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New Micro grid system on BYD batteries going in @ 11.6kWp


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Warning, Danger. ⚠️ 

The +- markings on the Noark DC breakers are wrong. Do NOT follow the making to wire them. The red arrow points to the correct flow indicating how the switch connections are done internally. The wiring colours used in this picture is indeed correct.

898629B4-388E-4540-BE69-0B4B688CD302.thumb.jpeg.e9ed60754d98949ac037ee224149e440.jpeg

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11 minutes ago, Sarel said:

Warning, Danger. ⚠️ 

The +- markings on the Noark DC breakers are wrong. Do NOT follow the making to wire them. The red arrow points to the correct flow indicating how the switch connections are done internally. The wiring colours used in this picture is indeed correct.

898629B4-388E-4540-BE69-0B4B688CD302.thumb.jpeg.e9ed60754d98949ac037ee224149e440.jpeg

Seems like there was a bit of discussion on the wiring of DC CB's in the past:

 

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So the Cleptocracy continues…. Another Escam price hike of 15%! The Cleptocracy snowballs, the idiocy continue apace!

 

In 2001, Eskom was named the Financial Times Power Company of the Year at the Global Energy Awards Ceremony in New York.

It was described as "providing the world’s lowest-cost electricity, while at the same time making superior technological innovations, increasing transmission system reliability, and developing economic, efficient and safe methods for combustion of low-grade coal."

 

Post-1994, Eskom embarked on a massive electrification scheme, connecting townships and households that were not connected to the national grid during apartheid. In 1995 alone, the power utility connected more than 300 000 households.

In its annual report John Maree, the then chairperson of the board, restated the company’s mission: to force down the price of electricity for consumers. In Maree's words, the company was "admired internationally" and "a pillar" for the country’s economic growth.

 

Today its debt levels of R430bn represent about 15% of the state’s total debt, debt from municipalities are growing by R1bn per month, and its wage bill has exploded from R9.5bn annually in 2007 to R29.5bn in 2018. That would be R 686 046.00 per person per year on average!

There has been a "significant loss of critical skills", with "poor quality of maintenance" and "poor workmanship" causing breakdowns, of which 40% is due to human error, according to Gordhan.

 

Tshwane Metro currently charges electricity tariffs for residential users according to four blocks:

  • 1 to 100kWh – 170.3 c/kWh (excl. VAT)
  • 101 to 400kWh – 199.3 c/kWh (excl. VAT)
  • 401 to 650kWh – 217.1 c/kWh (excl. VAT)
  • More than 650kWh – 234.9 c/kWh (excl. VAT)

As the sales continues to decline, mostly due to bad service and prie hikes, the sales continues to fall.

  • 5EEF5DB3-AD09-42B6-B936-1CC2633E85DE.thumb.jpeg.f9fe390493f1d7778cdfd8b75c836ae5.jpeg

CSIR from 2019, and we had another about 30% increase since then.

3D1AD53C-22E3-41F1-96F3-0F86553F64DB.thumb.png.d9c324e97fd3e388876487d1daba3c84.png

This is the cumulative increases together….

17B84205-D8DA-4C68-958E-91D70C31763D.thumb.png.29b0c7ae9a76f494a77125050c14274d.png

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On 2021/09/11 at 7:43 AM, Sarel said:

Warning, Danger. ⚠️ 

The +- markings on the Noark DC breakers are wrong. Do NOT follow the making to wire them. The red arrow points to the correct flow indicating how the switch connections are done internally. The wiring colours used in this picture is indeed correct.

898629B4-388E-4540-BE69-0B4B688CD302.thumb.jpeg.e9ed60754d98949ac037ee224149e440.jpeg

So it transpires that the Noarc polarity indicating +- signs are really really badly designed, at the input side they mean positive and negative, but the same symbols on the load (output) side does not mean positive or negative at all! How the actual f can any sane engineer butcher a standard and universally recognised symbol to mean two different things, on the same equipment at the same time? Very dangerous indeed! Very bad UI design, no wonder in some parts of the World, there are now verboten and only non polarised DC brakers are acceptable.
 

The connections are polarity sensitive and directional. Don't be caught out by them markings like Sparky and I was caught out. Luckily we picked this up before powering on, so beware.

