5 minutes ago, Zombie said:

PS. This is CoJ

Me too.

That means that CoT (Tshwane) is charging me around R1.78 per unit. They do not define the cost of "other" charges on the bill.

Would love to hear the costs / unit for other areas, including other areas in Pretoria. 

16 minutes ago, MorneDJ said:

Would love to hear the costs / unit for other areas, including other areas in Pretoria. 

Cpt is R172.5 incl connection fee.
I pay R1.85 incl per kwh because we buy, since we went grid tied and being summer, less than 600 units per month.

Bill varies between +-R600 incl some times, sometimes +-R900 incl, plus the connection fee.
Evening use costing the most..

Here's my postpaid COJ snip. All costs included and usage averaged, it comes to R2.11 per kwh

This is quite interesting. But should perhaps be in a separate thread?

On 2019/04/02 at 3:20 PM, MorneDJ said:

If I go for Victron system, can I drop in another in parallel to give 6 kW to the house should I ever need it ?

on the multiplus you can yeah

After reading as much as I could, including two books on solar, I realized that I know even less than I thought I did. And that the installation is actually slightly more involved than what I imagined, not to say anything about potential regulations in Pretoria (anyone know anything on that, btw?)

Anyway, steaming ahead I ordered 2x Polytechs, that should assist in keeping the lights on at night. Seems that it is the item most difficult to find, and takes the longest to get.

After thinking hard, it appears that I will be batting for the blue team. On that:

- Is there an optimal input voltage and current on the Multiplus II 48/3000.

- Should I plan for 3000W of PV modules, or can I go higher, like in 4000W. The thinking is that I will try and optimize power use at night from the battery bank, and have the excess solar available to assist in the charging of the batteries during the day. If I do not use the excess power will it be to the detriment of the system or will it just be wasted. I may consider dropping in another Multiplus in parallel and use the other pylontech on that one in the long term. 

- With 3000W I can manage with 9x Canadians 335 W, with 3 in series, 3 parallel, giving me a total power of 3,015W. Pretoria seldom get colder than 5 C, so max voltage is not a concern. One Smartsolar 150/70 will do the trick. Alternatively, 5 in series with 2 in parallel giving me 3350 W, using the Smartsolar 250/85?

1 hour ago, MorneDJ said:

After thinking hard, it appears that I will be batting for the blue team.

Welcome ... (in the tone of The Borg - if you can hear them in space) 🙂 

I have recently asked the same question: Inverter is max 3kva (2/4kw). So by how much must I oversize - 3.2kw or 3.5kw. 
Answer is still pending - for as you say, too much and you waste, too little and you can add later.

150/70 or 250/85 - it depends on your budget - 250/85 is nicer ito higher volts but at the end of the day, the losses from all over, is it really that much better?

150/70 with 10mm2 wire and you are sorted.
250/85 and 6mm2 wire and you are sorted.

Anyone else?

I will speak to Wessel from Revolt tomorrow about this. The quote they gave me was for the 12 335w panels, or 4 kW. 

6 hours ago, MorneDJ said:

After reading as much as I could, including two books on solar, I realized that I know even less than I thought I did. And that the installation is actually slightly more involved than what I imagined, not to say anything about potential regulations in Pretoria (anyone know anything on that, btw?)

Anyway, steaming ahead I ordered 2x Polytechs, that should assist in keeping the lights on at night. Seems that it is the item most difficult to find, and takes the longest to get.

After thinking hard, it appears that I will be batting for the blue team. On that:

- Is there an optimal input voltage and current on the Multiplus II 48/3000.

- Should I plan for 3000W of PV modules, or can I go higher, like in 4000W. The thinking is that I will try and optimize power use at night from the battery bank, and have the excess solar available to assist in the charging of the batteries during the day. If I do not use the excess power will it be to the detriment of the system or will it just be wasted. I may consider dropping in another Multiplus in parallel and use the other pylontech on that one in the long term. 

- With 3000W I can manage with 9x Canadians 335 W, with 3 in series, 3 parallel, giving me a total power of 3,015W. Pretoria seldom get colder than 5 C, so max voltage is not a concern. One Smartsolar 150/70 will do the trick. Alternatively, 5 in series with 2 in parallel giving me 3350 W, using the Smartsolar 250/85?

You can definitely install 4Kw of PV as you'll never get 100% of your 3Kw. In fact, on a 3Kw PV array you'll most likely get about 2400-2600w out, depending on many factors - one of the biggest is that your panels get hot during the day and thus under perform. SMA state you can safely install 60% more PV on their inverters. I know someone in Cape Town who installed 21 PV strings on an Axpert inverter, as an experiment. In general adding 20% to 30% more PV is the norm, so on a 3000W PV it would be 600W to 900W. In summer you'll probably get the full 3000W usable energy and waste some. In winter you'll thank me though

4 minutes ago, Pietpower said:

Is it a hybrid inverter

Yes.

TTT thinking, if we all ask these 2 x DA's same type of questions, saying ye we know we not in CoCT but i CoCT is leading and we want to learn from their experience...

