8.0 Using a BMK
77
© 2020 Sensata Technologies
8.1.1.2 Changing the Charge Ef
fi
ciency Setting
The factory default charge ef
fi
ciency setting is
Auto
. This setting allows the
battery monitor to automatically calculate variables that affect the charging
ef
fi
ciency, such as battery type, battery age, and how the batteries are
maintained—which is not always constant. With the
Auto
setting, the ef
fi
ciency
is automatically recalculated each time the batteries reach a 100% state of
charge (SOC).
The charge ef
fi
ciency setting can also be set to a
fi
xed value from 50% to 99%
if the battery’s charge ef
fi
ciency is known. With a setting other than
Auto
,
the battery monitor uses the
fi
xed setting to calculate the
AH I/O
display,
under the
03 BM: Meters
menu. For example, if you set the charge ef
fi
ciency
to 90% and 100 AH are removed from the battery, the
AH I/O
display would
read
000
only after 111 AH have been returned to the battery.
CAUTION:
The factory default charge ef
fi
ciency setting is
Auto
,
which allows the charging ef
fi
ciency to be automatically calculated.
In most circumstances, this setting determines the best charge
ef
fi
ciency. If you do not know your battery’s charging ef
fi
ciency,
leave it at the factory default setting (Auto). If the setting is
adjusted to a
fi
xed value, but this value is not correct, the state-of-
charge information will become more inaccurate with every charge.
To access the
AH I/O
display:
Press the METER button, then turn the
SELECT knob until the
03 BM: Meters
menu appears, press the SELECT knob
again, and then turn the SELECT knob to the
AH I/O
display.
After several charge/discharge cycles (below 80% SOC), the
AH I/O
reading
should be slightly positive when the
02 BM:
SOC
Batt SOC
display reads
99%
.
To view the
Batt SOC
display:
Press the METER button, then turn the
SELECT knob until the
02 BM: SOC
menu appears. If the
AH I/O
reading
is below 000 (negative#) when the
Batt SOC
display reads
99%
, then
increase the charge ef
fi
ciency setting. If you
fi
nd that the
AH I/O
reading
is substantially above zero when
Batt SOC
reads
99%
, then decrease the
charge ef
fi
ciency setting.
press to
save
rotate to
desired
selection:
.......
Stat us...
Chg Eff=Auto
Stat us...
Chg Eff= 50%
Stat us...
Chg Eff= 60%
Stat us...
Chg Eff= 97%
Status...
05 BM: Setup
From the
following menu:
press the
SELECT knob
Status...
BM Charge Eff
From the
following menu:
press the
SELECT knob
Figure 8-2, Changing the Charge Effi ciency Setting