Here its connected correctly. Outer side connections are panel inputs and colour coded correctly. The load is connected to the center two poles and is the output.

24E2C18F-0269-46F0-A05F-ACC174425FAE.thumb.jpeg.aa410c6b66d4ccf9f827a8ec69b2eae8.jpeg

 

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On 2021/07/22 at 12:06 PM, Sarel said:

First some background, then I will dig into why and how: After having being an independent consultant to Eskom (Escam) for 10 years till end 2014, I do have some insights into that place. I will leave that there. Since the recent announcement by DeRuyter that the Coal fired Plant will get less and less maintenance (also look at the LHS and RHS graph from Escam data below) its clear we have collectively, a very big issue on our hands.

IMG_1443.thumb.jpg.da9297a09af6e10dc41a092b934acdf4.jpg

 

 

 

….

Sorry, I know it's been a while, but what is this telling us exactly? OK... the red line looks like unplanned outages as % of total capacity. But the green line? That's a %age of what?

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Effectively the availability as a % of total generating capacity. Over the years the total capacity that can be used to generate power are declining (green). Think of this as units in the fleet that are broken and never repaired, so they are still part of the original capacity but no longer capable of generation.

The red line is units down (% of total units) that are down due to being broken and not taken down for maintenance or planned ahead of time.

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On 2021/09/11 at 8:52 AM, Sarel said:

Tshwane Metro currently charges electricity tariffs for residential users according to four blocks:

  • 1 to 100kWh – 170.3 c/kWh (excl. VAT)
  • 101 to 400kWh – 199.3 c/kWh (excl. VAT)
  • 401 to 650kWh – 217.1 c/kWh (excl. VAT)
  • More than 650kWh – 234.9 c/kWh (excl. VAT)

That's expensive! Well... it's more than COJ pre-paid per unit. Is this pre-paid or post-paid? What are the fixed costs? Currently I am on COJ prepaid, no fixed costs for the connection (thought that is surely coming), lower per kWh costs and broader bands. The lowest priced band is 0 to 350 kw/h in the month @ 169.69 c/kWh. And us pre-payers pay more per kw/h than post paid users do (but we avoid the fixed fees for the connection). 

There's no real reason why a solar system should cost more in Thswane than in Joeys, and so it's a better proposition in terms of cost recovery.

 

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Tshwane promulgated tariffs

There appears to be no fixed monthly connection charge. Its credit metering, not prepaid. Nothing is indicated as such on the bill nor on the document referred to above for single phase residential. There are charges for 3 phase tho.

 

Edited by Sarel
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4 hours ago, Sarel said:

So it transpires that the Noarc polarity indicating +- signs are really really badly designed, at the input side they mean positive and negative, but the same symbols on the load (output) side does not mean positive or negative at all! How the actual f can any sane engineer butcher a standard and universally recognised symbol to mean two different things, on the same equipment at the same time? Very dangerous indeed! Very bad UI design, no wonder in some parts of the World, there are now verboten and only non polarised DC brakers are acceptable.
 

The connections are polarity sensitive and directional. Don't be caught out by them markings like Sparky and I was caught out. Luckily we picked this up before powering on, so beware.

Here its connected correctly. Outer side connections are panel inputs and colour coded correctly. The load is connected to the center two poles and is the output.

24E2C18F-0269-46F0-A05F-ACC174425FAE.thumb.jpeg.aa410c6b66d4ccf9f827a8ec69b2eae8.jpeg

 

Yes, this is a really ambiguous design for something that has absolutly no room for ambiguity. I was going to comment on your previous picture of this breaker to say I suspect the two red wires should be switched around, but I see you've changed it.

So even though the breaker has four switches, it in reality only breaks two inputs? What is point/benefit of having two internal switches per input or is just to distribute the high voltage and subsequent arc on disconnect over two switches?

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Yes indeed only 2 inputs allowed. Basically to get enough separation and allow extinction of the arc for voltages up to 1000V DC. In this case the 2 pole version is rated to 500V and the 4 pole to 1000V.

