Fast drain and corroded cable - related?

[dixonge]

Problems in the order that I can remember them:

1 - When I charge my laptop, the 1500w inverter gets warm and the fans kick in. This stops within 5 minutes after I unplug the laptop
2 - Last night we went from full charge to somewhere around 20% before we went to bed. Fridge is on gas. We had a new cellular modem hooked up and running and a couple of LED lights. That's about it. I'm sure we were using *more* electricity the first few nights we had the solar hooked up, but last night just drained everything. I heard the inverter's fault/error beeping so turned it off and switched over to the original house batteries.
3 - Double-checked water levels this morning, topped them off. Noticed some corrosion around the negative post on one battery, where the cable connects to the positive terminal of the other battery. The corrosion is just on the cable lug, not the terminal. (see pic) Both batteries have been connected and used less than 10 days.

   

I'm truly perplexed. I guess it *could* be the new cell modem, but I'm suspecting the one battery. It was low on water when we first got it, but I filled it before I connected it. It tested fine. But now I'm having second thoughts.

So I appreciate any thoughts you may have. Thanks in advance.

 

[Trebor English]

If the battery isn't full it will drain quickly.  You said you went from full to 20%.  If that full is based on a hydrometer reading of 1.285 or more then it probably is full.  Otherwise, it is not so clear what the state of charge actually was.

If the battery has been chronically undercharged it may have much less capacity than when new.  How do you charge it?

 

[highdesertranger]

link to picture is broken.

what's the total amperage of the devices you had on?
the inverter has a parasitic draw. how many amps is that? the cheaper the inverter the more the draw. the inverter should be turned off when not in use.
did you get the batteries back to 100% everyday?
or was this a cumulative failure?
what type of batteries?
Ah rating of the batteries?
what do you mean when you say switched over to the original house batteries?
do you have multiple systems?

highdesertranger

 

[dixonge]

If the battery isn't full it will drain quickly.  You said you went from full to 20%.  If that full is based on a hydrometer reading of 1.285 or more then it probably is full.  Otherwise, it is not so clear what the state of charge actually was.

If the battery has been chronically undercharged it may have much less capacity than when new.  How do you charge it?

Full based on charge controller. It was charging for a couple of days via solar panels with the inverter off. It's less than a month old and has been at full charge for most of the time.

link to picture is broken.

what's the total amperage of the devices you had on?
the inverter has a parasitic draw.  how many amps is that?  the cheaper the inverter the more the draw.  the inverter should be turned off when not in use.
did you get the batteries back to 100% everyday?
or was this a cumulative failure?
what type of batteries?
Ah rating of the batteries?
what do you mean when you say switched over to the original house batteries?
do you have multiple systems?

highdesertranger

I'm seeing the pic just fine, even on refresh:

https://vanlivingforum.com/attachment.php?aid=26449

Total amps I am unsure. After three nights on shore power where solar panels had good sun and batteries were fully charged, we then spent the night in a WalMart parking lot. Charged laptop, and it caused the inverter fans to spin up. Unplugged laptop, inverter fans went off. All other usage was minimal (LED lighting, recharging of walkie talkies, phones, etc.). I don't know the amps, but all those are minimal and have never caused any major drain. I suspect the inverter fans may really draw a lot, especially combined w/ the laptop adapter, which is 45w if not mistaken. But even that has been used several times without this issue arising. Maybe I've always charged during the day? Not sure.

I do turn off the inverter when not in use, but it stays on while boondocking. Otherwise we wouldn't even have lights, CO monitor, etc. at night.

Except for cloudy days the batteries get topped off each day. Two 6V 230ah batteries.

Yes, this is a separate system from house batteries.

 

[highdesertranger]

link still doesn't work for me. I get a "Thread does not exist" failure notice.

OK you are making statements that I believe you think are true but in reality you have no idea. I don't mean this in a bad way but,

"After three nights on shore power where solar panels had good sun and batteries were fully charged,"
how do you know this?

"All other usage was minimal"
how do you know? you already stated,

"Total amps I am unsure."
again how do you know you don't have a problem with one of these minimal use items, or the lap top charger or the inverter?

