New drain issue.

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Markw

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So in the last several days I have noticed that, for some reason, my battery charge isn't lasting as long as it used to. In fact, it's lasting maybe 2/3rds as long as it was even a week ago.

I haven't added any additional drains on the system recently nor have I changed the wiring since a couple weeks ago when I added two power ports because the power port I had previously blew out.

I do have an instant pot, but I only use it during the day when the solar panels will recharge the battery before the sun goes down.

My power system:

300 watts of solar on the roof
100 AH Ampere Time battery that I have been using for less than a year.
30 amp Epever MPPT charge controller
12v fuse block
1200 watt GoPower Inverter

Drains:

Laptop (same one I have been using since before I became a Nomad).
12v fridge (same one I have been using the whole time)
Phone
3 qt Instant Pot (that I only use during the day)
12v kettle
USB rechargeable water pump that sits on top of the water bottles.

It hasn't been hotter than before, in fact the temp has been fairly cool in the evenings so the fridge isn't running more than it was before and the inverter fans aren't either.

So I don't get why the charge is draining faster than it was.
 
Let's Troubleshoot the system..............

You have a battery monitor and the Charge Controller display.........Do they indicate anything "Different"

Check MY connections.........TIGHT (not gorilla).......Batteries Fuses Junctions.........any discoloration....anything Warm ?

Check YOUR connections.....Are the wires big enough.....tight enough......Is it a Quality power port ?

Maybe turn OFF the Inverter for a while............give it a chance to catch-up........GAS for the stove!
 
I suspect the battery is probably not being charged fully everyday. Do you have a coulombcounter for your 100ah battery?
First thing I would check is to make sure the battery terminals are at least getting up to 14.4 volts during the day. Checking the voltage directly from the battery terminals is the only way to make sure there is no voltage drop from controller to the battery.
 
Let's Troubleshoot the system..............

You have a battery monitor and the Charge Controller display.........Do they indicate anything "Different"

Check MY connections.........TIGHT (not gorilla).......Batteries Fuses Junctions.........any discoloration....anything Warm ?

Check YOUR connections.....Are the wires big enough.....tight enough......Is it a Quality power port ?

Maybe turn OFF the Inverter for a while............give it a chance to catch-up........GAS for the stove!
Definite discoloration on the cable right after the top fuse.
 
The bms should be OK, it won't cause any draining of the battery. You mention the weather is hot, the fridge running more than usual.
About 3 years ago in very hot weather with the fridge running more, having to run 2 swampcoolers to stay cool and also my roof vent, after about 2 weeks my 240 watt panel was no longer keeping up with all the power use, it drained the 220ah lifepo4 to zero percent. It happens slowly but once its at zero percent its game over.
Once the battery is drained to zero it takes weeks to get it back up to 100 percent if I only charge it with solar, and thats if I disconnect the fridge and use minimal power every day.
What is the max amps your solar charge controller is putting out? that will give you an idea if your going to get the battery charged up. You have to be charging at the minimum of 10 amps in full sunlight.
 
During the brightest part of the day it's generally between 15 and 20 amps. RIght now (about1:30 in the afternoon on a pretty sunny day) it's at 15.6amps, but the charge doesn't seem to be going above 13.6 or maybe 13.8 volts when it should go up to 14.4. Which is why I think there may be an issue with the battery.

Where I currently am (just outside Flagstaff) it gets a bit warm, but nothing like Pahrump or Quartzsite. According to my phone it's currently 72 degrees here, but I've seen go to 85ish.

As for the controller, it's an Epever 100/30 MPPT and I have 300 watts on the roof.
 
I can't see one 100AH battery keeping up with the load. the laptop charger draws more than you think.
Might consider adding another battery for more storage. The charging hours are already getting shorter for the year and it will only get worst.
You probably do this already but turn everything off like the inverter when not in use. It all counts on the drain
 
The charge amps are good, I think the battery is very low and since its not getting up to 14.4 volts it means more power is being used than being replaced.
Your only going to get up to 14.4 volts if its charging while no loads are being used by the battery.
On my system if the controller is showing 12 amps being produce and 13.6 volts, usually the battery is only getting about 4 amps while the 8 amps are being used by my fans, lights etc.
Your battery is good, it just needs a good charge to 14.4 volts.
After charging all day, your lifepo4 should sit at 13.1 volts with no load (minimum) after the sun goes down. If it reads less than 13 volts it means its no where near full maybe 50 percent or less.
I use a coulombmeter on my lifepo4 to get a more accurate SOC.

tk15 couloumb.jpg
 
And the Insta-Pot is a big load.........................

I actually don't use the instapot that much, maybe 15 minutes a day total. Bottom says it's 700 watts, so I'm using maybe 175-200 watts a day, during the day, which gets replaced before the sun goes down.

The charge amps are good, I think the battery is very low and since its not getting up to 14.4 volts it means more power is being used than being replaced.
Your only going to get up to 14.4 volts if its charging while no loads are being used by the battery.
On my system if the controller is showing 12 amps being produce and 13.6 volts, usually the battery is only getting about 4 amps while the 8 amps are being used by my fans, lights etc.
Your battery is good, it just needs a good charge to 14.4 volts.
After charging all day, your lifepo4 should sit at 13.1 volts with no load (minimum) after the sun goes down. If it reads less than 13 volts it means its no where near full maybe 50 percent or less.
I use a coulombmeter on my lifepo4 to get a more accurate SOC.

Don't really want to shut the fridge down. I am on my laptop quite a bit during the day. The meter I have for my charge controller always shows the battery charge going up during the day. It will appear full, but then drop down a bit, then fill back up, then drop down.
 
That’s common Mark… I know my situations I get to 14.4 but goes down quickly to 13.3 and then stays in the 13.2 to 13.3 for long stretches.
But I’d agree… you should have two 100ah batteries. Being the screenoholic you are. Haha! Keep that panel clean and such. I’d want two batteries for those cloudy days anyways…
 
That’s common Mark… I know my situations I get to 14.4 but goes down quickly to 13.3 and then stays in the 13.2 to 13.3 for long stretches.
But I’d agree… you should have two 100ah batteries. Being the screenoholic you are. Haha! Keep that panel clean and such. I’d want two batteries for those cloudy days anyways…
Considering getting a 2nd battery next month.
 
I actually don't use the instapot that much, maybe 15 minutes a day total. Bottom says it's 700 watts, so I'm using maybe 175-200 watts a day, during the day, which gets replaced before the sun goes down.

You are under-estimating your power use and over-estimating your solar power production, and the results are cumulative and additive.

You need to include inverter losses, and slowly depleting your battery capacity over time and use.

15 minutes a day at 700 watts draw will probably be about 220-250 watt-hours per day when inverter losses are included, and the 300 watt panels are probably producing at most 200 watts on average, maybe less. With simultaneous laptop and fridge loads, your system is not keeping up. And also, solar hours per day are decreasing, and the sun angle is dipping lower each day this time of year.

Your fluctuating voltage readings hint that the solar production is not keeping up with the power use.

You may need to add another solar panel or two, supplement power production with a small generator, or reduce your daily power consumption.

Try going thru a day without using the cooker, or a day with the laptop not being used at all (or very minimally) and monitor the voltage readings, lets see if they increase.
 

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