Inverter Pros/Cons

[PNW_Steve]

Originally Posted by o1marc

Haven'y gotten that far yet. Will have enough battery to run that converter if that's whats need to supply my fixtures.

Here is a good read on inverter/battery sizing: https://www.solarpaneltalk.com/forum...-size-tutorial

Lots of good info regarding solar, batteries and low voltage systems on that site.

[brokedown]

The one you ordered is 3000w peak and only 1500 continuous. It's cheaper than I would have expected for a 1500w pure sine wave though.

[o1marc]

Originally Posted by PNW_Steve

Here is a good read on inverter/battery sizing: https://www.solarpaneltalk.com/forum...-size-tutorial

Lots of good info regarding solar, batteries and low voltage systems on that site.

Originally Posted by brokedown

The one you ordered is 3000w peak and only 1500 continuous. It's cheaper than I would have expected for a 1500w pure sine wave though.

I meant I got the offer from Amazon, didn't get the unit from them yet. So looks like a good deal to you?

[PNW_Steve]

Originally Posted by o1marc

I meant I got the offer from Amazon, didn't get the unit from them yet. So looks like a good deal to you?

I can't really speak to the value. The reviews aren't stellar.

I don't have much experience with the brands of inverter discussed above.

FWIW: I have purchased a number of Xantrex and Trace inverers and had extremely good luck with them.

Please let us know how it works out for you?

[o1marc]

Originally Posted by PNW_Steve

Here is a good read on inverter/battery sizing: https://www.solarpaneltalk.com/forum...-size-tutorial

Lots of good info regarding solar, batteries and low voltage systems on that site.

According to that I would need 36v to power the 3K, correct?

[PNW_Steve]

Originally Posted by o1marc

According to that I would need 36v to power the 3K, correct?

You can run a 3000watt inverter load from a large enough 12 volt bank. That article give great advice on why you shouldn't.

The internal resistance in your batteries limits the maximum current that you can draw from the bank.

There is another article out there that explains it well. I am trying to find it for you rather than trying to recreate it....

I'll be back ☺

[david.dgeorge07]

Originally Posted by PNW_Steve

You can run a 3000watt inverter load from a large enough 12 volt bank. That article give great advice on why you shouldn't.



The internal resistance in your batteries limits the maximum current that you can draw from the bank.



There is another article out there that explains it well. I am trying to find it for you rather than trying to recreate it....



I'll be back ☺

Maybe I’m missing something, but terminating a 2/0 copper cable is not that hard. Either crimp or solder or both. As long as it is done properly it isn’t a big deal. I have done it a bunch of times without issue or incident. Am I missing something?

[Chess]

Originally Posted by Thomas810

I would love more detail on what you did... cut out switch and all with the batteries... that sounds like exactly what I might want to do to save from always running the engine when I do stuff in the Bus... I actually purchased an 800 watt AC unit for the bus and wanted to start using it but was scared to run down the bus batteries if I used it... is there some reference that you know about to wire like you described? I have two batteries in the bus - but they are for cold cranking the engine... not deep batteries... its not clear to me how you connected in the third battery... It sounds like you used something like this... https://www.powerstream.com/battery-isolator.htm

I've read through this thread twice and think I'm beginning to understand. Please correct me where I'm wrong. So this battery isolator can be used to power a second (and third) battery from the original battery. Those additional batteries can be deep cycle batteries used in leu of shore power. What would be needed between the deep cycle batteries and the electrical panel?

[JDOnTheGo]

Originally Posted by o1marc

According to that I would need 36v to power the 3K, correct?

Yes, that would be "ideal" if using lead-acid batteries.

There are a couple of things to watch out for in less than name brand inverters. The biggest, in my opinion, is noise. Some of them have big fans that run full blast all the time. From there the differences can be difficult to measure. The discussions I've seen over the years tend to indicate short life span, less than ideal efficiency, and output that is not nearly as "pure" as it should be.

[PNW_Steve]

Originally Posted by david.dgeorge07

Maybe I’m missing something, but terminating a 2/0 copper cable is not that hard. Either crimp or solder or both. As long as it is done properly it isn’t a big deal. I have done it a bunch of times without issue or incident. Am I missing something?

We are not talking about the cables.

Batteries have internal resistance. When you draw current from the battery you will see voltage drop across this resistance. The greater the current draw the greater the voltage drop.

It effectively limits the maximum current that you can draw from a particular battery.

[david.dgeorge07]

Originally Posted by PNW_Steve

We are not talking about the cables.



Batteries have internal resistance. When you draw current from the battery you will see voltage drop across this resistance. The greater the current draw the greater the voltage drop.



It effectively limits the maximum current that you can draw from a particular battery.

I guess I was picking up on the wrong thing in the article. It says you need a $1000 tool to terminate larger cables.

As long as you are not exceeding the battery’s current spec by spreading the load across a large enough bank you should be ok, right? If you want to draw 150 A you should be ok with 6 batteries that are rated for 50 A - putting you at 50% of rated output.

Am I still missing something? It matters to me because I’m working on upgrading my battery bank.

[Iceni John]

Originally Posted by david.dgeorge07

I guess I was picking up on the wrong thing in the article. It says you need a $1000 tool to terminate larger cables.

Nah! I use a FTZ 94284 cable crimper, one of the few that makes proper circumferential crimps instead of just hammering a dent into the lug, and it was less than $200 from K.L.Jack. It works on everything up to 250 MCM (that's bigger than 4/0!), and makes perfect gas-tight crimps every time. For smaller cables I use a Harbor Fright hydraulic crimper that works surprisingly well for such a cheap tool, but its dies are labeled with nonsensical sizes.

John

[JDOnTheGo]

Affordable cable crimpers come in a variety of forms. I these hydraulic "press" style found on Amazon for $40 or so. Even less expensive is available.

For battery discharge rate, "C-rate" is the term to research. The referenced article is very good and discusses this. It states "as a general rule the maximum charge/discharge current for FLA batteries is C/8, and SLA/AGM is C/4."