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Bad batteries and Inverter problems

December 31, 2017, 07:15:40 pm

 Got some bad news this week.MH is in shop for service issues and I'm told I have no 12 volt power, my Xantrex Inverter is showing faults and errors, is not charging house batteries and the Lifeline batteries are not holding a charge at all. The Lifelines are 51/2 years old and according to RV shop are basically dead. The RV dealer is a reputable dealer in Class A motorhomes here in So. Cal. They suggested a Magnum 2812 Inverter and MK  AGM Batteries, not Lifelines.  They said the MKs are a little less money than Lifelines, but what difference  does it make , It's a motorhome, everything is expensive. My coach is a 2002 40ft u320 and I have always seemed to have battery problems. Hope this combo of Magnum and MKs will be the answer of NO PROBLEMS ANYMORE!!!
ANY THOUGHTS>
Ralph in San Pedro

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Re: Bad batteries and Inverter problems

Reply #1 – December 31, 2017, 07:21:50 pm

We've had a Magnum MS2812 for about two years, and have been very happy with it in all respects.  Make sure it is properly programed for the type of battery you end up with.

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Re: Bad batteries and Inverter problems

Reply #2 – December 31, 2017, 07:52:41 pm

It may be that you need both a new inverter/charger AND new batteries-- any battery that is really deeply discharged is in harms way.

But, I would suggest using a supplemental charger to bring batteries back up.  Then see if the inverter/charger is working (proper charge voltage). And, once batteries fully charged, load test them.

Any other way of doing it is guessing (their guess, your money).

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Re: Bad batteries and Inverter problems

Reply #3 – December 31, 2017, 08:00:45 pm

Brett's suggestion is good.  Best to know where you really are before making changes.

Lots of folks use the Magnum.  They are good inverter/chargers. You might want to also look at the Victron MultiPlus 3000/12
Victron Phoenix 3000 VA Pure Sine Inverter

More efficient, higher peak power, cheaper, lighter weight, slightly smaller, wiring is easy, better warranty.  Just don't tell CaFlash. 

A Second House Battery Bank, Solar Panels, 2 New Inverters

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Re: Bad batteries and Inverter problems

Reply #4 – December 31, 2017, 09:30:09 pm

I am a happy victron user also. You can go wrong with the ease of use and versatility of product

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Re: Bad batteries and Inverter problems

Reply #5 – January 01, 2018, 08:45:13 pm

Off-topic discussion was split and moved to Fire Ring.

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Re: Bad batteries and Inverter problems

Reply #6 – January 01, 2018, 08:53:30 pm

Thanks

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Re: Bad batteries and Inverter problems

Reply #7 – January 10, 2018, 02:18:21 pm

Thanks for all the replies,. I will probably end up with a new Inverter/charger because that seems to be how the discharge of my batteries started. Magnum Inverter and MK AGM batteries.  Expensive, but have no choice, just want everything to work as it should.

Anyway thanks for the info.

Ralph

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Re: Bad batteries and Inverter problems

Reply #8 – January 10, 2018, 04:30:30 pm

Agree on the 2812 as it's 3,000 watt output should be a help to your coach.  Plus the 60 amp pass through.

According to mk's website the 8g8d's your coach came with new should give double the cycle life of their own AGM'S.

Do spring for the arc-50 magnum remote as it's float voltage is adjustable. 

What happens otherwise if plugged in is with the rc-50 remote the charger shuts off after a time on float then waits for the battery bank to drop to 12.5 volts before turning back on.  30%? Discharge? 

Unnecessarily cycling the battery banks.

The arc-50 can be programmed in its "favorites" mode on its left button to raise the voltage the charger kicks back in at after.

So battery stays in the higher 12 volt all the time.  Lessens the discharge/charge unnecessary battery cycling.


In constant use not a big thing but in storage should extend the battery banks life. 

My buddy does agree that the lifeline AGM'S if you decide on AGM'S are the best.

Charger needs to be set on AGM-2 as the magnum seems to be the only unit that has the higher charging voltage setting that the lifelines allow.

The magnum and the lifelines are a excellent match as the lifelines only seem among the AGM'S can and should  be equalized and that inverter does have an AGM equalize auto mode.

Probably why the lifelines gave you the 5 years as the older inverter probably did not have the higher charging voltage and the equalizer mode the lifelines may need for their longer life

Which would be a correct inverter for the original gel oem installation

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