"Except for cloudy days the batteries get topped off each day."
again how are you coming to this conclusion?

obviously from what you are describing you should have minimal usage and fully charged batteries. but you don't , so we are missing something.

so on this second system it is not tied into the other system in any way?

why is your CO detector run of the inverter, it should be 12v?
also your refrigerator uses power even when running on propane unless it's a really old unit.
what about your water pump?
tank monitors?
propane detector?
water heater and furnace also use power.
radio?
radio memory?
clock?
etc.?

so we need to get an accurate(or semi accurate) reading of,
actual power usage?
actual SOC(state of charge) of the batteries

highdesertranger

 

[maki2]

Is the pug that goes into the laptop itself getting really hot right at the computer where it is plugged in? Or is it flakey and you have to jiggle it to get it to work? If so your power port plug inside the computer needs replacing and it could be what is causing your issues. Power ports are one of the first things that wear out on laptops. I recently had to replace the one on the laptop I am using to write this posting. Fortunately it was not located on the mother board. Go to youtube with your make and model # and type in power port to see if there is a DIY tutorial. I ordered the part and replaced it myself.

It could be the power supply is acting up. I ordered a 12V DC charger for my laptop to avoid needing to use an inverter when not on shore power. More versatile too as I can easily charge the laptop while driving.

Also your computer might need a good cleaning. Dirt inside the computer can cause overheating issues. If it is a laptop sometimes just blowing some canned air into the air intake vents can remove a lot of the dust that gets on the fan blades.

 

[dixonge]

This is a MacBook Air I bought from Apple about a year ago. I think the adapter just draws more power than the specs first indicated. The adapter gets very warm. It is a 'magsafe' connection to the laptop. There are no DC charging options that I have found.

 

[Weight]

The photo link doesn't work. Charge controller estimates of SOC indicated are never right.

 

[dixonge]

link still doesn't work for me.  I get a "Thread does not exist" failure notice.

OK you are making statements that I believe you think are true but in reality you have no idea.  I don't mean this in a bad way........

so we need to get an accurate(or semi accurate) reading of,
actual power usage?
actual SOC(state of charge) of the batteries

highdesertranger

It's really odd that you, as a moderator, can't see an image attachment... I put it on imgur for ya...

The cable connecting the two 6V golf cart batteries has some white powder which has formed on it near the connection to the positive terminal. At this point, this is the main question I have (why corrosion happens on new batteries) and the rest is secondary.

You are correct - I have not made a detailed, minute-by-minute log of the chain of events leading to the low power state.

As I stated previously, my only measurements are from the charge controller, which is limited. When the panels are fully lit, I see the voltage go up above normal 'SOC' - otherwise I see something approaching real SOC. I do not, on a regular basis, test individual cells with the hydrometer. When the controller indicates it is doing float charge, I presume the battery is pretty close to full. That's the best I can do until I get a 'proper' battery monitor.

My usage estimates are just that, estimates. But I am comparing the first few days, where the battery status indicators were all fine, to the days surrounding the low point. The loads I ran during that time that were different were mainly the laptop charging (with the resulting inverter fan usage) and the new cell modem/router/hotspot. All other devices (fridge, monitoring, water pump, etc.) were used the same across both timeframes.

Yes, the solar is separate from the factory house system. I connect using the shore power cable while disconnecting the house batteries.

 

[highdesertranger]

ok first off. you need some type of protection to prevent corrosion on the terminals. they make special stuff felts, paint, grease. or you can use regular paint or grease the idea is to block the oxygen from reaching the terminals.

a word on the terminals. those look like cheap auto part store cables, are those copper terminals or steel? if they are steel I would get rid of them.

voltage is a poor indicator of the state of charge. you need to use that hydrometer or get an amp counting meter. you can't go by voltage or what your charge controller is doing. you need to get a handle on your usage and getting the batteries back to 100% each and everyday.

"But I am comparing the first few days, where the battery status indicators were all fine"

to me this statement sounds like you are not reaching 100% everyday. again you can not go by the voltage or what the charge controller says. it sounds like you are undercharging your batteries and after a few days they are dead. I would check with the hydrometer everyday until you get this straighten out.

what make and model charge controller?
I might have missed the answer but are your 2 systems completely separate or are they tied together at any point?

highdesertranger

 

[maki2]

Is that the type of charger with a USB type C adapter as well as a 120V tip?  If so then you can install a high output 12v PD Type C USB socket   They make them in a round size that fit into the kinds of mounting brackets an aftermarket cigarette lighter socket fits into when people add one under their dash. That way you don't need to run a converter to charge you Mac, you just plug into the 12v USBC port. Be sure you use appropriate gauge of wiring for the amp draw from battery to socket. You can install a switch for the port so that it is not always powered to prevent parasitic drain as they usually seem to come with LED lights surround the port to indicate it is powered up. 

Sorry but I can't take the time to find you a direct link this morning. Just be sure the ouput is high enough to charge you Mac Air. Read carefully and research before you purchase it. This will really cut down on your power consumption and the heat issue as you won't need the converter to power it unless you are doing massive hours of video editing in which case you will probably need a converter.

