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Topic: Mystery Battery Load (Read 708 times) previous topic - next topic

Mystery Battery Load

We parked our MH for about a week to unload, clean it up, before putting in storage for a while. I had the gen set on auto start. Within a day, with NOTHING in the coach on: no refrig, no microwave oven, no radio.....only the co2 alarm and fire alarms, the generator would come on about every two hours for just a short period of time.
I have recently parked the MH in a nearby garage. I left it unplugged, for about 4 days, again, with no loads. When I returned today, the Magnum ME-RC showed very low battery!!!!????
I was fortunate to plug it into a nearby outlet, to keep the batteries charged. I have been reading the Magnum owners manual ( still have LOTS of questions ), and would search past posts, but I don't know what to search for. ANY ideas of what could be draining our batteries?? When not plugged to land line, and set to auto gen, what should be the setting be for the auto start on the Magnum?
This area of expertise is not my strength. Thanks

Re: Mystery Battery Load

Reply #1 –
My 2KW inverter / charger uses 30 watts doing nothing, add the other vampires above plus the gas solenoid, which uses 8 watts. Over four days, that could be about 100 watts times 96 hours, or 9600 watt hours. That would surely kill even my 9200 watt hour lithium battery.

Shut the inverter down, disconnect your 12v batteries and put a battery maintainer or solar charger on your batteries.

Re: Mystery Battery Load

Reply #2 –
Quote from: GleamB –
When not plugged to land line, and set to auto gen, what should be the setting be for the auto start on the Magnum?
The instructions for setup of the ME-AGS-N module are found in the Owner's Manual for the ME-RC Remote Control Display.  I don't have the add-on generator start module in our coach, so I'm no help.  I just skimmed through the 15 pages of instructions, and they are a bit complicated.  Not something anybody will be able to tell you in a couple posts on this Forum...at least in my opinion.

Two options.  Either plow through the owner's manual and decipher the instructions by yourself, or find someone who is familiar with the system and who will assist you with the setup.  Wish I could be more helpful!  Good luck.

Re: Mystery Battery Load

Reply #3 –
What shape are the batteries in?

Re: Mystery Battery Load

Reply #4 –
Auto start should have kept the batteries up and with nothing on it should last a couple days. I would check the batteries and also the set point for the auto start voltage. 

Re: Mystery Battery Load

Reply #5 –
Thanks for the info....will do the above !!

Re: Mystery Battery Load

Reply #6 –
Sounds like you might need some new batteries!  All it takes one or two small mistakes and bad timing (read: right before putting into storage), to run down a set of batteries to the point of permanent damage.  Some would advise that they put new batteries in every coach they buy.

Nothing wrong with doing a few tests with those batteries first before you go shelling out the $.


Let's say you have a 400 Amp Hour battery - so you have 200 usable AHs.  When you have exhuasted those 200 AHs, your battery should at about 50% charge, in the 12V-12.2V range.  To test: Fully charge the batteries, unplug, and turn on one light - 15 minutes or so after unplugging they should read about 13-13.2 V  (Assuming you have AGMs).  Turn on everything, use your display to guide you, and try to get as close to a 50 amp load going as you can.  Let it all run for 2 hours (to use 100 AHs), and then turn it all off and let the batteries rest for 10-15 minutes before taking another reading..  At the end of 2 hours, you should be pretty close to 75% battery, somewhere in the 12.5-12.6 Volt neighborhood.  If you are much lower - you have at least one bad battery.  If you suspect something is wrong but that test isn't definitive (or if you don't want to mess with it in the first place) you can call somebody out to coach to run a load test on the batteries. For a fee, of course.

Re: Mystery Battery Load

Reply #7 –
I am just now "plowing" through my AGS-N manual for installing it to control a Generac ECO15 as back up to my one year old solar system for house and barn (motorhome storage).  The Magnum components do work well together.  However, they seem designed to cover all types of systems.  Therefore, much "editing" is demanded to address only information pertaining to your condition.  (Such as the temperature sensor and the capability to start a generator upon a selected temperature being sensed, as in a motorhome, does not apply for me.)

One of the reasons I chose the Generac ECO was because it is designed to do the job for which I intend to use it.  It is not a "standby" generator.  It is much simpler to wire to my system than other generators.  (This opinion is 'generated' as I read and re-read the AGS-N manual and what is involved to connect other brands of generators.)  I wonder if your AGS is correctly wired to start your generator....

Also consider the state of your batteries.  Batteries die mainly because they have been consistently undercharged.  Recently I have begun a program to desulfate the AGMs on my motorhome.  (I have chosen to use AGMs because I consider them to handle cold weather better than other types of batteries.)  I had always followed the "rules" and never given AGMs any Equalization over-voltage sessions.  But I read somewhere (perhaps this forum) that AGMs can-and-should be Equalized 1hour for each 100-Ah capacity.  This has improved my three-year old AGMs on my motorhome.  I am pleased to have learned this.  My batteries now hold a charge much longer than before when I never equalized.

andy1
 

Re: Mystery Battery Load

Reply #8 –
Quote from: Lewis Anderson –
I had always followed the "rules" and never given AGMs any Equalization over-voltage sessions.  But I read somewhere (perhaps this forum) that AGMs can-and-should be Equalized 1hour for each 100-Ah capacity.  This has improved my three-year old AGMs on my motorhome.  I am pleased to have learned this.  My batteries now hold a charge much longer than before when I never equalized.
andy1
Andy,
Love our AGMs and wanted to do just than but in going to the manufacturer's site, they warned against equalization. Guess it varies from brand to brand.

Pierce