Expected voltage sag?

ewarnerusa wrote:
I do appreciate your desire for more information before providing a response.

2oldman wrote:
Don't feel bad. Few OP's contain all information necessary. That's why it's beneficial to read all OP's posts before responding.

Sorry, but until you yourself provided a link to another discussion in which it was evident the OP's batteries are most likely pooched anyway he never said anything about this in any of his previous posts in this thread which I did read. Obviously you knew about this previous thread but I didn't ... we're not mind readers. :R

SoundGuy wrote:
Sorry, but until you yourself provided a link to another discussion in which it was evident the OP's batteries are most likely pooched anyway he never said anything about this in any of his previous posts in this thread which I did read.

I don't think so. The link I provided is on Page 1 of this thread. :S

SoundGuy wrote:
Sorry, but until you yourself provided a link to another discussion in which it was evident the OP's batteries are most likely pooched anyway he never said anything about this in any of his previous posts in this thread which I did read.

2oldman wrote:
I don't think so. The link I provided is on Page 1 of this thread. :S

Sorry, nope. Your post which includes the link to the other discussion in which the OP indicated his batteries may be toast is Post #19 in this thread and yes it is on Page 2 of this discussion. :S :S

SoundGuy wrote:
Sorry, nope. Your post which includes the link to the other discussion in which the OP indicated his batteries may be toast is Post #19 in this thread and yes it is on Page 2 of this discussion.

We must be talking about two different things.

The link in THIS thread which I provided (post 19), which YOU quoted, links to post #6 in this thread. You must be talking about something else. I have not linked to any other discussion thread. Someone else did that.

SoundGuy wrote:
.. he never said anything about this in any of his previous posts in this thread...

We know that's not true.

ewarnerusa wrote:
So capacity seems unaffected

Not sure why you believe this, your inverter 'load' test indicates something different.

Yep, you asked a simply question which which I have no info to share but your sag seems excessive to me.

:S

Quote from Page 1 Post #6

ewarnerusa wrote:
My batteries got hammered pretty bad last season while the trailer was in the shop. Solar was disconnected and batteries were deeply discharged. I suspected they were shot but I've tried nursing them back with equalizations and being maintained with temperature corrected 14.8V charging profile. But I think they're damaged. After a full day charge, the inverter draw alone with the laptop charger will drop the voltage to 11.6V and hold steady. The voltage will often recover back to 12.5+V even after running this load for a while. Voltage reading is coming from the SCC voltage sense wires at the battery terminals.

..

The OP's (new) 232 amp hour batteries could be in the ball park of 200 AH now. Maybe less. So pulling 90 AH over night could put him in the 60-70% range or about 12.3 V measured with no load.

The sag is too much but the voltage seems reasonable in the morning.

I'm wondering why his laptop is pulling 90-100 watts all night. Is his laptop crunching numbers all night? It seems when his laptop battery gets full his usage should go down.

Laptop is a Dell XPS and the charger is rated at 90 watts. Kill A Watt confirms that. It read 90 watts in the evening and in the morning, so I assumed that's what it did all night, too. It is over 6 years old on the original battery.

#1 reason for voltage drop (besides load) is wires are too thin.

You need to measure the voltage on the batteries under load AT the batteries, then measure at the inverter. The difference is your voltage drop. Anything more than 0.10v is too much.

This is a great calculator.

http://www.calculator.net/voltage-drop-calculator.html

13.5 is a typical fully charged battery, 10.5 is the kiss of death for a battery.