Inverter/Converter help?

[E_J_push_n_wind]

I'm looking to add a PSW inverter to my TT, I'm thinking somewhere in the neighborhood of 3KW. I don't necessarily need something perhaps that big however I'm thinking if I wanted to add battery capacity, this part I would not have to do again. Kind'a do it once and be done. I'm wondering if I could get help in directing me on how would be best to wire it? I'm wanting to isolate my converter when I have the inverter "on." I know it is recomended to have the inverter as close to the batteries as possible (for the current draw on 12V DC vs. 120 VAC) however I am thinking of running heavy wire and place the inverter in the enclosure with the connverter. I would like to somehow have a single switch as a cut-out (if that is possible) so as to "turn off the conver" as the inverter is switched on (a single throw switch that does both?). Is there a way to do what I'm looking for? Any help would be much appreciated.

The TT has two 6V deep cycle marine batteries right now. The idea is to have all outlets energized through the inverter realizing that my "power supply" is limitted by the number of amphours available with the batteries I have on board.

[mena661]

smkettner wrote:
Ahh perfect. 300 watts will serve you fine.

My small inverter I connected behind the breaker/fuse panel. For low wattage you can probably tap into the main 12v battery connection and call it good. Then use a small transfer switch to send power down the branch circuit that powers the convenience plugs. If you have two circuits with outlets you need two transfer switches.

I use 300w Go Power sine wave inverter for this service.
GP 12v 300w $171

Small transfer switch (almost plug and play)
15a switch $50

Way way easier than 3000w 😉

X2

[2oldman]

E&J push'n wipnd wrote:

By I/C I take it that would be and Inverter/Converter, all in one?

Yes. But that's irrelevant now.

[09FLSTC]

Now its making more sense. I'd consider the Samlex PST units I've used several of them and all are working great.

[time2roll]

Ahh perfect. 300 watts will serve you fine.

My small inverter I connected behind the breaker/fuse panel. For low wattage you can probably tap into the main 12v battery connection and call it good. Then use a small transfer switch to send power down the branch circuit that powers the convenience plugs. If you have two circuits with outlets you need two transfer switches.

I use 300w Go Power sine wave inverter for this service.
GP 12v 300w $171

Small transfer switch (almost plug and play)
15a switch $50

Way way easier than 3000w 😉

[E_J_push_n_wind]

smkettner wrote:
A 3000 watt 12 volt inverter needs to be wired for 300 amps. Pick an inverter and read the installation manual. With two batteries it would be best to be no more than 1000 watts. What exactly do you need to run? Get the actual input wattage rating. tv, dvd, satellite, laptop, cell phone etc will work fine on 150 watts to 300 watts.

I wired my 2000 watt inverter into just the microwave branch circuit with a transfer switch. Power goes down that one circuit only and never to the converter. I added one convenience outlet for any other item to be plugged in.

Or you can move the converter power connection to get power before your inverter but may require a subpanel or Go pOwer has a transfer switch that breaks out the power for the converter direct from cord or generator only.

If you have a compartment up near the batteries that is where the inverter goes. Then pull 120v wire back to the main panel to connect as needed.

Ya know, I'm no stranger to wanting to save a buck or two. I really do not need a 3KW inverter. I just thought it would be a good jumping off point. I'm really only look'n to operate the TV and DVD/entertainment center. I was thinking of "energizing" the whole TT so I could plug phone chargers in pretty much anywhere if I wanted. Nothing really more than that. I like the idea of placing the inverter near the batteries and running AC "the distance" vs. the other way around. Makes more sense I suppose.

So, even with a smaller inverter I'd still like to connect it the same way so that when I'm "on the inverter," the only AC outlets used will power small items. Not looking to drive a microwave or hair dryer or coffee pot or the like.

[E_J_push_n_wind]

BFL13 wrote:
"... The distance guestimated would be 15' to 20' or so. I did a cursory search for 100 amps at a 20' run and I got #6 AWG would handle 100 amps at 200'"

Try again. Yipes! 😞 One foot of #4 one way (1 ft pos and 1 ft neg) is more like it.

With four 6s you can run that 100a draw until the batts are about 50% down before they alarm off at 11v loaded. With two 6s, you can run that until they are about 75% SOC (25% down) before the 11v alarm goes off.

12v batts will do a little better before hitting 11v but the secret is AGMs. You can do down to 50% with two AGMs before hitting 11v alarm off. So if you have limited battery space or weight to two batts, and want to run a big invert load, get AGMs.

You know, I was at work when I did that search so when I say cursory. It's just that! I just took another look and looks like a lot of info is taken into account namely temperature. #6 wasn't even listed for a 100 amp run, anywhere.

[time2roll]

E&J push'n wind wrote:

smkettner wrote:
How may feet will you be from the battery? You will need minimum 4/0 wire about the size of a garden hose. Four batteries minimum, six+ preferred for 3000 watts.

Combo unit is fine or wire the inverter to provide power after the converter so that you have no issues.

