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9.
Troubleshooting and Q&A
1.
Why is the battery bank suddenly shutting off?
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Possible Cause 1:
It is likely that one or more of your batteries are not truly at the same state of charge as the
others. Those batteries are hitting the upper or lower voltage limits ahead of the others and
the BMS is shutting them down. To ensure that the batteries don't unexpectedly shutdown
they all must be charged to (or discharged) to the exact same voltage. That voltage must lie
either on the upper end of the charge curve where it flares up (green circle – upper right) or
the lower end (yellow circle – lower left) as shown in Figure 3.
Figure 4: Voltage v. Charge Limits
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Solution:
The batteries must be individually charged to the same voltage at the part of the LiFePO4
charging curve where either the voltage quickly swings up (between 13.8V-14.4V, circled in
green in the graph below) or, less preferably, discharged to where the voltage quickly drops off
(between 11.5-12.5V circled in yellow below). Consider using a simple 12V AC charger but it
must be able to achieve 14.0-14.4V. Use a multimeter or voltmeter to ensure that once the
batteries are fully charged they are all at the same voltage.
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Possible Cause 2:
Your load (i.e. inverter or DC load) has exceeded the current capabilities of the batteries.
KiloVault® batteries are capable of handling 150A continuous, and for a very brief moment
handle up to 500A for a surge load. If your load is known to be close to 150A continuous or
has a couple of very high surge loads (e.g. pumps, AC/HVAC systems, etc.) it is possible that the
load is simply too high for the bank.
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Solution: