Hi
 

I'm new to this forum and new to all of this but understand a little. Living in a 2 bedroom apartment, solar is not an option (body corporate won't be happy for one and I dunno where I'd even be able to mount panels). Looking to implement some sort of system to be able to work through load shedding. Don't care about stoves or kettles or fridges, just a PC (which probably draws a bit as it mines crypto all the time. 800W PSU but I reckon it draws around 400W-500W most the time (nicehash says the GPU is drawing ~230W)), laptop, some screens, router and a 3d printer which I need to run. Maybe a TV on rare occations, the rest I can live without until after load shedding.  Noise (it's gonna have to be in my living area, can't put it outside or in a garage) and space are a factor and I think the current electrical installation isn't great.

I'm thinking either a 3kW or 5kW system (mostly guestimating). Solar not a future consideration. Would prefer to not break the bank, closer to 10-15k would be nice but if that's too low, I guess I can change my budget. Plugs I need on aren't all in the same place and I don't want some trolley just out in the open, want something installed by the db.

I'd just like to understand where to look and what to consider. Can probably install myself, but if that's not a good idea I guess I'd get someone in.

Any ideas for a starting point (even if it's another thread, just looking for up to date info)

Maybe consider a mobile UPS trolley, some can take Solar for future expansion. The below should give you some idea. There are others on the market as well.

https://www.inverter-warehouse.co.za/collections/specials/products/zuva-back-up-box-2

I was looking at something else, a colleague from work recommended this 
https://www.geewiz.co.za/load-shedding-solutions/108831-axpert-type-pure-sine-3000va-inverter-trolley-2x-100ah-battery-8-hour-battery-life-kit-3000w-60a-mppt-solar.html which looks like it's specs are higher, unless I'm missing something, which I thought to perhaps mount the components and wire it into the DB appropriately.

Also I see the enclosed batteries people are talking about on here (at a much higher price)- is there a major advantage for a simple setup like I'm looking into (never going to have solar).

Just no clue on how loud it is, or whether there's something better suited. I dunno if 1kW is gonna cut it, unless I'm overestimating how much I need (2 screens, TV, Router, a dell laptop (180W PSU) , 3080 gaming rig (800W PSU, I guess it uses around 1/2 of that most the time), and a 3d Printer (500W or so) or 2), which was leading me to think 3/5kW.
 

If my budget is too low, can raise it, was just wondering what's necessary. 

Edited October 28, 20214 yr by Pasito

For your budget, try something like this https://www.inverter-warehouse.co.za/collections/specials/products/zuva-back-up-box-2

not sure if it can get you through the 4hrs of loadshedding though. But you can add more batteries to it as it has an option for external batteries 

You need completely silent inverter. Should be fanless model - check the specs in the datasheet for whatever power you think, you will require (for your needs maybe 2kW will be more than enough).

It would be best, if it supports LIFEPO4 batteries, so buy 2 x 12V LIFEPO4 and a trolley enclosure for them and put the inverter on top.

Edited October 28, 20214 yr by PowerUser

Looks like a good option to consider, thanks. Out of curiosity, which Inverters are silent? Or where to look for one.

15 minutes ago, Pasito said:

Looks like a good option to consider, thanks. Out of curiosity, which Inverters are silent? Or where to look for one.

Not sure which ones are silent. You will have to look at the datasheet and see the noise levels specified there and if it’s fanless design. 

Re-evaluating my needs, probably will land up spending more. 

Stuff like this seems like the way to I guess, from just reading this forum:

Also would it be worth using the "King" inverter instead with the 0ms switchover, or is that not necessary for PC + 3D printers?

Would it be worthwhile getting a 3kVA 24V system paired with a Hubble AM4 with like the KODAK Solar Off-Grid Inverter VMIII 3kW 24V? Or is it not worth investing in a 24V system and spend more and get 5kVA 48V like in the post linked?

Just in terms of noise, how loud would a system like this be, and if it's loud, what needs to be swapped out/modified? I also saw some posts swapping out fans to Noctua's which might be also a good option. 

I recently found out that the sunsynk 3.6kw is fanless, exclusive to SA model, but it is the same price as the 5kw with fan 🤨

The important thing is that you know your loads and the maximum you will need at any given time. I think this is important.

