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ETTING THE CHARGE EFFICIENCY
From ENG press V&A to get to the charge efficiency screen. The charge
efficiency is the ratio of charge you get out divided by the charge put in.
The default value is 95% which is typical of a LiFePO4 battery in good
condition.
VIEWING THE V(max) VOLTAGE
From ENG press V&A to get to the V(max) screen.
A LiFePO4 battery is usually charged from a substantially constant
current source until the terminal voltage rises to 14.4 volts V(max) at
which point the battery is within a few percent of being fully charged.
Maintaining this terminal voltage until the charge current falls to a low
level completes the charging process. V(max) cannot be adjusted from this
screen it is set using the semi-automatic approach as described in the
SYNCHRONISING section.
SYNCHRONISING
When the monitor is first installed it will show the voltage and charge or
discharge current of the service battery. The state of charge indicator will
flash on and off indicating that the system requires synchronising.
Synchronisation is the process by which the system establishes when the
battery is fully charged. The monitor then calculates the subsequent state
of charge by integrating the charge and discharge current over time. As
charging a LiFePO4 battery in excess of 14.4 volts reduces its life
expectancy some charging systems set V(max) a little lower. This has the
advantage of protecting the battery and extending its service life at the
expense of a small amount of available capacity. The BM-1Li indicates the
state of charge of available capacity. The available capacity will be slightly
less than the stated capacity if V(max) is less than 14.4 volts as the
charger cannot fully charge the battery.
If Vmax never reaches 14.4 volts (The default setting of Vmax) then
synchronisation cannot occur and the state of charge display will continue
to flash. Ensure that the battery is in a fully charged condition then press
and hold the SYNC key until the bar graph counts down to one bar and
release the key. This is the semi-automatic synchronisation process which
synchronises the monitor and automatically resets the value of V(max) in
engineering. Further synchronising should not be necessary unless power
