Specifications

From the flow meter, the product water enters a chamber called the "salinity cell" where
two probes measure the electrical resistance of the product water. The residual ion content
of the product water is inversely proportional to its electrical resistance, totally de-ionized
having infinite resistance. Typical resistance of the product water will be in the
neighborhood of 1500 ohms. The purity of the product water may also be expressed in
mhos where the value would be the reciprocal of that in ohms. Additionally, the purity may
be expressed as parts per million of total dissolved solids. The PPM value (at levels found
in product water) is roughly half of the value in micro-mhos.
If the salinity cell and associated circuitry determines that the product water is of
acceptable quality, an electric "diversion" valve is opened and the product water is allowed
to flow into whatever storage facilities are provided. Should the vacuum at the inlet of the
high pressure pump become abnormally great due to clogged pre-filters or some other
cause, an automatic circuit will stop the system and activate a "HIGH INLET VACUUM" light.
RO pressure is indicated on the RO pressure gauge. Pressure in excess of 1000 PSI will
trigger the pressure relief valve.
Central Processing Module (CPM)
The Central Processing Module is equipped with the system control switch, start button
and all annunciator lamps. As will as the product water flow meter, salinity probe (MPU) in
which water quality is measured, and the electric diversion valve (Burkheart valve) which
directs potable product water into the storage tanks. The front of the CPM forms the
system's main control panel.
Pre-Filtration Module
The Pre-Filtration Module is a three-stage filter system that removes suspended particulate
matter from the incoming feed-water. Efficient pre-filtration contributes greatly to
prolonging RO membrane life. The first stage consists SS strainer screen (Plankton filter)
housed in a clear plastic bowl. The second stage is a 577 square inch, pleated-paper 50-
micron filter. The third stage is a 5-micron filtration cartridge.
The SS strainer screen (Stage 1) can be cleaned and reused over again. The 50 and 5-
micron cartridges should be replaced as needed. You may want to save the best of the
used, 5-micron filters for the cleaning process. A relay module mounted on the pre-filter
assembly operates the electric clutch at the feedwater (Cat) pump and the pre feed pump
(water puppy). The primary system fuse and over-ride switch used when performing the
cleaning and preserving tasks, as well as terminal strips for convenient wiring are also
mounted on this relay module.
Reverse Osmosis Module (ROM)
The Reverse Osmosis Module is where de-ionization takes place. Feed-water (seawater)
under pressure flows out the high-pressure pump module and through the ROM high-
pressure vessel past the reverse osmosis membrane inside the pressure vessel. Pure
water molecules permeate through the membrane fabric where they are collected and
manifold to a tube in the center of the membrane.
This "product water" then flows back into the Central Processing Module for further
processing. Meanwhile, the feed-water that did not permeate through the membrane flows
to the Pressure Regulator Module and is subsequently discharged as waste overboard.
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