Which 48v inverter to use?

Tshillingburg

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I'm through my 7th 80 cell pack out of 14 and looking towards getting an inverter. I have the same charge controller as Peter and Mike (PCM60X), not that it matters. I'm in the US and my plan is to power my house or at least most of it one day. My packs are 176.5 Ah and built closely to Mikes or Peters. Will the 4000w inverter be enough to power a house?

I'm trying to cover everything to give a good representation of what it will look like built to my house. It will be modeled after Peters and with guidance from my father in law who is an industrial electrician. I'll be running lights, dishwasher, air conditioner at times, some fans and the other small electronics including tvs, Xbox, etc. I will also have a stove, microwave, toaster, etc.

I'll also be tied to the grid.

I'm not completely clueless so I know that I can't have all of this on the same load and that thiswont work to power my whole house.

I guess my question is, given the information, what's the best inverter to start with and use for my 48v system that will be? I suppose I could also run them in parallel worst case scenario.

Thanks for any answers.
 
What inverter are you looking at? I know you say 4000W, but which one? The PCM60X is just a charger, that I can tell (I don't have one myself and have limited knowledge of its functionality).

If you two inverters, you can get 240V @ 4000W, or you can get 120V @ 8000W, depending on how it's wired. Note: Use caution if they are not specifically designed to handle these configurations. Either configuration can cause some serious damage/injury if not done right.

Some inverters are smart enough to just turn them on and they are ready to go. Others, there is a sequence you need to follow in configuration and powering on the unit. (ie. some units you have to turn on the 1st inverter, then power the second one after the 1st one is fully energized)
 
EKorishan said:
What inverter are you looking at? I know you say 4000W, but which one? The PCM60X is just a charger, that I can tell (I don't have one myself and have limited knowledge of its functionality).

If you two inverters, you can get 240V @ 4000W, or you can get 120V @ 8000W, depending on how it's wired. Note: Use caution if they are not specifically designed to handle these configurations. Either configuration can cause some serious damage/injury if not done right.

Some inverters are smart enough to just turn them on and they are ready to go. Others, there is a sequence you need to follow in configuration and powering on the unit. (ie. some units you have to turn on the 1st inverter, then power the second one after the 1st one is fully energized)
I was looking at something comparable to the PIP4048MS but that will work in the US. As long as 4000w will work and I can parallel the together then that's the plan. I guess it doesn't matter whether i parallel two or just but a 10000w inverter. I just noticed the price of 10000 watt and it's up there. I was going to start with a 4000w and take baby steps to make it bigger as my wife lets me spend more money haha

What do you use?
 
I don't have one in service as of yet. Altho, I do have a Smart-UPS that I will be using as a tie in. The great thing about those is that it will read the incoming AC and phase itself to match the feed-in power. Now, this doesn't mean that it outputs to the same wiring. It'd be a total down-stream setup. Smart-UPS' you can serial or parallel them as I mentioned above, but there's a trick to it as I also mentioned.
Unless, you get ones that are specifically designed to be master/slave; then it takes all the headache out of the equation, well, most of it.

The reason I have the Smart-UPS is because it's a 3000Watt unit that I paid $75 for. No batteries came with it, so shipping was relatively cheap. I'm upgrading some of the wiring on it so it can handle a continuous load on it better (they are normally rated at only about an hour of continuous use, i plan on many hours)
 
In the U.S., if you want grid tied and battery back up in one inverter, the OUTBACK GFX series will do this. The downside is that you HAVE to have batteries installed to use the inverter....so if you ever disconnect the batteries you wont be utilizing your solar panels.

There are other ways to do it with two inverters and transfer switches, but it gets expensive.

MPP solar makes the ideal hybrid inverter with grid only, off-grid, and hybrid modes, but it is not UL listed for grid tie in USA. Output is 240 volts, so a transformer is required for use in the USA.
 
My own plan is to use multiple smaller inverters, each with its own dedicated load(s). My place is small enough that switching them on and off as needed wouldn't be much of a problem and it would save energy. As you have noted big inverters are expensive.
 
APD said:
In the U.S., if you want grid tied and battery back up in one inverter, the OUTBACK GFX series will do this. The downside is that you HAVE to have batteries installed to use the inverter....so if you ever disconnect the batteries you wont be utilizing your solar panels.

There are other ways to do it with two inverters and transfer switches, but it gets expensive.

MPP solar makes the ideal hybrid inverter with grid only, off-grid, and hybrid modes, but it is not UL listed for grid tie in USA. Output is 240 volts, so a transformer is required for use in the USA.

Thanks for the information, it was very helpful. I like the idea of the gfx but it's not ideal for me to have a thansformer and Togo through all of that (Too bad it's not 110). I guess my best route is to go back to the single 4000w inverter when I can find a good US version of the pip4048. If it exists....more research to be done today. I'll update with any findings. Thanks for the great information from all


Elmo said:
My own plan is to use multiple smaller inverters, each with its own dedicated load(s). My place is small enough that switching them on and off as needed wouldn't be much of a problem and it would save energy. As you have noted big inverters are expensive.

It seems like this is the best option. I'm ok with doing that or putting them in parallel.
 
