To Invert or Not to Invert - That is the question!

[HJLowell]

Originally Posted by Tizbad

I met a guy with a King Aire and he can run his front A/C on the batteries. I think it had (16) 6-volt batteries. Don't know if this is standard equipment or not?

Yes
For a million + $$$ coach it can be [emoji106][emoji106][emoji106]

[Squerly]

Originally Posted by Tizbad

I met a guy with a King Aire and he can run his front A/C on the batteries.

Yep, I can too. Just not for very long.

[Stuart W]

Originally Posted by Squerly

leaving it on also means that, should shore power go down, the inverter will continue to feed power to whatever is on. There could be dead batteries when you return.

A totally agree with this.

[twinboat]

Originally Posted by Stuart W

A totally agree with this.

That goes along with the bilge pump on or off argument, in a boat.

Some don't want to kill the battery running the bilge pump, but what good is a charged battery on a sunk boat ?

If my inverter runs the fridge, I'll leave it on hoping I get back to it before the batteries are dead. That gives me more time before my food spoils.

[BrokeDown]

Originally Posted by twinboat

I'll leave it on hoping I get back to it before the batteries are dead.

Most of our coaches have an Energy Management System that will run the generator to charge up the batteries when they get to a set level. That being the case, we should be able to run for a pretty long time without shore power.


Most AGMs should not be ran lower then 50% charge which in my case is 12.3 volts. I set my EMS to start the generator at 12.4 volts.


-B

[HJLowell]

Originally Posted by twinboat

That goes along with the bilge pump on or off argument, in a boat.

Some don't want to kill the battery running the bilge pump, but what good is a charged battery on a sunk boat ?

If my inverter runs the fridge, I'll leave it on hoping I get back to it before the batteries are dead. That gives me more time before my food spoils.

Thats smart

Concerning loosing shore power

Both of my current Inverter chargers shut down when the Batteries get down to 10.5
Volts.

As far as bilge pumps, my current boat has 5
Compartmentalized.
The House batteries, aft mounted power the rear 3.
Non are powered by the 8, 6 volt deep cycle Inverter batteries. Located foreward.

The 15 KW westerbeke generator can bet set to start also.

The marina we are at seldom looses power for more than a few hrs. So in 19 year s
I have never set the auto start mode on the generator.

[twinboat]

Originally Posted by BrokeDown

Most AGMs should not be ran lower then 50% charge which in my case is 12.3 volts. I set my EMS to start the generator at 12.4 volts.


-B

AGM and flooded batteries can safely be run down to 15% capacity.

It will cut their life in 1/2, if done routinely, but an occasional deep discharge will not damage them.

This DOD, ( depth of discharge ) chart is from Lifeline Battery. I marked 50% and 15 % DOD cycle life.

[BrokeDown]

Thanks Twinboat1. With the expense of these things, I would prefer that they last as long as possible! LOL

[twinboat]

Originally Posted by BrokeDown

Thanks Twinboat1. With the expense of these things, I would prefer that they last as long as possible! LOL

I get that. In my situation I don't have the space for 4 batteries so I run the 2, that I can fit, down deeper.
They will have a shorter life but will cost 1/2 as much to replace.

[CampDaven]

My inverter died about a year ago. And I don’t need it.
I don’t boondock. So, the inverter is bypassed and I have a smart charger on the 6 volt batteries.

[Spikester]

We have 4 Lifeline 220AH batteries that were installed 5/14, have over 6550 cycles on them, still operating at over 100% capacity that last time I checked them.

[BrokeDown]

Originally Posted by Spikester

still operating at over 100% capacity that last time I checked them.

Spikester, how are you checking them?

-B

[twinboat]

Here is a chart, from the Lifeline battery maintance manual, of expected life cycles, based on depth of discharge, of their batteries.

6500 cycles is a discharge of maybe 5% deep.
That's about 22 AH each cycle. You could use a cheap marine battery for that kind of use.

[Spikester]

Quick answer, when bank is fully charged, I open circuit the battery (no loads), apply a constant 22 amp load (20 Hour Rate), and time how long it takes for the battery bank to get 10.5VDC. Immediately reconnect the battery bank and charge it back to 100%. Not something I do all the time or recommend doing all the time. I did it this summer because of the number of cycles on the battery bank. Only real way to measure its performance.