Hello all

Brought here by Eskom and it's uselessness as I'm sure most have.

 

I'm looking into an inverter setup to power my home theatre PC, my TV and my router for the now 3 sessions of 2.5 hours load shedding Cape Town gets every day.

 

Can anyone point me in the right direction for a quality setup?

 

Any advice/assistance is greatly appreciated.

Welcome Snorlax

5 minutes ago, Snorlax9987 said:

I'm looking into an inverter setup to power my home theatre PC, my TV and my router for the now 3 sessions of 2.5 hours load shedding Cape Town gets every day.

Get a 2.4kw UPS with 2 x 105ah leisure batteries - expandable to 4. 🙂 

Price < R8k with battery box for the 2 x 105ah batteries.

Thank you for the reply. Any suggestions on reliable models/brands?

All over, friend send me this ad below last night asking my opinion. They are modified sine wave inverters, cheap but does the job.

More expensive alternative is a Axpert with batteries.
And future proofing, get a Victron Multigrid ... because once you start, there is no turning back: You are going to get grow into panels. 🙂  Been there, done that. 

Should I be worried about modified sine wave Vs true sine wave invertors? Will modified damage my appliances?

22 minutes ago, Snorlax9987 said:

Should I be worried about modified sine wave Vs true sine wave invertors? Will modified damage my appliances?

Depends what appliances. Most LED televisions, lights, cell phone chargers, etc already have a switch mode power supply built into them and the very first thing an SMPS does is to convert the AC to DC. These appliances don't care one bit what the waveform looks like.

The things that don't like square wave are small electric induction motors (fridge, freezer, pressure pumps, etc), and microwave ovens. Even those will generally operate just fine on modified sine wave, but they will run a bit hotter.

6 hours ago, Snorlax9987 said:

I'm looking into an inverter setup to power my home theatre PC, my TV and my router for the now 3 sessions of 2.5 hours load shedding Cape Town gets every day.

Let me be a bit more specific.

I have a Yamaha RX-V350 AV receiver (old, but bullet proof). This has a big iron transformer (not a switch mode power supply). I would not use square wave on this unit, even though it will likely handle it fine, because square wave on such an appliances tends to create an audible 50Hz hum. My television (samsung LED), and the DSTV boxes have SMPSes and won't care. The Router will have a little wall-wart which is likely an SMPS, so that is not going to care either.

So the home-theatre system might be something to watch out for.

Will a PC be affected by this plonkster? My home theatre system is just a desktop PC with TV as a screen

6 minutes ago, Snorlax9987 said:

Will a PC be affected by this plonkster? My home theatre system is just a desktop PC with TV as a screen 

PC has an SMPS. It won't care. In fact most UPSes for PCs are modified sine-wave.

Thanks! I've read that the Mecer inverters have a loud and persistent fan noise, what brand would you advise for more silent operation? 

9 minutes ago, Snorlax9987 said:

Thanks! I've read that the Mecer inverters have a loud and persistent fan noise, what brand would you advise for more silent operation? 

If you just want a UPS, then get a UPS as TTT suggested (then you're playing in the <10k price bracket). Once you move into solar territory, I will always advise that you look at a Victron Multiplus-II (now you're playing in the 10k-20k bracket... before you've bought batteries).

Before I continue, I'd just like to thank you for being so helpful and informative.

 

So the Victron would need batteries to act as another inverter in my house, and that is then combined with solar panels to charge it when there's no Eskom power or if I'd prefer to not use Eskom at all, correct?

 

How does one calculate what number of batteries you'd need to power your house comfortably?

 

 

Start with your power bill to give you kWh/day. Then cut that in half by being power efficient. Once you have achieved that you can work out how many batteries you will need. It is cheaper to be efficient, rather than overspend on solar equipment.

From my calculations I use between 280-380 kWh per month.  That's about 10- 13 per day. Not sure if I'm doing it right but that's what I get.

