HELP!: Battery Discharge When Nothing is Running

[Adammcc5]

Hello Everybody,

I recently hooked up Solar to my RV. This is the system below - (i added some fuses and what not as well as recommended)

Power Bright PW2300-12 Power Inverter 2300 Watt 12 Volt DC To 110 Volt AC

https://smile.amazon.com/gp/product/B002AMPGE6/ref=oh_aui_detailpage_o03_s02?ie=UTF8&psc=1

Renogy 300 Watts 12 Volts Monocrystalline Solar RV Kit with Adventurer

https://smile.amazon.com/gp/product/B015DFMTS2/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

12v 200ah Solar Power Battery - Deep Cycle

https://smile.amazon.com/gp/product/B00RPOI7F4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

When i first installed the system everything worked great. I was quickly charged up to 100% on my battery and everyday i would check in on the system it was full. I use a remote on my inverter to turn on power to external devices and then shut it off when i dont want it. The inverter remains on, but reports that nothing is drawing from it (there is a digital meter on it reporting in volts what is being drawn).

I decided recently to plug my shore power into the inverter. This runs a secondary inverter that comes stock with the camper van and some outlets that are strewn around. Nothing is plugged into them. When the shore power line is attached i still dont get any draw reported until something is powered (imagine that). Regardless, the inverter should shut off all power to external devices plugged into it when i flip the 'off' on the remote.

A few days after the van had shore power plugged in i went into the van and noticed that the charge controllers interface (its digital, not LED lights) was completely blank. I look at the inverter and the light is red signalling that it is not receiving its 10v to run. I run leads from a multimeter to the battery and nothing comes up. Im freaked out - this is all new equipment. I start the engine on the vehicle and everything starts back up. The inverter is still red lit - because the battery is way below voltage. Its reporting like ~10v on the charge controller interface. Its about 6pm and the sun is going down here in sunny san diego. I turn off the inverter completely and go inside for the night. I come out the next morning around 10am in bright sun and the whole system is dead again. I run the vehicle for a few minutes (car battery is never affected by solar setup) and everything starts again. This time the systems is extremely low. Even my LP gas monitor is reporting low voltage and beeping at me. Even thought the inverter is off, i remove all cables from it and let it sit in the sun. Bright sun all day today and the system has recovered to 12v and 14% charge. This seems very low according to my observations from when i bought the system. It had the ability to charge 14% in an hour previously. Its bright sun and no shade all day.

I'm concerned that the system is clearly drawing power (i dont know where or how). The charge controller and the inverter in standby should not be enough to exhaust a 300watt system on a 200ah battery. Not only that, but now im worried that whatever has happened as seriously damaged a brand new, and expensive battery.

Can anybody help me figure out what could be happening here. Its easy to assume that it has something to do with the shore power addition, but the inverter on standby should not be sending power to that line. For example, with shore power plugged in to the inverter the microwave doesnt turn on unless the inverter is switched 'on' to remote. I scowered the vehicle for anything that could be drawing power that i didnt notice, but it would have to be reported on the inverter in order for the solar battery to power it.

HELP! - I am nearing my date for taking this RV off grid for several months.

[Mike90250]

Sadly, you have been suckered. The parts you have are not balanced. With only 300W of panels, you should not use more than a 600 w inverter.
The standby losses of the 2300w inverter (230w) are likely more than your loads are. Large inverters are unsafe in low 12V systems, to deliver 2Kw, it needs to pull 166A from the battery, and can easily melt cables and start fires.
The generator in your van, can in half hour, produce more power than the 300W of panels can in a week,
And yes, your batteries are ruined. You might get them up to 14V eventually, but the deep discharge to 10V has ruined one of the internal cells (6, 2v cells =12V battery)

[Wy_White_Wolf]

...I decided recently to plug my shore power into the inverter. This runs a secondary inverter that comes stock with the camper van and some outlets that are strewn around. Nothing is plugged into them. When the shore power line is attached i still dont get any draw reported until something is powered (imagine that). Regardless, the inverter should shut off all power to external devices plugged into it when i flip the 'off' on the remote....

What?

Your inverter is not designed to work with grid power. It is either the inverter or shore power. You can not run both at the same time. Doing so will damage the inverter.

Do you have a transfer switch that isolates the inverter from the grid power?

WWW

[Adammcc5]

Sorry if my explanation is confusing. The RV comes with a shore power line - this line would normally be extended out of the camper to an on-grid power source so that you can run high energy appliances like the refrigerator, ac and microwave without pulling from your vehicle battery. All of these appliances go through a fused 'inveter' that takes the shore power and converts it for use on these appliances. I ran this power cord directly into my solar inverter. I now can access the vans internal outlets as well as power the microwave and other appliances that are plugged into the vans pre-installed outlets. I do not run the refrigerator or AC off of this power because it will drain the battery rapidly, but i could if i wanted to. Again though, i would have to turn the solar inverter to 'on' to allow these appliances to use the power from the solar setup. With it off, the battery still discharged the other day.

[littleharbor]

If your shore power system has an AC to DC converter, as most rv's do you shouldn't plug it into your stand alone inverter as doing this is causing your converter to charge your batteries with battery power. eventually you will kill your battery bank.

[ewarnerusa]

If your shore power system has an AC to DC converter, as most rv's do you shouldn't plug it into your stand alone inverter as doing this is causing your converter to charge your batteries with battery power. eventually you will kill your battery bank.

Actually, simply plugging the shore power cable into the inverter is a great way to supply AC to the entire camper when off-grid. This is exactly how we do it. But you are right, you MUST remove the converter from the system or it will behave as you said. I moved my converter's AC power supply wiring to its own dedicated AC breaker and use it like an on/off switch. Default is off because I don't often need a battery charge from shore power. Water heater and refrigerator should be put on gas so that they don't switch over to AC and draw down the batteries. I also flip breakers for the electric water heater, microwave, and air conditioner to off to avoid accidentally switching these appliances on and overloading the inverter. I'm having trouble following some of the OP's descriptions, but I sort of think he's done what you are describing. The converter was drawing AC load from the inverter which was drawing from the batteries.

OP - while your logic is correct that your inverter is powering the whole camper and supplying AC to the appliances, your 12V battery will not be up to the challenge of powering your air conditioner or microwave. Even if your inverter is installed properly (close to batteries with fat cables), it will pull so much DC current that you'll get a huge voltage drop from the battery which will cause the inverter to fault out due to low input voltage. Two of those monster 12V batteries you've linked to installed in parallel and then your microwave may work. 4 of them and maybe the air con would work, but your inverter may not be big enough to handle the start up surge.