The directionality comes from the magnetic arc extinguishing capability. If you reverse the energy flow direction, you will burn up the switch as the magnets will direct the arc not into the arc chute but into the mechanism.

If I did not catch my incorrect wiring, as in first picture, all my switches would have been destroyed on the first trip or when manually opened under load!

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This 2019 CSIR report will make your eyes water

One extract, actually the lowlight and it’s not even a graph. The CancER knows the answer, it was presented to them on numerous occasions. Politically it is unpalatable as it will make their political and ideological opponents independent from their control. It will also not allow them to rescue the SOE’s and divert the tax paying (not their voters mostly) public’s money into the Escam and other SOE’s without scrutiny.

see the first entry under block 1. And then consider that Tshwane will offer 11 cents per kWh for feed in. Also consider all the hoops and money to be spent to get approval to be robbed blind, again….

C5A61474-2CCB-4EFB-88E3-9E5F73BDE508.thumb.png.7e9b5322603904793235ec7148a257f7.pnghttps://arepenergy.co.za/wp-content/uploads/2020/02/81125_rs_setting_up_for_2020.pdf

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1 minute ago, Basil Katakuzinos said:

Hi, not sure if this has been asked or answered before. What made you chose a quattro over a multiplus ii?

Not the price 🤑….  Because of the way I planned to build the Micro grid, the Quattro has a second AC input, absent in the Multiplus, and the Quattro burst capability is better than the Multiplus.

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18 minutes ago, PowerUser said:

@Sarel, why would you choose polarized DC circuit breakers vs non-polarized ones? Is there anything better with the polarized?  

I was looking for a combined circuit breaker and isolator and for it to fit on a din rail in a db board enclosure. This was the only one that could switch 1000V DC and in stock at the time. So kinda wasn't a choice…. It was the only type available.

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15 hours ago, Sarel said:

I was looking for a combined circuit breaker and isolator and for it to fit on a din rail in a db board enclosure. This was the only one that could switch 1000V DC and in stock at the time. So kinda wasn't a choice…. It was the only type available.

I used some 600v breakers from Onesto although I see you can get them in 1000v as well.

The markers on this breaker seem to be laid out much better. Usually you can get them from Voltex quite easily - 48 hour turn around

 

https://mce.co.za/product/four-pole-6ka-dc-circuit-breaker/

kc6-ld-4.jpg

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Now the Cerbo GX is mounted with the din rail kit. The DB board slot is just perfectly sized to see the Cerbo status lights. A wee bit OCD 🤫, but like only just….

The MPPT charge controller exposed screws are covered and cables tied down with strain relief to protect from shorts. All the DC bus bar inputs are now fused. The only remaining issue will be to make a custom cover for the Quattro feed leads on the left side of the busbars as the lugs will be exposed. Dont yet know how I want to cover that.

Ethernet 1GbE wired for all the devices and talking to the Web. In the process I strted up and commissioned the BYD battery bank successfully, to confirm comms.
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Now look, you get good quality products, good enough quality products and really really kak products. Case in point, MC4 style connectors. The originals are really really good. Some aftermarket ones are kak, plein en simple. We discovered this when one string measured 0 volts after plugin. The feeder cable connecter was fooked, on of the kak connectors.

Staubli are the original ones. The other connector is by Onesto, go figure. The worst part is there is very little price difference….C6A22598-F649-4D57-9254-42AF2831F623.thumb.jpeg.490f92e4c77b29015e046f4659a16089.jpegC7D99D51-9075-4062-8CB0-F6BE1A68B693.thumb.png.181e0ef881dd2539c823ac50614c7d44.png

 

I also made an oopsie in getting my Solar wiring pairs mixed up with 2 pairs. We did a sanity check and discovered. My high voltage string was connected to the low voltage MPPT charge controller. We discovered this before switching on fortunately so the blue Victron smoke did not escape.

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Today was PV activation day, and battery cable day, most of it done 💯 

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I made 3 pairs of battery hookup cables and connected them all to the DC bus. As I have only two towers currently, the 3rd set will stay in the trunking until I get the 3rd tower later.  With them hooked up, there is no need to shut down the system to hook up the 3rd pack later, and no need to mess with cables or busbar connections then, much lower risk this way.

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