[RE-wrenches] Magnum: meter won't reset; Internal Bridge error

[boB Gudgel]

Mark,
Does this customer have another charging source besides a generator, 
like PV  ?   That last few percent SOC
into the batteries is very inefficient of course.  If they are  starting 
to charge their batteries only when the inverter cuts
out due to under-voltage cut out, it may be that they have more of a 
problem than getting that last 1% into the
bank ?   Even if it's charged to anywhere ~near~ 99%, the bank is 
running down pretty low (less than 50% SOC anyway)

OK, so the BMK (Magnum's battery monitor),  uses 3 criteria which must 
all be met before it will give you that
last 1% State Of Charge....

1) The return Amps must go below 2% of the Amp-Hour setting for the 
battery bank (settings via the remote).

2)  Battery voltage Vs. Time...  The battery voltage must remain at a 
voltage for a certain amount of time.
    The lower the battery voltage, the longer this time it must remain 
there. .As long as criteria 1 and 3 are met,
    say, if you were in Float (~13.5V per 12V battery), that time is 
around 10 minutes.

3) The Amp-Hours IN-to the battery must be within 1% of the A-H that 
came OUT.

I am assured (from Magnum) that when it reads 99% SOC it is at ~least~  
99% SOC.

As for the bridge fault error, It may or may not be an actual problem.  
There has been (as I thought) a software fix in case it
is a nuisance message, that did plague a few of the earlier MS4448AE units.

This all being said, I have included (below) an email I received from 
Glen Darby, one of our customer service guys downstairs.

Have a day and 1/2  !
boB Gudgel



Bob,
Your question

(1) Magnum's integrated battery monitor hasn't done a 100% reset for some
 > time. It counts up to 99%, no more Is this an equipment glitch? OR: 
should we fool the system into repeating the
 > bulk charge to try again for the reset?

I would try setting the total amp hrs a little lower and do a reset.

2) The client reports an "Internal Bridge" fault.

This is not normal and if this fault comes back again, the customer 
should call our tech
support (425-353-8833) at the time it is in a fault mode so we can 
trouble shoot the unit.
The Internal Bridge fault means that the unit senses no ac output 
voltage or current when
it senses voltage on the input. It shuts down to protect the fets.  This 
should not be
caused by the low DCV.

Thank you

(Glen)


boB wrote:
> mick abraham wrote:
>> Greetings, all~
>>
>> If there is no Magnum employee monitoring the Wrench List, could boB 
>> Gudgel forward this as appropriate?
>>
>> My client has a "genset plus" system--no recharge other than his 
>> MagnaSine
>> 4448AE driven by a generator. Batteries are a single string of Deka 
>> 8L-16's, a
>> few months old. We're running the charger defaults: 48 amp maximum 
>> charge
>> rate, 2 hour absorption, and flooded setpoints.
>>
>> (1) Magnum's integrated battery monitor hasn't done a 100% reset for 
>> some
>> time. It counts up to 99%, no more, according to the report from my 
>> customer.
>> I asked the customer to run the generator for longer than his normal 
>> pattern,
>> in order to force the meter to reset (and also to increase battery 
>> SOC). The
>> "AH I/O" counter ran up to about 78 amp hours above zero and the
>> inverter/charger went into float for over an hour...but still we got 
>> no reset
>> on the counters.
>> Is this an equipment glitch? OR: should we fool the system into 
>> repeating the
>> bulk charge to try again for the reset?
>> (2) The client reports an "Internal Bridge" fault. This has happened 
>> multiple
>> times because the customer has become adept at resetting the unit per 
>> page 36
>> of the manual. The manual says nothing about "internal bridge", but 
>> repeated
>> shutdowns seem non-normal to me. I do notice something in the manual 
>> about the
>> "FET Bridge" so maybe that's where the trouble is.
>> The customer has been pounding their batteries by driving the 
>> inverter until
>> it shuts down due to low battery voltage. Could that trigger the 
>> "Internal
>> Bridge" fault? It certainly triggers my cringe reflex...
>>
>> If we can get the percentage meter back on track, that might help 
>> reduce the
>> customer's "drive until it dies" behavior. Here's hoping...
>>
>> Thankx,
>>
>> Mick Abraham, Proprietor
>> www.abrahamsolar.com
>> Voice: 970-731-4675
>>   
>
> No problem, Mark.   Your info is being forwarded to the Magnum 
> Engineering department now and I will follow up
> on this when I get in tomorrow morning.  The 99% (BMK) issue is 
> familiar but I can't remember off hand exactly what the
> solution is.  I believe  the internal bridge fault (inverter), was on 
> earlier units and has a software fix  as I remember.
> You should get more info hopefully tomorrow.
>
> Thanks,
> boB
>
> .
>

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