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The BWT watering plug assembly – plug, float and gasket (see Figure 1) – is
the heart of the system. It controls the watering of each battery cell to the
recommended shut-off level. This is a minimum of 1/8“ below the vent well at
the end of recharge.
During watering, the rising electrolyte level causes the float to rise. As the
float rises, a self-contained mechanical linkage closes a poppet valve inside
the plug. Once closed, system pressure keeps the valve closed for the
duration of the filling cycle. The installed system is designed to bleed off this
pressure gradually once the quick-disconnect is disconnected.
During watering, the water flows from the filter/regulator unit or tank unit,
through the visual flow indicator (water wheel), quick-disconnect coupler, in–
line filter, and in to the plugs.
SYSTEM REQUIREMENTS
a)
Filtration:
The supply water should be filtered to ensure proper long-term operation. Experience
has shown that municipal water supplies typically contain unacceptable amounts of particles
and debris. A 20-micron (or finer) filter is recommended.
NOTE: This is in addition to the auxiliary 100-micron BWT filter pre-
packed with the system.
b)
Pressure:
Minimum height of water reservoir must be ten
feet. For municipal water supply lines, a pressure regulator
is required. Recomended static system pressure is 15 psi.
Excessive pressure can cause plugs to snap shut prematurely.
Insufficient pressure will cause the cells to fill more slowly.
c)
Fill Time:
The filling system should only be connected long
enough for the cells to fill (usually 1 to 3 minutes). When the
flow indicator stops spinning, the cells are full and the quick-
disconnect should be disconnected.
CAUTION: For systems where a timer control is used, BFS recommends
filling for two minutes.
d)
Float Clearance:
Adequate clearance (T1), per Figure 2a/b/c is
required for proper action.
e)
Water Quality:
Use only water that meets the following analysis:
Total solids
less than 125 ppm
Fixed solids
less than 75 ppm
Organic and volatile material
less than 50 ppm
Iron
less
than
4
ppm
Figure 1
Figure 2a
T1
Figure 2b
T2
Figure 2c
Top of separators
or moss guard
Electrolyte level
clearance
5mm
