Brown outs

[Dave Hounddriver]

1 hour ago, Huggybearman said:

A fully charged 12v battery should be a little over 12.7 volts. At 50% state of charge it should be 12.1 volts. It is not advisable to discharge your battery below about 50% to prolong the life of your battery. 

Batteries have changed so much in recent years, due to the different demands from different applications.

My "12 V" battery, which is the same as AlwaysRts, peaks at 13.75 Volts in practice but the manual says it can and should go even higher every 2nd week of regular use by applying a 16 hour "equalization charge" of 14.46V.

It is considered fully charged at rest when it stays at 13 Volts.  It discharges to 12.2 Volts at 50% state of charge, which is considered the normal state of discharge under standard operating conditions but it will discharge to 30% charge without harming the battery provided you follow the correct procedure to recharge it.

The above is stuff I have been studying from the manual (yeah, who would have thought that modern batteries come with a 12 page manual that you really MUST read so you don't harm your investment).  The biggest mistake I was making, before AlwaysRt guided me in the correct direction, was to assume that all deep cycle batteries were the same.  They are not.

EDIT:  In the same way, all inverters and all chargers are not the same and since the battery and inverter and charge system are intimately linked it is important to match the 3-some so they all play nice together.

Edited October 20, 2017 by Dave Hounddriver

[Huggybearman]

10 hours ago, Dave Hounddriver said:

Batteries have changed so much in recent years, due to the different demands from different applications.

My "12 V" battery, which is the same as AlwaysRts, peaks at 13.75 Volts in practice but the manual says it can and should go even higher every 2nd week of regular use by applying a 16 hour "equalization charge" of 14.46V.

It is considered fully charged at rest when it stays at 13 Volts.  It discharges to 12.2 Volts at 50% state of charge, which is considered the normal state of discharge under standard operating conditions but it will discharge to 30% charge without harming the battery provided you follow the correct procedure to recharge it.

The above is stuff I have been studying from the manual (yeah, who would have thought that modern batteries come with a 12 page manual that you really MUST read so you don't harm your investment).  The biggest mistake I was making, before AlwaysRt guided me in the correct direction, was to assume that all deep cycle batteries were the same.  They are not.

 

Absolutely correct. Battery technology has progressed a lot over the last few years. Each manufacturer will have specific recommendations which need to be followed to ensure maximum life from your investment. The chart I provided was a generic one which will cover the 'average' type of wet cell battery one comes across. It would give a rough idea of the state of charge, or depth of discharge of that kind of battery.

Although your battery may well give around 2000 cycles, which is very good, I would still try and minimise the depth of discharge that you routinely go down to. Your battery will thank you for it. And so will your wallet.

Ken

 

[Dave Hounddriver]

7 hours ago, Huggybearman said:

I would still try and minimise the depth of discharge that you routinely go down to. Your battery will thank you for it. And so will your wallet.

Yes.  After your post I once again re-read that extensive manual and they provide a graph showing number of cycles of life vs depth of discharge and it proves your point.  Thank you.