Edited March 19, 20196 yr by Snorlax9987

26 minutes ago, Snorlax9987 said:

that is then combined with solar panels to charge it when there's no Eskom power or if I'd prefer to not use Eskom at all, correct?

You can install the inverter just with a battery bank and use it like a UPS.

Then you can add a solar charger and some solar panels, and do some programming on the inverter to do "self consumption".

As for the rest, I agree with @DeepBass9. The first step is to reduce consumption as much as possible. That reduces the size of batteries and PV modules you need to cover them.

41 minutes ago, Snorlax9987 said:

From my calculations I use between 280-380 kWh per month.  That's about 10- 13 per day. Not sure if I'm doing it right but that's what I get.

OK, that's not too bad, its about what I power off grid, what I have is below on my signature.

13 minutes ago, DeepBass9 said:

OK, that's not too bad, its about what I power off grid, what I have is below on my signature.

And how much did your setup cost?

About R100k more or less, lots of things are cheaper now though.

So say R50k batteries, R15k inverter, R30k panels, + R5k for odds and ends and installation. This was a DIY job though.

Edited March 19, 20196 yr by DeepBass9

3 hours ago, DeepBass9 said:

R50k batteries,

And THAT is my personal nemesis ... batts being the biggest determining factor of the price difference between NEEDS vs WANTS .

I'm struggling to move off 24v as with a 24v bank, and mine MAY have an issue, replacing it  - because we manage our NEEDS - is 50% cheaper than a 48v bank.

And yes we do boil the kettle / use the microwave during at night during failures by switching off the 300w odd draw of PC's with dual screens during load shedding. TV and QNAP still works.

Have elected to set ESS to always keep batts charged so now it is open taps during daytime, where the savings are. 🙂 

The 2.1kw array - another struggle  - am waiting on winter to make that decision to add 2 more panels. 😉 

 

EDIT: Yes Pylon's are cheaper per kwh but I've hjad it with batts. No matter what I buy batts are going to go.

So I'm toying with the idea to go cheap "deep cycle leisure batts" and only use them IF there are nightly failures. 250 cycles is more than enough methinks. 

And basta this coddling of the batts. USE THEM!

Edited March 19, 20196 yr by Guest

On 2019/03/19 at 11:03 PM, plonkster said:

PC has an SMPS. It won't care.

Don't a lot of them have PFC stages today, for European rules? I doubt they'd be impressed with "modified "sine" " waves.

6 hours ago, Coulomb said:

Don't a lot of them have PFC stages today

I haven't done much hardware since around 2007(ish), you may well be right.

7 hours ago, plonkster said:

I haven't done much hardware since around 2007(ish), you may well be right.

I used to have and use a cheap and nasty Mecer square wave inverter.

Laptop charger, LCD TV, LED bulbs all were quite happy on it.  

... Question, I see 50K for batteries.

Then looking around a 120 Ah battery from CSB is R1500/each

Now the numbers don't add up for me, most people running 10-12, maybe 16 batteries, at R1500, even at R2k, thats still way off form R50k.

What am I missing.

G

 

You need to look at how many cycles (discharge and recharge - days essentially) that the battery will supply. Cheap lead acids will give you 500 maybe? Solar batteries like AGMs and lithiums will give you thousands of cycles. I am hoping to get 8 years use from my batteries. 

It also depends on the application. If it is for load shedding type of use where the batteries are only discharged occasionally ( 😯 ) cheaper batteries for standby may suffice. If you are off grid and are permanently either on solar of battery, you need something more robust.

Edited March 22, 20196 yr by DeepBass9

1 minute ago, DeepBass9 said:

You need to look at how many cycles (discharge and recharge - days essentially) that the battery will supply. Cheap lead acids will give you 500 maybe? Solar batteries like AGMs and lithiums will give you thousands of cycles. I am hoping to get 8 years use from my batteries. 

So I'm looking at the CSBB HRL 12390W's which I believe is not a BAD battery.

Looking at the specs, can't see the ah and cycle values... believe the ah =120
G