On Underwater Pool Lighting

The National Electric Code 680.24(A) and (B) require that the wiring for any underwater pool lighting terminate in an approved junction box. This code requirement does not differentiate between low or high voltage lighting.

Approved junction boxes must be installed 8″ above the maximum possible water level (if someone overfilled the pool, that resulting overflow level is the maximum water level). The junction box must also have strain reliefs for the light cords. For high voltage lighting, these strain reliefs are critical.

When a light is serviced, the wire nut connections could be compromised if pulled on, exposing the conductors. Another reason for a junction box is that it provides an air gap between the vessel and power supply panel. This help reduce the transmitted water vapor from the lighting conduits into the circuit panel. It also separates the lighting wires from the circuit panel.

If the lighting cord is pulled on, then wires in the circuit panel or connected to the breaker are not compromised. Running the lighting conduits directly into the circuit panel is not permitted by code. Junction boxes are an inexpensive (>$40) way to stay compliant.

Note how the manufacturer’s illustration is incorrect… maximum water level is the top of the coping unless there is an overflow line.

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