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Jackal

Urgent Help: City of CT Cutting Off Axperts

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Hi All, 

I'd really appreciate your advice to help one of our own. A friend of mine who is a recently retired engineer has invested a lot of money in his off-grid system, doing his bit for saving mother earth and reducing his monthly expenses as he eases into retirement. Next thing the City of Cape Town knocks on his door because his monthly bill is so low. His system is comprised of 2x 5kva Axperts, 12x 200AH batteries, small wind turbine and 4KW PV. The City of Cape Town has come to the following conclusions:

  1. Axpert inverters are not on the City’s approved inverter list.
  2. An Off-Grid solution may not in any way be connected to Eskom supply.
  3. Even for an on-grid (grid-tied) solution (with approved inverters) 2x Axperts are over the limit (because its greater than 3.5kva) of what may be deployed in a residence.

It would appear that the laws state as per page 18 of the 'CCT Requirements' document attached you are only allowed to have 3.5kva of generation capacity for a 60A municipal feed. Also attached is a 'SSEG Configurations' document he was provided by the City of CT. With PV generation limitations so small its literally impossible to produce enough even for self-consumption, never mind back-feeding for a rebate. And the Axpert is more of an online UPS with a solar charger so not sure why it would need to be certified by the City of CT because it does not (and can not) operate in any kind of grid interactive fashion. 

His only option to avoid being disconnected is to install a break-before-make rotary change over switch which physically disconnects his renewable systems from his DB boards i.e. when the switch is in the 'Inverter' position the essential loads run totally off-grid with no Eskom AC charging/pass-through support; the Axpert is only allowed to have PV as an input source. When the batteries are depleted all loads turn off. He must then manually rotate the switch to put the essential loads back onto Eskom. When the switch is in the 'Eskom' position his renewable systems are totally disconnected and sitting idle. 

Can this be right? If so, every Axpert in Cape Town connected to PV needs to have its Eskom AC incoming line disconnected to be SANS compliant and avoid risk of the City of Cape Town disconnecting your power. 

Please share any and all ideas and opinions and if anyone is able to help sort this out please send me a private message so that I can connect you with my friend. 

Thanks!

SSEG configurations (2017 04 06).pdf

CCTRequiremenstforEmbeddedGeneration_V47 20161103.pdf

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Probably a load of bollocks with an overeager official. First check with the senior personnel rather than the oke with a pencil behind his ear. If this is true then the only thing I can think of is a 48 V battery charger that would need no compliance and one could charge batteries and draw from the same said batteries. Or a three point plug for a standby gennie.

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The list only applies to embedded generators. The Axpert is not an embedded generator and never can be. If it ever accidentally does so (that is, accidentally latch the transfer switch while the inverter is active), it will simply blow up. So that it isn't on the list is immaterial.

Second point: A UPS is an off-grid solution. A UPS has an automatic transfer switch. Far as I know, you are allowed to connect a UPS to the Eskom grid. There might be some boxes it has to tick, for example, it probably needs an SABS mark or something similar. This is what you have to check.

Third point: Once again, that's for embedded generators. You are allowed to connect a generator to your house, and that is allowed to be larger than 3.5kva, and it may even have an automatic changeover as far as I know.

The only thing you need is a CoC by a qualified electrician.

The challenge is going to be to prove that it is a UPS.

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This topic actually makes me think. If we have a Victron Multiplus installed as a UPS for the office, is it legal? (gut feeling says yes, it must be). If I then add an MPPT and some solar panels, in what way does that change things? The danger (if there is such a thing) of accidentally energising the line in reverse is the same with or without the solar backup, in fact, you can use these inverters without PV panels to do "peak shaving" when they are configured as hybrid (by default they are not).

Do I now need an official PrEng or similar to sign off that it was commissioned as a UPS and that we cannot and will not feed back? Because it sounds to me like that is what might be needed if they want to be consistent about this. There has to be a clear distinction between embedded generators and UPSes. Well... I already thought there was... but I digress.

