Deep-SeaLite®
User
Manual
6/19/02
4
4.
Electrical and Thermal Warnings
It is essential that caution is exercised whenever electricity is utilized in or near the water. AC
current is certainly more dangerous, but even 12 volts DC can pose an electrocution hazard
under certain circumstances.
A Ground Fault Interrupt should be used whenever high
voltage lights are being utilized; when divers are in the water this is especially critical! Do
not operate AC-powered lights without a GFI!
Additionally, all high voltage lights should be
case grounded for safety. If a protective glass dome is broken and the light floods, a short circuit
will likely occur. The current will flow to the ground reference; if the body of the light is
grounded, then the short circuit will occur between the "hot" lead and the body of the light rather
than the water surrounding the light.
It is also important not to burn a light in air for more than a few seconds unless that light has
been specifically designed for this purpose. Most lights become quite hot under normal
operation and rely on the surrouding water to provide cooling. When an underwater light is
burned in air, the resulting heat buildup can pose a fire hazard. If the light is operated for testing
purposes in air, be sure to let it cool down for a couple of minutes before immersing it in water.
It is also a good idea to turn the light off a few seconds prior to removing it from the water.
These precautions minimize the thermal shock on the pyrex dome; thermal shock is a rapid
change in temperature which can cause the pyrex to crack. If a certain application requires the
light to be operated in a wet/dry environment, DSPL recommends using lamps of 100 watts or
less. Extreme caution must be used when handling lights burning in air due to the high operating
temperatures.
