Battery State

[Trotter]

I can understand the theory of not allowing the leisure battery below 12volt. But when the battery level is at say 12.6 , Charging a laptop drops the indicated level to 11..9 Pulling the plug, the level reverts immediately back to 12.6. Is this normal, or am I damaging my batteries.
I have 270 ah.

 

[saxonborg]

Hope it’s not something terminal.

 

[jagmanx]

As per post #3..
But why not
1 Only use LB's to charge laptop when running or good sun.
Or battery stays at 13.5+ even when charging in the day.
Use your laptop on its own battery in the evening until maybe it shows 40%..switch off
Recharge the next day..
This works for us even now when daylight is getting down to 50% and below.

If I really need Tinternet I can always use my phone which can be kept fully charged with a uSB powerbank
Said powerbank to be recharged next day.

Are you charging off a 12V DC to 19V DC which is best
An inverter and 230V charger is wasteful...However with 3 LBs you have loads of power.
PS our LB has never been below 12.5V even at 3am !

 

[Trotter]

Charging 19v on laptop tbh like the laptop for it’s screen size watching tv via iPlayer. If no internet I watch movies saved to a brick. When on the move I try to charge everything. Today I’m taking a day off driving. Batteries have recharged to 12.6 using solar only. Lovely place but dappled sunshine became of trees. If I’m concerned about discharging batteries today, I’ll not use the leccy kettle
While abroad my phone is my only access to the internet. I use that to operate iPad and laptop as well as the phone of course, My reason for asking was because of the way the voltage dropped when discharging.
Even after 18 of ownership, I’m still a newbie with so much still to learn
Thanks to all for replying

 

[Trotter]

18 months of ownership

 

[wildebus]

I can understand the theory of not allowing the leisure battery below 12volt. But when the battery level is at say 12.6 , Charging a laptop drops the indicated level to 11..9 Pulling the plug, the level reverts immediately back to 12.6. Is this normal, or am I damaging my batteries.
I have 270 ah.

The voltage dropping below 12V is fine under load and nothing to be concerned about. Usually.

A laptop is rarely a high power draw so to drop from 12.6V to 11.9V just on that doesn't sound that right TBH. I presume this is via a 240V inverter and the drop is when the laptop PSU and Inverter are switched on? How big is the inverter? A big inverter can be very inefficient with a small load but even then that is still a pretty big drop. (I'd expect that kind of drop on a >1000W load)

Without wanting to worry you (probably too late!), have you fuses between each battery (presuming you have more than 1) and the common +12V? If so, check each fuse is intact (you'll have to disconnect one side of the fuse to check) to make sure you are not running on less than all batteries.
It does sound like you may be running on less battery power than 270Ah. Does your battery pack either seem to run down quicker than you expect - or alternatively charge up faster then you expect?

 

[Trotter]

Dave. I’m Running 2 x 135 batteries in parallel taking the + from battery one and - from battery two . Batteries are fused @150amp once on the + side out.There is no fuses between the batteries only using 25sqm cables pos to pos , neg to neg.
I’ve got 100amp of solar along with a Ctek D250 (you know this, it was you who I asked advice from) . Batteries were full yesterday, after a longish drive. Last night took a bit of a bashing. Kettle laptop and such. Today I’ve not moved, started from a low level 12.2 Now showing 12.4 Only on solar with dappled sunshine. Again leccy kettle has been used. I’ve since put it away.
A total increase of 0.2v over a day doesn’t bother me over much. As I’ve said, dappled sunshine, kettle used, iPad and phone charged. All this with only 100ah of solar trying to charge 270ah of battery. I wouldn’t had thought I had a problem.
My worry was the indicator dropping so low when under a heavy load.

 

[wildebus]

I think your battery was not really at the 12.6V due to the way voltages are read when under charge/discharge.
So nothing to worry about, but your battery was really a bit lower than you thought.

 

[Trotter]

There’s always been something of black magic to electrickery. I’m getting to the stage of, if it doesn’t go bang, or catch fire, I’m probably okay.
I do tend to depend on the ctek to charge the batteries, so staying put, and using the inverter is a new one for me. Trying to figure how much I can take out of my power, and not discharge too far. As I understand, 12.02v is far enough.
As I said previously, the sun was dappled by trees. So solar couldn’t be depended on. Having said that, solar was my only input today. Probably tomorrow also.
My future plans include a 850w cook hob/ring thing. Cooking is fun, I’m told. Haven’t killed myself yet, Tis still early.

 

[trevskoda]

Think you mean 100w of solar which is about 7/8 amps on full sun midday.
When the batterys are charging you should see 14.4 and after a few hrs rest about 12.7 v.

 

[Trotter]

I only see 14.4 from the alternator. And 12.6 at rest, when fully charged.
I don’t honestly think there’s a lot wrong with what I’ve got. When parked, I’ve got a small panel try to charge a big(ish) battery bank. This isn’t being helped by my tea addiction. Free leccy is more attractive to me than paid for lpg.
I’ll not use the kettle today, the leccy bike battery, what I bought the inverter for, still has plenty of charge . So it’s going to be an lpg day.

 

[trevskoda]

There is summit wrong if not seeing 14.4 from solar,what regulator are you using and size of supply wires or a fuse blown,get the meter out and go round the sys.

 

[Trotter]

There is summit wrong if not seeing 14.4 from solar,what regulator are you using and size of supply wires or a fuse blown,get the meter out and go round the sys.

Don’t think so. 100w panel serving 270ah battery. Getting 12.9 v from 16v pv on the Epver MPpT controller at the moment with an overcast sun.
Having said that,I’ve probably got it all wrong. I’ll look into getting a state of charge meter instead of relying on the Chinese temp voltage readout I’ve got atm.
Seen one on YouTube. Trouble is, when do you stop spending and start enjoying?
I’m aware that my solar panel is probably undersized for the batteries.

 

[trevskoda]

Any clear sky im hitting 14.4v ,today rain and over cast 13.7 and above.
Some control units are ajustable for peak output,have a we nosey.

 

[nabsim]

you can get a Bluetooth dongle for some of the epver controllers Del, the one I had was £25 off eBay I think.

i wouldn’t trust the kit you use to tell voltage and amps it has always given funny reading, don’t know if it’s the kit or where you plug it in. Use your multimeter if you want to be sure, you already have one so no need to spend

 

[Trotter]

I like the idea of the dongle. But I’ll wait until I see you before I do anything.
What do you mean about not trusting the kit I’ve already got? I’ve now got three bits of kit,all reading different figures, one of them should be, maybe right.
The multimeter idea sounds a good one. Now I’ve repositioned the batteries,it wouldn’t be difficult to run a live/ neutral line to the bulkhead and take a reading from that. Although one of the probes is kaput. I keep looking at getting one of Lidl or Aldi’s finest..
Settled down to a dinner of salad and bratwurst. Question is, do I struggle with the third one, or have it in a sandwich tomorrow.? Decisions, decisions.

It’s gone

 

[trevskoda]

ebay £2.50 for multimeter.