QUESTIONS AND ANSWERS
Q
Why is the screen of my BM1/BM2 blank?
A
Check the wiring is correct and securely terminated. Check the
fuse, and check that the battery is not completely flat.
Q
Why does my BM1/BM2 show that the number of hours
remaining is high or low when a constant discharge current is
flowing?.
A
The actual battery capacity is different from the value you have
entered in Engineering. The reasons for this difference have been
discussed above. Adjust the battery capacity in Engineering to
match the battery.
Q
My battery is made up of a bank of several batteries. Is that a
problem?
A
Not as long as the combination produces a nominal 12 volts, and
all the current drawn from the bank passes through the shunt.
Q
Can the BM1/BM2 monitor my engine starting battery as well
as my service battery?
A
Yes it can monitor the engine start battery voltage. The open
current voltage of the starter battery can be used to estimate its
state of charge
Q
I have another voltmeter on my boat which shows a different
value to the BM1/BM2 indication.
A
The BM1/BM2 very accurately measures the voltage directly
across the battery terminals. Other voltmeters may read
differently owing to volt drops in the boat's wiring.
Q
Why does my BM-1+ show a higher capacity immediately after
charging than it does after a few minutes' discharging?
A
This is an unavoidable feature of battery chemistry, which varies
from battery to battery, and the charging regime used.
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