Rev 6.3.0 12.09.16
PL Reference Manual
7
1
On the BOST and FLOT displays, the battery
voltage is shown. On the EQUL and ABSB
displays, the time on the equalisation or
absorption timer is displayed. When this time
gets up to the set time (ETIM or ATIM) the PL
will advance to the next state. Remember that
the timers will stop if the voltage falls below the
relevant set point.
1.2 Equalise (optional)
Many battery manufacturers recommend
that the battery bank be given an overcharge
occasionally. This is designed to equalise the
voltages and specific gravities of all the cells in
the bank by bringing them all up to full charge
and stirring up the electrolyte in the liquid cells
by gassing to reduce stratification.
The PL supports an automatic programmed
equalisation. This state allows the battery
voltage to rise until it gets to the equalisation
voltage EMAX if possible and then remain at this
voltage for the set equalisation time ETIM. This
equalisation is done every EFRQ days. (Typically
30-60 days). Equalisation will begin at 9am on the
appropriate day. If ETIM is 0, then equalisation
will not occur.
To prevent the controller being trapped in equalise
mode for a long time because there is inadequate
charge current to reach the equalise voltage, the PL
terminates equalise after 4 days.
1.3 ABSB (Absorption)
In this state, the PL tries to keep the battery
voltage constant while the last part of the battery
charging occurs. This prevents excessive gassing
which occurs at high cell voltages. The PL will
keep the battery voltage at the absorption
voltage ABSV until it has been at this voltage for
the absorption time ATIM. If there is a cloudy
period and there is insufficient charge current to
keep the voltage up to ABSV, then the absorption
timer will stop and resume when the voltage
comes back up to ABSV. When the absorption
time is finished, the PL advances to the Float
state.
1.4 FLOT (Float)
In this state, the battery has been fully charged.
The charge current is now used to keep the
battery voltage at a level which maintains full
charge. This voltage (FLTV) should be below the
gassing voltage to avoid excessive electrolyte
loss. If charge is drawn from the battery, the PL
will allow charging to resume until the battery
returns to FLTV.
