Small battery bank running an inverter

[GILow]

Look guys, it has become really clear that nobody will believe me that I have wired the inverter correctly, so today I dropped into the boat and took a photo, because they say, a picture is worth a thousand words. I've highlighted the inverter feed wire in the photo.

As you can see, this system setup is fine, I really don't understand why the manufacturers can't just make their batteries work properly.

[StuM]

I see your problem, the charger ammeter is installed upside down. That is a common cause of voltage drop.

[Jim Cate]

Originally Posted by StuM

I see your problem, the charger ammeter is installed upside down. That is a common cause of voltage drop.

Ohh, excellent, Stu!!!

Jim

[GILow]

Originally Posted by StuM

I see your problem, the charger ammeter is installed upside down. That is a common cause of voltage drop.

Damn! You have a sharp eye.

[conachair]

Originally Posted by StuM

I see your problem, the charger ammeter is installed upside down. That is a common cause of voltage drop.

He's in Aus, obviously a northern hemisphere charger

[kmacdonald]

Is there a rat living in that rats nest?

[zboss]

It's also worth noting that the labels on small devices are liars. Quite often the actual juice required is very different from what the made in China label says... so it's possible that any given device could be drawing a more or less than the rating. I had that experience with a 110v window fan I run through in inverter, although in my favor.

[rwidman]

Originally Posted by newhaul

Inverters not inverter generators Ron. The manufacturers tech told me once many years ago the keys to it are that the inverters are the same manufacturer same output and same length of independent power supply leads from the bank. Also you put each inverter independently into the house ac power system.

PS I do it all the time with elcheapo harbor freight 750 watt inverters.

If you are using separate inverters for individual circuits you should have made that clear in the original post. And if that's the case, they wouldn't have to be identical.

But why not just buy and install what you need in the first place? It would make wiring and switching much simpler, not to mention operation and troubleshooting.

[a64pilot]

Originally Posted by Uncle Bob

Well Matt, just what anchors do you have ??

Doesn't matter, they are too small and he doesn't have enough chain

[kmacdonald]

Originally Posted by Uncle Bob

Well Matt, just what anchors do you have ??

Doesn't matter if you anchor from the stern.

[newhaul]

Originally Posted by rwidman

If you are using separate inverters for individual circuits you should have made that clear in the original post. And if that's the case, they wouldn't have to be identical.

But why not just buy and install what you need in the first place? It would make wiring and switching much simpler, not to mention operation and troubleshooting.

Sorry my bad I didn't make that clear to you . Also as far as buying a bigger single inverter. Well 75% of the time a single 750 watt unit is plenty. So less idle loss . Secondly I paid 35 bucks for the first inverter and the second was free so I figured why not . Now I can run my lil 4 cup coffee pot that draws 825 watts( 110 volt) timed it and it runs for 7 minutes to brew my days coffee .( When I don't want french pressed.)
The main reason to not have a bigger single unit is I'm frugal.

[rwidman]

Originally Posted by newhaul

Sorry my bad I didn't make that clear to you . Also as far as buying a bigger single inverter. Well 75% of the time a single 750 watt unit is plenty. So less idle loss . Secondly I paid 35 bucks for the first inverter and the second was free so I figured why not . Now I can run my lil 4 cup coffee pot that draws 825 watts( 110 volt) timed it and it runs for 7 minutes to brew my days coffee .( When I don't want french pressed.)
The main reason to not have a bigger single unit is I'm frugal.

I was concerned that someone (else) might read your post and connect the outputs of two inverters together.

Mine has an automatic transfer switch and takes over the single 120 volt receptacle circuit on my boat. Nothing else, it couldn't handle the water heater or air conditioner.

[ramblinrod]

Originally Posted by a64pilot

If it's only one minute, you should be fine. I due to my advanced age think Mr Coffee or similar device when someone says electric coffee maker.
I too am a a Coffee addict, something that 20 yrs in the Army did to me.
Please understand though that your 12VDC deep cycle batteries are really in fact starting batteries, not deep cycle, but no real matter as you have them.
I still think your undercharging them, long thread so I don't remember if they are AGM or not, but if not a hydrometer is inexpensive and an easy test that will tell if they are being undercharged or not.

This "myth" needs to be "busted".

The most popular brand of marine batteries manufactured in USA are made by East Penn.

In the 12 V "Marine/RV" battery line up:

- Starting Batteries are starting batteries.

- Dual Purpose Batteries have heavier plates than starting batteries.

- Deep Cycle Batteries have heavier plates than starting batteries and more glass matt insulation than Dual Purpose.

So there are different designs for each type of battery service. It is not just a case of throwing whatever label one desires on the same battery design (at least in the case of Deka brand batteries).

That a different manufacturer or battery model has different design features for what they refer to as a "deep cycle" doesn't make it a "true deep cycle".

It would be like saying that a Chevy is a "bicycle" and the Rolls a "true car". They are both cars, one is just arguably a superior design of "car".

By the way, Rolls (previously Surrette) are about the best deep cycle marine battery design out there. This does not make all other deep cycle designs, "not true deep cycles", it just makes then inferior design for a lot less money.

So East Penn "deep cycle" batteries, are "deep cycle" batteries, Trojans are arguably a better (and more expensive) design of "deep cycle" batteries, and Rolls a better yet (and more expensive yet) design of "deep cycle" battery.

But please, do not call an East Penn manufactured "deep cycle" battery, a "starting battery", or a "dual purpose" battery; they aren't the same thing.

An East Penn battery is certainly compatible with inverter systems. As with any electrical system, it will perform properly if it has been designed, configured, installed, and maintained properly.

In the case of an inverter system, one has to consider the amount of current the battery bank is required to deliver in what time frame. That simple.

If one puts too high a load on a battery bank for short duration, it will cause voltage sag. If the voltage sage drops below the drop-out voltage of the components connected, they will drop-out. That simple.

If one puts too high a load on a battery bank for a long duration, the batteries will be rapidly drained. The more deeply batteries are drained each charge cycle, the shorter their life expectancy. That simple.

Putting a short duration C/2 load on any standard lead acid battery, will not hurt it. That simple.

"Starting Batteries" are designed to sag less, but as a result of those design compromises, have a lower tolerance for deep cycling. That simple.

"Deep Cycle" batteries are designed to tolerate deep cycling better, but will have more voltage sag under high loads. That simple.

"Dual Purpose" batteries are a compromise between both applications using one battery design. That simple.

Let's stop spreading battery myths and start proliferating battery facts.

[westwinds]

Originally Posted by GILow

It's a figure of speech Zee, a figure of speech. We are not doing anything to cats.

Certainly not, this refers to preparing a cat FISH for cooking

[westwinds]

About a Small Battery Bank Running an Inverter for coffee, get a single cup coffee brewer that uses less power, 700 watts: Keurig K130 in-room brewer.