[RE-wrenches] Magnum inverter with LFP batteries

[Zeke Yewdall]

I have done a few upgrades with Magnum inverters on newer LFP batteries
(EG4 LL series if they are a 12 or 24 volt magnum, various ones Midnite and
Eclipse and ReLion for 48 volt magnums).   The newer magnums (not sure
exact date or firmware number) seem to be okay, other than LVD not really
being adjustable high enough to function with an 8 or 16 cell LFP -- can
work with a 15 cell LFP on 48 volts).  I have heard that the older magnums
just will not charge properly, as a few other folks here have described.

I always try to have a BMK do SOC based generator control if using lithium,
as voltage is very hard to get decent control with.  But... make sure you
get to recalibration settings for the BMS on the lithium batteries
regularly, as SOC will drift over several weeks of low SOC cycling and be
massively out of reality... I've seen it drift 1 or 2% a day, which isn't
much if you get back to 100% each day, but is ALOT if you keep doing this
for 3 or 4 weeks... like 50% different than reality...  Best practice would
be a SOC control for generator starting with a voltage catch as a backup in
case SOC drifts.

I have not heard that Victron has any intention of introducing a split
phase unit.  The US market is just not a big enough part of their worldwide
sales it seems, and to them the ability to stack two 120 volt units in
series solves this problem.  You can also use a 230 volt EU unit set to
60Hz, and with an autotransformer to synthesize the neutral.  Not UL listed
that way, but it's another way to get 120/240 split phase from a single
inverter for off grid use (not as useable on grid, as then you have to
synthesize the neutral on both the input and output and the two neutrals
are not exactly the same potential, so you end up having to run an isolated
neutral on the backed up loads, which introduces even more code issues...
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