Flattery will get you everywhere.

G

1 hour ago, georgelza said:

TTT thinking, if we all ask these 2 x DA's same type of questions, saying ye we know we not in CoCT but i CoCT is leading and we want to learn from their experience...

Flattery will get you everywhere.

G

Yes, I was hoping every single member here on this forum, all installers via their clients, would have sent a email to their local political member asking them what is going on. 🙂 

If that could have generated 500 / 1000 / 10 000 emails, all sent to say DA HO, it would have indicate something is potting to them before the elections, hinting on votes for their participation.

But we don't get what "Unity Creates Power" means - us whities, we don't do that.

If this issue was a ANC / EFF / Cosato interest / ......, it would have been dealt with all over the press with possibly a riot or two, few burning tires thrown in.

But we don't get that ... we don't stand together for our common good - Minority (few making the regs) is leading the Majority here. 

Planning for the installation, the first hurdle is the DB in my house. 

It is installed in the pantry, in a rather inaccessible location. This, is mainly my doing, as it used to be a laundry room that I converted into a walk-in pantry. But now it is covered in shelves, normally covered with ants (eating the honey, peanut butter and nick-nacks spilled by the kids).

So, the best would be to move it, but it is quite a mission, as most of the plugs into the house goes into the ground, and moving the DB completely would require me to connect a bunch of cables to extend. Anyone recommend a way to connect these cables and to isolate each connection. There will not be space for those big connectors that are filled with that epoxy type mix.

Alternatively I can split the DB, installing the EM112 next to the mains switch, and leaving the "non critical loads" where they are and only moving the critical loads. But then the cable linking the EM112 with the inverter will be around 10 m. Would that be possible ?

Here's a completely unrelated tip for ants. Go to the Koop and buy 1 liter of Cypermethrin which will cost you about R150. 1ml in a 1 litre spray bottle is the same concentration of the same stuff in Doom, Dyant and all of those aerosol products. That one liter will last you for years. Google tells me a spray can of Dyant costs R40.

Edited April 16, 20197 yr by DeepBass9

Lol. Thanks. Was joking but I will definitely use that tip.

Solar freedom and ant freedom at the same time. Win win!

On 2019/04/10 at 3:33 PM, MorneDJ said:

Pretoria seldom get colder than 5 C

 

Is this correct?

6 hours ago, VisN said:

Is this correct?

https://weather-and-climate.com/average-monthly-min-max-Temperature,pretoria,South-Africa

https://www.sahistory.org.za/dated-event/coldest-day-pretoria

16 minutes ago, Pietpower said:

Heating load software design temperature gives Pretoria as 2°C which means something like 5 days or 5% of the year it might go below that.

But that said the minimum is also before sunrise thus after sunrise the temperature rises quickly.

I've been using -5 (Midrand) as my min temperature setting and the Victron MPPT calculator rejects most of the modern high power 72 cell panels when you go 3S for my 150/70.

Edited April 17, 20197 yr by VisN

But at that time of the morning your panels will be producing zero. In winter on the highveld you won't produce any power before 8.30, where you might get a few measly watts.

37 minutes ago, VisN said:

I've been using -5 (Midrand) as my min temperature setting and the Victron MPPT calculator rejects most of the modern high power 72 cell panels when you go 3S for my 150/70.

The lowest recorded temperature in Gauteng was -9.4 °C, measured in Vereeniging on 09 July 2014. - clear skies, so its quite possible with early morning temps and sunlight.

Closer to the coast you are probably OK.

Edited April 17, 20197 yr by phil.g00

9 minutes ago, DeepBass9 said:

But at that time of the morning your panels will be producing zero. In winter on the highveld you won't produce any power before 8.30, where you might get a few measly watts.

But, it isn't about watts, it's about voltage, open circuit voltage is 0 watts by definition. 

Edited April 17, 20197 yr by phil.g00

So put some load on that and your voltage will drop pretty promptly. There is another thread currently about why solar panels never produce their rated capacity. In a real world situation in south Africa on the highveld, you will not be producing any appreciable amount of power before 8 to 9 in the morning and the sun will heat the panels to well above 5 to 10 degrees pretty quickly.

Edited April 17, 20197 yr by DeepBass9

11 minutes ago, DeepBass9 said:

So put some load on that and your voltage will drop pretty promptly. There is another thread currently about why solar panels never produce their rated capacity. In a real world situation in south Africa on the highveld, you will not be producing any appreciable amount of power before 8 to 9 in the morning and the sun will heat the panels to well above 5 to 10 degrees pretty quickly.

I grant you that once loaded it would drop the voltage, I also grant you that that is the most likely scenario.

But I can think of reasonably expected scenario's where that wouldn't apply. ( And obviously the MPPT manufacturers can as well).

We are only talking about the tiniest pinhole breakdown in an electrical component, like a flash of static from your feet on a carpet.

Once there is a way for a component to track, that component will break down  and fail when it is asked to work.