Yeah I've been doing some research, still not sure what to get tbh. Solis also have fanless stuff, but (and my knowledge on the topic isn't great) I think I need the Hybrid one ( https://powerforum-store.co.za/collections/inverters/products/solis-energy-storage-6kw-hybrid-5g-inverter-with-dc-switch) which isn't super cheap. The others I'm assuming are for solar solutions but not battery backup (guess work on my part as I don't see anything in their datasheets relating to batteries).

I woulda thought the use case of being silent for being in an apartment/flat without a garage/somewhere where noise isn't a factor, would be more common. Everytime I look at this it looks like I need to spend more and more 😅

On 2021/10/28 at 1:53 PM, Pasito said:

Any ideas for a starting point (even if it's another thread, just looking for up to date info)

You mentioned what you want to power but please tell how you want to power it.

Example you can split the DB in two and have the inverter only feed what you want to feed.
You can run it like a generator with a switchover switch and manually go over to backup. (Cheapest but presume this is not your requirement with 3D printers etc)

It did cost me about R10k to split the DB and if you put that money towards a larger inverter you can put the whole house on backup while using load controls for high usage items (geyser, stove, etc) to save battery life during power outage.  Less abortive installation cost.

PS  What advantage would a hybrid inverter have if you are not adding solar panels?

I think I'd split it and feed only some breakers, preferably with automatic switchover. I could put everything on though, not an issue as it's just me here so I know not to turn on the stove etc.
 

1 hour ago, Pietpower said:

PS  What advantage would a hybrid inverter have if you are not adding solar panels?

Not sure to be honest, I just don't see fanless options that aren't Hybrid inverters. The other Solis inverters (which according to datasheets are cooled passively) look like they aren't for battery systems and are for just for grid tied solar systems, but maybe I'm not understanding the options well enough. The terminology seems strange but from googling it seems I need either an Off Grid (like the Axpert ones) or a Hybrid. Not because I need a Hybrid/can ever get solar, but just because there's options with passive cooling that don't make a noise.

Correct me if I'm wrong though (or point me in some direction to research).

3 hours ago, Pasito said:

I think I'd split it and feed only some breakers, preferably with automatic switchover. I could put everything on though, not an issue as it's just me here so I know not to turn on the stove etc.

Seems you are mixing options here.

Splitting:
- Do you have enough space in the DB or do you need to add another DB
- Can you do this yourself and issue COC or will you need someone for the COC
- It requires a fair amount of extra breakers and wiring and work even if you do it yourself
- The backup breakers are feeding from the inverter so always on (no switchover)

Switchover:
- Manual.  It is an either/or situation but not both grid power and backup power.
- Not sure if, or how an automatic system will work.
- You have a delay or short interruption in power.
- Don't know of anyone using such an option

Direct or everything on:
- Since everything runs through the inverter your inverter needs to be big enough for the highest load.
- For me with geyser and stove etc that would be 8kW and up. My neighbour does this with two axpert inverters
- The saving on not splitting your DB can go to a larger inverter.

PS Larger inverters normally use 48V batteries while some of the 3kW inverters can be 24V thus saving on batteries if you just want to bridge loadshedding.
Maybe an additional small DB for the backup circuits with a 3kW inverter is the cheapest option for you.
Another option is to install the Inverter close to the load or equipment to be on backup and have an outlet at the inverter using leads to all your equipment. You will then need some floor standing lights or something.

17 hours ago, Pietpower said:

You mentioned what you want to power but please tell how you want to power it.

Example you can split the DB in two and have the inverter only feed what you want to feed.
You can run it like a generator with a switchover switch and manually go over to backup. (Cheapest but presume this is not your requirement with 3D printers etc)

It did cost me about R10k to split the DB and if you put that money towards a larger inverter you can put the whole house on backup while using load controls for high usage items (geyser, stove, etc) to save battery life during power outage.  Less abortive installation cost.

PS  What advantage would a hybrid inverter have if you are not adding solar panels?

Yeah by "automatic" I mean running things through the inverter. But will probably split and just put a few things on it. I won't do it myself, will get someone in. Probably need another DB. Either that or "direct", not switchover.

This part isn't the concern, I get there will be an installation effort and cost. My concern is more finding an appropriate inverter that is silent/quiet and that preferably doesn't break the bank.
 

Agree with the 3kW + small db, just which one won't make a noise, as the only silent options (that I'm seeing at least) are hybrid inverters in the ~R20k range.