Korishan said:
I don't have one in service as of yet. Altho, I do have a Smart-UPS that I will be using as a tie in. The great thing about those is that it will read the incoming AC and phase itself to match the feed-in power. Now, this doesn't mean that it outputs to the same wiring. It'd be a total down-stream setup. Smart-UPS' you can serial or parallel them as I mentioned above, but there's a trick to it as I also mentioned.
Unless, you get ones that are specifically designed to be master/slave; then it takes all the headache out of the equation, well, most of it.

The reason I have the Smart-UPS is because it's a 3000Watt unit that I paid $75 for. No batteries came with it, so shipping was relatively cheap. I'm upgrading some of the wiring on it so it can handle a continuous load on it better (they are normally rated at only about an hour of continuous use, i plan on many hours)

Can your UPS work with lithium voltage? Also, what about the people I've seen say they can't run 24/7? How did you disable the charging mechanism? I have a very large UPS that weighs like 75 pounds without batteries. I know it's 48v and believe it is 3000w as well (I'll have to check). I got it for $30 at the state surplus store lol.

Back on topic, this is the inverter I am looking at. It's 4kw and is parallelable. It is very difficult to find inverters for US voltage that have high wattage outputs and do not cost $3000.
https://voltaconsolar.com/conversol-5kva-48vdc.html
 
Tshillingburg said:
Thanks for the information, it was very helpful. I like the idea of the gfx but it's not ideal for me to have a thansformer and Togo through all of that (Too bad it's not 110). I guess my best route is to go back to the single 4000w inverter when I can find a good US version of the pip4048. If it exists....more research to be done today. I'll update with any findings. Thanks for the great information from all

The GFX does NOT require a transformer (unless you want to run a 240 volt load). The GFX is for the USA market.

The MPP solar is the one that would need a transformer.
MPP also makes a 120volt off grid only inverter, with no grid tie capability.

An important decision you have to make first is whether or not you will be using your existing wiring in the house or if you are going to run extension cords from the inverter, or create a whole new sub panel for off grid. This will determine what type of inverter is best for the situation. If you want to do a legal grid tie, you will need a UL listed inverter.
 
mike said:
Can your UPS work with lithium voltage? Also, what about the people I've seen say they can't run 24/7? How did you disable the charging mechanism? I have a very large UPS that weighs like 75 pounds without batteries. I know it's 48v and believe it is 3000w as well (I'll have to check). I got it for $30 at the state surplus store lol.

The UPS normall charges at 24V. What I mean by that is that the batteries are connected in series. I figured I could possibly connecteither two connections of 12v, or one connection of 24v. I'm probably going to try for the 1 connection of 24v. So I might have two units so I can build a larger pack setup at 48v and then split to two 24v lines to the UPS's. I haven't quite thought that far ahead yet. What I like is that the UPS can be powered one w/o a battery connected, or can be powered w/o AC power.
 
There is tons of different UPSs out there. I have all from 12V to 96V at home and i also had >300V at work (Battery voltage)
Problem with most of them is that they have fixed voltages and there fore you cannot set custom voltage levels.

For Lead acid this would work great as long as you stick to same type of batteries as from the start or equivalent types. LA also have different voltages for Float vs Bulk and i have seen people change batteries in some without looking and 6 month later they were destroyed... Yes due to voltages is our guess since it was way way off.
Its just a side note for those out there that may read "UPS - that i do" - without understanding some of the parts :)

Of course also some UPS systems are not made to be running 24/7 but that i leave since it was covered earlier.
 
The Lithium packs wouldnt be connected directly, of course. I'd have an intermediate controller (DC-DC, PWM, or something similar). And the Smart-UPS do have the ability of being able to be adjusted via software. Though, you can't just open up a nice friendly app like Pete uses and just click a few buttons and blammo, changed :p Have to connect using a terminal app and adjust the setting through a Command line type setting.
I'll make a short video when I get some of the traces beefed up. I'll also have some heatsinks added, and add a few more mosfets/caps to help with loads. I've already done a lot of research on working the UPS' and converting them for offgrid use ;)
 
Yeah they do have decent stuff inside. I have been using UPS online 24/7 before :) Yeah videos and alot of pictures we like! :=)
 
No, keep it out. you can use it for experiments, load tests, charging variations, etc. Not to mention, you could sell it one of us real cheap ;)
 
Korishan said:
No, keep it out. you can use it for experiments, load tests, charging variations, etc. Not to mention, you could sell it one of us real cheap ;)

I can't remember if you live in the US or not? But if you do and want to make a trip to PA, I'll tell you where the store is to go get some. Lol. They always have all kinds of junk. Every time I've gone in for the past few months, there has been a full pallet of UPS there. Most of the time they're the black 24v 980w models. I've also gotten some brand new unopened 400w before. Then they also have the massive "it takes 2 people to lift" versions. I should start grabbing those ones up as I see them. They're all $30 each regardless of size or capacity.
 
Wow! I live in Fl. But at those prices, worth paying someone/company to ship them here. Id like one or two of those larger units, of course ;)
 
No problem. I don't want them with batteries anyways ;)
 
Someone gave me a 1500W APC 24V UPS, I"m leery of basing too much of my planning around it because I don't think it's made for the long haul as an inverter. It worked fine before the LA died and now it's sitting in storage. I think I'm going to dig it out, wire it up to use 7s lithium ion and keep it as a backup, it's big enough to run any single load I have.
 
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