2. TANK PREPARATION
NOTE: it is important to keep all items dry during installation.
A) PRE-DRILLED TANKS.
Option 1: There may already be a 32mm pre-drilled opening in the tank top and possibly
a tube fitted. If so, remove the cover by undoing the two screws holding it in place, and
dispose of the tube in accordance with local government guidelines.
Option 2: There may already be a 2" threaded hole with a red cap screwed in to it If so
remove the red cap and disregard.
NB - Ensure the hole is a minimum DIAMETER 30mm.
Ensure that the space beneath the Watchman Sonic unit is free of any obstacles and
that the ultrasonic beam path is clear of obstructions. (See Picture 2)
B) UN-DRILLED TANKS
Where drilling is required to fit the transmitter, choose a flat level
point that is at the same level and no lower than any opening at
the top of the tank (filling point etc.) (See Picture 3)
WARNING: If you are unsure if you should drill a tank please
check with the tank manufacturer first.
The Transmitter can't sit at an angle as this gives an incorrect
level reading on the receiver. Take care not to choose an area
on which water could gather i.e. a dent/depression or a position
directly above any restricted area inside the tank. (See Picture 4)
NB: For tanks with window corrugations or internal braces ensure
that the Watchman Sonic Advanced is not positioned above or
within 15cm of the area of the WINDOW or the edge of the tank.
If the Watchman Sonic Advanced is positioned over or close to the
WINDOWED area it transmits incorrect readings to the receiver. (See
Picture 5) Ensure that the sonic path is clear to the bottom of
the tank as per pic 2. When installed incorrectly on some windowed
tanks the unit can experience false alarms as the oil level drops. It is
important to ensure that the unit is positioned so that the ultrasonic
beam has a 30cm diameter clear area to the bottom of the tank.
Positioning the unit too close to the tank wall or near a tank window
may cause false alarms.
Drill a hole in the place that you have selected on the tank's top
surface using a 32mm hole-saw. (shown in Picture 6)
Warning: If you are unsure if you should drill the tank please check
with the tank manufacturer first.
3. FITTING TRANSMITTER BASE (ONLY IF SUPPLIED)
For tanks with pre-drilled holes. Ensure guidelines from points 5 & 6 are adhered to.
• Remove cap from the hole (Picture 7) and insert
transmitter base, ensuring the weather seal is securely
in place (Picture 8 & 9).
• Tighten the Watchman Sonic Advanced base (Part E) on to
the tank with 2 stainless steel self-tapping, counter sunkscrews
supplied (Part C). Do not over tighten!
Sonic Advanced Transmitter
30cm
Choose a suitable position for transmitter
Outlet
Tank Braces
Tank Windows
Sonic
Transmitter
Pic 7
Pic 8
30cm
2
Pic
Outlet
3
Pic
4
Pic
5
Pic
Pic 6
Sonic
Transmitter
Pic 9
30cm
30cm
3
T