DAVIS Mega-Light Masthead - Manual

Instructions for Mega-Light™ Masthead #3310
#3310 Mega-Light™ Masthead comes attached to a stainless steel bracket with a 12" (30.5 cm)
wire lead for connection to any 12-volt system. The bracket is drilled with several installation
holes, offering many options for attachment to a mast, wall or bulkhead. In addition to these
unique features, Mega-Light Masthead offers:
• Two easy-to-change bulbs for low current draw or extra brightness. The low current bulb draws
just 0.11 amps at 12 volts. The extra bright bulb draws 0.32 amps.
• Visibility up to 2 nautical miles (3.7 KM).
• Photo cell for automatic operation; switches on at night and off at dawn.
• Approximately 1 amp consumed all night long.
• Bright bulb lasts 7,500 hours. Davis #3330, Mega-Light Replacement Bulb Kit, provides an
extra bright and low current bulb.
Electrical Connections
The wire lead from the lamp must be fused using a 1 amp in-line fuse (not included). Wire as
small 22 gauge can be run for over 200' (60 meters) from the light to the 12-volt source. All con-
nections must be soldered and sealed to protect both the circuit and the connections from expo-
sure. A small section of heat shrink tubing is provided to protect the wire splice at the 12" (30.5
cm) pig tail lead. Simply apply heat and hold the shrink tube in place; the tubing will shrink tightly
around the wire, covering the soldered connection. An on-off master switch may be added any-
where in-line.
Mechanical Installation
For mounting your Mega-Light on a
wall or bulkhead, the use of two #10
(4 mm) fasteners should be accept-
able. Note that these slots are
designed to allow the light to mount
right side up or upside down. For mast
mounting, use at least four #10 (4 mm)
stainless steel fasteners. Drilling and
tapping the holes for machine screws is
the most secure and preferred way to
install the light. In all cases, use proper
bedding compound such as silicone
seal or an anti-seize compound.
Please consult a professional
installer if you do not understand
how to do it yourself.
UL approved
Strain Relief
Stainless Steel
Bracket
Mounting Holes
in Bracket
12" (30.5 cm)
Lead Wire
to 12 Volt Source
Slotted Key Way
Hole (2)
#10 Holes (6)
1:1 lens
on end of light
for area lighting
Light Sensor
switches on and off
automatically
5000+ Hour Bulb
(replaceable)
Fresnel Lens
for visibility up to
2 nautical miles (3.7 km)
Mounting Hole
for Windex ®
Wind Indicator
3465 Diablo Avenue, Hayward, CA 94545, U.S.A.
Phone (510) 732-9229 • Fax (510) 732-9188
[email protected] • www.davisnet.com
3310_Eng.pdf October 2005
Replacement Parts
Contact your dealer or Davis Instruments to order parts.
3330 Spare Bulbs: extra bright bulb and
super low current bulb
R3310A Replacement Bracket, stainless steel
R3300C Spare Lens