer


For additional information, see Swimming Pool and Spa Equipment (WABX), Electrical Equipment for Use in Ordinary Locations (AALZ) and Plumbing and Associated Products (AAPP).


The basic standard used to investigate products in this category is ANSI/UL 379, "Power Units for Fountain, Swimming Pool, and Spa Luminaires."


The Certification Mark of UL on the product is the only method provided by UL to identify products manufactured under its Certification and Follow-Up Service. The Certification Mark for these products includes the UL symbol, the words "CERTIFIED" and "SAFETY," the geographic identifier(s), and a file number.

Alternate UL Mark

The Listing Mark of UL on the product is the only method provided by UL to identify products manufactured under its Listing and Follow-Up Service. The Listing Mark for these products includes the UL symbol (as illustrated in the Introduction of this Directory) together with the word "LISTED," a control number, and one of the following product names: "Fountain Transformer," "Swimming Pool Transformer," "Spa Transformer" or "Fountain, Swimming Pool or Spa Transformer."

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UL, in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. UL shall not incur any obligation or liability for any loss, expense or damages, including incidental or consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Guide Information.

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Last Updated on 2014-05-02
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The appearance of a company's name or product in this database does not in itself assure that products so identified have been manufactured under UL's Follow-Up Service. Only those products bearing the UL Mark should be considered to be Certified and covered under UL's Follow-Up Service. Always look for the Mark on the product.

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