Total loss of battery power

[Odetymes]

I have a 2019 Ventana 3407 diesel and took it out for two days of dry camping. Unit was fully charged prior to leaving. First day no problems, second day used the generator a couple of times for a "boost". Following morning the ENTIRE coach AND engine batteries were dead. Overnight I did not use the heater or any other major electrical draws (that I know of). The only use was a CPAP machine, and a small bathroom nite light. The refrigerator was set at middle settings as usual and went on and off as normal. Prior to bedtime the gauges showed about 12.50 in power on both engine batteries and house. In the morning both batteries were at about 10.75/11.00. This was over an 8 hour nite time period.

I'm at a loss as to how/why this occurred. House and engine batteries are cleaned and well maintained (I thought). I'm home and have disconnected everything and will watch to see if batteries drain.

I'm more concerned as to how this happened and how to avoid. I will be getting all the batteries checked and certainly before any new dry camping trips! Any ideas and suggestions are most appreciated!

I'm now thinking of adding solar power which I know can be expensive. Thoughts on that are appreciated too!

Thanks

 

[sheridany]

that is odd your batteries went down that much overnight if you had that few devices on. How old are the Batteries? Do you have auto gen set up? That would help you avoid what happened. you definitely want to test the batteries as you stated.

 

[Odetymes]

that is odd your batteries went down that much overnight if you had that few devices on. How old are the Batteries? Do you have auto gen set up? That would help you avoid what happened. you definitely want to test the batteries as you stated.

Thanks for the suggestion. Batteries are three years old and used for dry camping about 5 times. I did have an occurrence about a year ago that I "forgot" to plug in to shore power when storing and they went house batteries went dead. I was told this was the beginning of the demise of the batteries as they should never be allowed to go that dead. I will have them checked and honestly I'm not aware of an auto gen on my coach but I"ll look.

 

[sheridany]

Here’s the manual.

Magnum Inverter Manual (2812)

Neal submitted a new resource: Magnum Inverter Manual (2812) - Magnum Inverter Manual Magnum Inverter Manual Read more about this resource...

rvforums.com

 

[NWIP]

Are your batteries AGM or flooded? If flooded, are any of the cells dry? I would certainly have the batteries loaded tested and they may need replacement.

 

[CaptainGizmo]

A few thoughts…

First, you’re batteries weren’t “dead” per se; they were just below the level for the inverter’s LVCO (low voltage cut off). To protect the batteries from further drain and damage the inverter panels are usually set around 10.9v.

Second, if you had BOTH sets drain equally, then it would indicate your batteries were merged, whether manually or automatically.

Battleries that are 3 years old should still have capacity and resiliency; assuming they are good quality AGM 8D models.

Now, as to the actual event. Actually, bringing your batteries up to 12.5 isn’t that much headroom to carry you through a day. Anytime I expect to “coast” on batteries, I need to assure they’re well topped off at 13.4v or better. There’s quite a bit of sag/rebound in battery voltage after being charged. You may see 12.5v on the panel, yet they could drop another half volt or so once they equalize. My Coach has a residential refer and the resting drain is around 5 Amp DC; there’s a lot of electronics and cooling fans that run 24/7. So, 12.5 doesn’t get me far.

Now, remember that the inverters may also be responsible for keeping the chassis set charger via the internal charger. So, it’s possible to have something drain the chassis batteries heavily, causing the inverter to kick its charger on and…this start to draw down the house set. But, aside from a short, or ignition circuit being active, not a lot on the chassis side to cause a big draw.

What would REALLY help you, is a Clamp Meter! This tool is insanely valuable for times like this and you’ll never be without one again. It’ll tell you EXACTLY how much current is being drawn AT THE BATTERY level!

Hope this helps you. Oh, here’s my video I made on the Clamp Meter..I guarantee you’ll love it! Check the Description for links on Amazon for all the items in the video.

 

[AbdRahim]

You likely have a larger battery bank, but bigger generator. It takes my generator all day to get the batteries from 12.0v to 12.8v. If I start out at 12.8, running nothing but a few lights (residential refer), They are down to 12.5 or so in the morning. I would never make it two days without running the generator for a long time.

 

[B & J T]

A few thoughts…

First, you’re batteries weren’t “dead” per se; they were just below the level for the inverter’s LVCO (low voltage cut off). To protect the batteries from further drain and damage the inverter panels are usually set around 10.9v.

Second, if you had BOTH sets drain equally, then it would indicate your batteries were merged, whether manually or automatically.

Battleries that are 3 years old should still have capacity and resiliency; assuming they are good quality AGM 8D models.

Now, as to the actual event. Actually, bringing your batteries up to 12.5 isn’t that much headroom to carry you through a day. Anytime I expect to “coast” on batteries, I need to assure they’re well topped off at 13.4v or better. There’s quite a bit of sag/rebound in battery voltage after being charged. You may see 12.5v on the panel, yet they could drop another half volt or so once they equalize. My Coach has a residential refer and the resting drain is around 5 Amp DC; there’s a lot of electronics and cooling fans that run 24/7. So, 12.5 doesn’t get me far.

Now, remember that the inverters may also be responsible for keeping the chassis set charger via the internal charger. So, it’s possible to have something drain the chassis batteries heavily, causing the inverter to kick its charger on and…this start to draw down the house set. But, aside from a short, or ignition circuit being active, not a lot on the chassis side to cause a big draw.

What would REALLY help you, is a Clamp Meter! This tool is insanely valuable for times like this and you’ll never be without one again. It’ll tell you EXACTLY how much current is being drawn AT THE BATTERY level!

Hope this helps you. Oh, here’s my video I made on the Clamp Meter..I guarantee you’ll love it! Check the Description for links on Amazon for all the items in the video.

Steve, thanks for the post and YouTube channel, I’m a subscriber! I’m anxious to view more of your videos, they look very informative and useful.

Now I’m on my way to Lowes to shop for a clamp style multimeter.

 

[Richpatty]

Keep us posted. My biggest concern is that BOTH sets of batteries are dead... With a properly operating(and wired) BIM, that should not happen...

Also, fully charged Lead acid batteries (while not being charged) after "resting" should read around 12.6 or 12.7, so your 12.5 was not too bad (assuming NOT being charged at that time).

 

[Odetymes]

Steve, thanks for the post and YouTube channel, I’m a subscriber! I’m anxious to view more of your videos, they look very informative and useful.

Now I’m on my way to Lowes to shop for a clamp style multimeter.

Thanks for the informative and helpful reply! Be assured I will be looking at the video too. I thank everyone for the quick replies and help and plan on checking the water levels again and of course, take the RV over to a professional that can help diagnose the problem. Again, thanks!