Maximum Harbormaster User Manual
Harbormaster, Installation & operation instructions
INC.
30 Samuel Barnet Boulevard
New Bedford, Massachusetts 02745
(508) 995-2200 www.maximum-inc.com
HARBORMASTER
INSTALLATION & OPERATION
INSTRUCTIONS
INSTALLATION
Please follow this procedure before setting your tide clock. Use of our wall mounted panels or mantle
mounts is recommended but not necessary. Our panels are pre-drilled so that centering the instrument
is not a concern. Simply screw the two supplied right angle hangers into the two centrally located pilot
holes on either side of the large hole in the panel. These hangers should be screwed in so that there is
approximately a ½” of clearance left between the hanger and the panel.
On the back of your tide clock you will find 2 holes that will line up with the hangers. Align the holes and
hangers and push the clock against the panel. The clocks three rubber feet (not the rim of the brass
case) will now be resting on the panel. While still applying pressure against the rubber feet simply slide
the clock down so that it seats on the 2 hangers. If this feels too tight simply back the hangers off one
turn. If it feels too loose simply tighten the hangers one turn.
If you are not using one of our panels you can use the supplied template to spot the hanger holes on
your mounting surface. Using a #50 or 1/16” drill bit bore the two hanger holes into your mounting
surface. The installation instructions above will now apply as if you were using one of our panels.
Note: There is, by design, a small gap between the clock case flange and the mounting surface.
Do not mount the clock via the three screw holes located around the outer rim at the back of the
clock case. Compressing of the back-plate of the clock may cause improper operation and/or
permanent damage.
TIDE SETTING
Insert a standard AA 1.5 volt battery in the battery compartment observing proper polarity. Look at the
face and check that the round disc with the small hand at the center of the clock is rotating. This is the
“going indicator” and its sole purpose is for you to verify that the clock is operating. You are now ready to
set the Harbormaster. It is first necessary to determine the exact time of the high or low tide you wish to
set the clock to. This information is most easily found in a current tide table, either printed or on-line.
When reading a tide table, remember to allow for the difference (if any) between your exact location and
that of the reference location. Once you have determined when high or low tide is, simply set the clock
accordingly at that time using the thumbwheel on the clock mechanism just above the battery.
HOW A TIDE CLOCK WORKS
It has been known for centuries that up and down the east coast, tides occur approximately 50 minutes
later each day than they did the day before. The primary reason for this daily lag can be traced to the
moon. It takes the earth 24 hours to make one complete rotation in relation to the sun. This rotation is
called a “solar day”. It takes the moon 24 hours and 50 minutes to make one complete rotation around
the earth. This rotation is called a “lunar day”. It is the moon’s close proximity to us and the relatively
strong gravitational effect it has on the earth that causes the tides to follow the moon’s lunar schedule of
24 hours and 50 minutes per cycle.