question

mrpogle avatar image

Tail current with LiFePo

300Ah LiFePo, 3KVA Multiplus, BMV712, MPPT 150/85, CCGX


The system is 8 weeks old and I have just noticed that the installer has set the tail current to 1%. The general recommendation seems to be 4%. The system has performed 8 syncs in the past 8 weeks. Should I increase the tail current setting?

BMV Battery MonitorLithium Batterybattery charging
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4 Answers
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boekel answered ·

how many times the batteries were fully charged in this time? (based on voltage, if you can see this, is the system online?)

(I'm assuming your talking about the battery monitor)

2% or 3% will probably work fine if the charged voltage is set correctly.


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mrpogle answered ·

Thanks. I have reduced the charge detection time to 3 mins and have had a sync within the hour. I'll see how this goes before increasing the tail current.

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mrpogle answered ·

Fully charged voltage is set to 13.5v and the time is set to 30 mins. The batteries (3x100AH) spend most of their time at 13.5v as we have shore-power all the time and we are only using the batteries for Power Assist.

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gmiller answered ·

I have mine set at 1% (4A on my 400Ah LiFePo4 set up) as suggested by a Lithium "guru" from South Australia. He also suggested 13.9V as the "Charged Voltage" setting. Charged detection time set at 1 minute.

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