 

[jonyjoe303]

I suspect you got voltage drop from the controller to the battery. I never trust the charge controllers to give me an accurate battery status. What I mean by voltage drop, the controller can be reading 14.4 volts but your battery terminals will only read 14.0 volts or even lower. Check the battery terminals with a multimeter while its being charged and make sure it reaches at least 14.4 volts, if it doesn't it isn't getting fully charge. 

One thing about charge controllers once it reaches 14.4 volts it switches to float, float is even lower voltage, so you might end up trickle charging your battery at 13 volts all day long, that will eventually reduce your battery capacity. If the battery gets fully charge quickly every day it probably already lost capacity. Luckily you got those heavy duty 6 volt batteries, they can handle abuse better then the cheaper 12 volt batteries. It might take you several days to a week to fully charge them to 14.4 volts with solar.

To fix the problem of voltage drop, you have to have a controller that you can adjust the bulk voltage. You might have to set the bulk voltage to 15 volts so that the terminals reach 14.4 volts.

The inverter fan coming on right away with a light load means the voltage is too low, to compensate the inverter has to use more amps to put out the same watts, this also lowers the battery voltage even more. This means you got a totally dead battery, voltage under 11 volts.

I also didn't see your original picture but the imgur works good.

Heres a picture of my solar system, I have a LED meter between the controller and battery. That way I can make sure my battery reaches max voltage.

 

[dixonge]

ok first off.  you need some type of protection to prevent corrosion on the terminals.  they make special stuff felts,  paint,  grease.  or you can use regular paint or grease the idea is to block the oxygen from reaching the terminals.

a word on the terminals.  those look like cheap auto part store cables,  are those copper terminals or steel?  if they are steel I would get rid of them.

voltage is a poor indicator of the state of charge.  you need to use that hydrometer or get an amp counting meter.  you can't go by voltage or what your charge controller is doing.  you need to get a handle on your usage and getting the batteries back to 100% each and everyday.

"But I am comparing the first few days, where the battery status indicators were all fine"

to me this statement sounds like you are not reaching 100% everyday. again you can not go by the voltage or what the charge controller says. it sounds like you are undercharging your batteries and after a few days they are dead.  I would check with the hydrometer everyday until you get this straighten out.

what make and model charge controller?
I might have missed the answer but are your 2 systems completely separate or are they tied together at any point?

highdesertranger

Now that you mention it, the cables that came with the inverter are copper, I guess I bought that one separate. Will replace.

I'm sure I reached max charge on some days, especially when the 400w of panels charged the batteries for two days straight, full sun, no load. Other days, I can only say 80% as a reasonable estimate, depending on the accuracy from the controller. 

The controller is this one:

https://www.windynation.com/Charge-Controllers/Windy-Nation-Inc/P30L-LCD-30A-PWM-Solar-Panel-Regulator-Charge-Controller-with-Digital-Display-and-User-Adjustable-Settings/-/628?p=YzE9MTc=

I do not yet have the battery temperature monitor connected.

Yes, the systems are separate. The only tie-in is plugging the shore power cable into the inverter. There was an entire thread on this setup, in which you participated...

 

[jonyjoe303]

with 400 watts of panels you should see at least 20 amps of charge power when the sun is overhead. What is the max your controller is putting out, it should show on the LCD screen. At 20 amps you should have fully charge batteries every day. If your not seeing 20 amps with a low battery something is definitely wrong. I don't think the cables are bad unless they are loose.

The manual wasn't to clear on how to adjust the voltage, but if you have voltage drop, you might have to adjust the overvoltage disconnect, increase that higher.

 

[dixonge]

The problem isn't in recharging. That part works just fine as far as I can tell, at least unless it is cloudy :/

I think the default charging levels were right in line for the manufacturer recommendations. I'll know more once I get better battery monitoring in place.

 

[dixonge]

Victron battery monitor now in place wired for monitoring midpoint. Also connected the temperature monitor to the charger controller. Haven't done any serious boondocking since then, maybe one or two days here and there. Levels appear to be fine, generally charging and discharging as expected. Last hydrometer tests were actually improved over previous, so maybe things are leveling out there. Even managed to charge while driving around in the smoky California skies!

Corrosion mostly stayed away after cleaning. The terminal end of the cable is tinned like all the rest, so it's not some inferior steel. Haven't treated it with anti-corrosion things yet.

Probably need to change a few settings on the battery monitor to make sure it's dialed in, but finding detailed instructions specific to my setup is harder than I think it should be. But I'll get there eventually