My batteries are in the typical place on the tongue. The distance guestimated would be 15' to 20' or so. I did a cursory search for 100 amps at a 20' run and I got #6 AWG would handle 100 amps at 200'

Right now I've gotta stick with the two batteries I have as I am limited by how much weight I can pull. That's a topic for another thread though. I just have an idea to make it as simple as possible (the operation of it) so even a caveman could do it.

Can you expound on the latter part please? Wiring after the inverter after the converter?

A 3000 watt 12 volt inverter needs to be wired for 300 amps. Pick an inverter and read the installation manual. With two batteries it would be best to be no more than 1000 watts. What exactly do you need to run? Get the actual input wattage rating. tv, dvd, satellite, laptop, cell phone etc will work fine on 150 watts to 300 watts.

I wired my 2000 watt inverter into just the microwave branch circuit with a transfer switch. Power goes down that one circuit only and never to the converter. I added one convenience outlet for any other item to be plugged in.

Or you can move the converter power connection to get power before your inverter but may require a subpanel or Go pOwer has a transfer switch that breaks out the power for the converter direct from cord or generator only.

If you have a compartment up near the batteries that is where the inverter goes. Then pull 120v wire back to the main panel to connect as needed.

[BFL13]

"... The distance guestimated would be 15' to 20' or so. I did a cursory search for 100 amps at a 20' run and I got #6 AWG would handle 100 amps at 200'"

Try again. Yipes! 😞 One foot of #4 one way (1 ft pos and 1 ft neg) is more like it.

With four 6s you can run that 100a draw until the batts are about 50% down before they alarm off at 11v loaded. With two 6s, you can run that until they are about 75% SOC (25% down) before the 11v alarm goes off.

12v batts will do a little better before hitting 11v but the secret is AGMs. You can do down to 50% with two AGMs before hitting 11v alarm off. So if you have limited battery space or weight to two batts, and want to run a big invert load, get AGMs.

[wolfe10]

E&J push'n wind wrote:

smkettner wrote:
or wire the inverter to provide power after the converter so that you have no issues.

Can you expound on this please?

I suspect (please confirm) that he is suggesting that inverter output be routed to a sub panel with only those circuits that you want to have powered by the inverter. This ASSUMES that the inverter has a "pass-through" feature so that those circuits powered from the sub-panel are also powered directly from shore power or generator if either is present. This is actually the best way to wire an inverter and is the way many higher-end coaches are wired from the factory.

[E_J_push_n_wind]

smkettner wrote:
How may feet will you be from the battery? You will need minimum 4/0 wire about the size of a garden hose. Four batteries minimum, six+ preferred for 3000 watts.

Combo unit is fine or wire the inverter to provide power after the converter so that you have no issues.

My batteries are in the typical place on the tongue. The distance guestimated would be 15' to 20' or so. I did a cursory search for 100 amps at a 20' run and I got #6 AWG would handle 100 amps at 200'

Right now I've gotta stick with the two batteries I have as I am limited by how much weight I can pull. That's a topic for another thread though. I just have an idea to make it as simple as possible (the operation of it) so even a caveman could do it.

Can you expound on the latter part please? Wiring after the inverter after the converter?

[E_J_push_n_wind]

2oldman wrote:

E&J push'n wind wrote:
I would like to somehow have a single switch as a cut-out (if that is possible) so as to "turn off the conver" as the inverter is switched on (a single throw switch that does both?). Is there a way to do what I'm looking for?

If you buy an I/C it's all done automatically.

If you're sinking big bux into a unit, and preparing for heavy use, an IC has a much better charger than your converter. That way, you really are done.

By I/C I take it that would be and Inverter/Converter, all in one?

[MEXICOWANDERER]

Answering the question regarding a "switch"

A double-pole On-On switch allows switching both the leg and neutral to each device. You should look for a switch rated 25 amperes. An on-on switch toggle has two positions. Up or down. No middle position (which in other switches would be the "off" position.

[BFL13]

ewarnerusa wrote:
There was no load on it when it faulted. I do believe that others mentioned the bonded neutral something something that might trip up an inverter when I asked about on these forums. All other inverters I have used work this way, just that Samlex one didn't. And the Samlex one worked for directly powering things, just not through the shore power cable route. My solution was to get a different inverter since I decided I need PSW.

My MSW Vector 2000w and 1000w PSW Xantrex inverters both say not to run an AC dist with them but have no trouble running an RV "whole house"

Obviously it doesn't matter now, but IMO there must have been some "issue" other than that at the time. If there was no load then it must have been a connection issue that you didn't catch? Doesn't matter now anyway.

[ewarnerusa]

There was no load on it when it faulted. I do believe that others mentioned the bonded neutral something something that might trip up an inverter when I asked about on these forums. All other inverters I have used work this way, just that Samlex one didn't. And the Samlex one worked for directly powering things, just not through the shore power cable route. My solution was to get a different inverter since I decided I need PSW.

[BFL13]

They all say not to run an AC panel or words to that effect. You can still do the shore power cord trick though. They must be referring to something else, maybe that bonded stick house thing. Whatever.

There must have been some other "issue" overloading it at the time why it didn't work in the RV.