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Thanks for the feedback so far guys. I share all your sentiments and in my mind all these SSEG regulations applied to grid tie installations. But apparently this is not so and the regulations have been amended to include off-grid (solar charged UPS) installations as well. He has CoC for all his wiring and has sought advice from a PrEng who has provided some support with appeasing the City of Cape Town but was unable to get them to allow the Axpert to stay connected to the AC incoming line. He is an engineer himself so is also pedantic with wiring standards! As I understand the City of Cape Town has sent officials and inspectors to the house on numerous occasions and he is in touch with senior personnel. For now he has bought a 7.5kva diesel generator with an ATS to buy himself some time but this cannot be the solution and plight for everyone who has an Axpert with PV. 

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FYI: Online UPS = runs off its batts 24/7/365. There is no direct connection between incoming Eskom and UPS output. They are pretty expensive and can take just about any volts to charge the batts that in turn powers the inverter. But, and here is the part we never saw coming, cheap generators can damage them too. Just a titbit we saw happening.

http://www.apc.com/us/en/faqs/FA157448/

The issue is not standby/line interactive (?) UPS'es like Axpert / Victron. It is about the ability of the device to feed power back onto the grid. Victron has no SCC built in, so it is a UPS versus the other makes with a built in MPPT.

 

I see CoCT has substantially updated the docs since I last read them i.e. much clearer. :-) 

@Jackal, what their docs say has been consistent since +-2008 when I first started asking questions. The moment you connect said solar system or a generator to a DB board, it becomes an issue. That part has not changed at all. Just got more refined.

UPS cannot never feed power back to the grid ever.

The max generation limit has been around for some time. Problem is we never really had anyone visit any of us as your friend has now experienced. Yes I have heard from various solar installers in CoCT when a clients bill drops substantially, CoCT checks up on that. As a matter of fact. If a installer installs a illegal system, CoCT can make it difficult for them to do business. So the approved installers are doing it by the book.

Now installing a generator or solar panels that is connected to a DB, both can cause issues when the grid comes back online if not installed properly, so yes, their concerns are valid and their rules have been around for a long time.

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3 minutes ago, Jackal said:

But apparently this is not so and the regulations have been amended to include off-grid (solar charged UPS) installations as well. 

Since your friend is an engineer can the COCT senior personnel explain what is their objection off-grid installations. There can be no logical reason and if folk have to make a choice between grid supplied off-grid and totally off-grid they going to lose. Everyone is watching electricity prices until parity is achieved. They are just forcing everyone's hand to jump sooner.

Another alternative is to have a changeover on a timer. and switch what was on inverter over to grid in the evenings and back to solar in the mornings, but what a waste to achieve exactly the same thing.

Next thing you know you will need a certificate to sit in the outhouse - I sympathise with the trekboers, this bull been going on for nearly 200 years.

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If you connect to a DB board, their are regulations. Debating the points are futile, like the Borg, for in my discussion with various people over the years, listening to CoCT explaining in podcasts why when and where, trust me when I say, they have a few jacked up people in charge.

Get hold of Brian Jones
Head: Green Energy
4th Floor
Electricity Services Headquarters,
Bloemhof Street
Bellville

It seems now that even I (this is new), whom have a off-grid solar UPS powering separate circuits, need to fill in forms to confirm it is nowhere connected to said DB.

My loads on separate circuits are powered by a APC online UPS. APC gets is power from either Eskom or inverter, based on SOC of batts. Did it like this is to steer clear of all CoCT concerns.

Interestingly I also see now that if you have an approved solar system installed, and you sell the house, the new owner must sign again with CoCT. Clever, very very clever CoCT. Make sure the new owner is aware of all the rules and regs.

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@The Terrible Triplett Thanks for the more detailed clarification, makes a lot more sense now. What approach are the approved installers taking with Axperts? From you explanation and the City of CT documents the only patterns that are legal would be installing an Axpert as a UPS with no PV source or installing it in a pure off-grid model with no Eskom source? 

@Chris Hobson He's at the point where he has been fighting for weeks and they just won't accept anything other than being totally off-grid or grid supplied. You right, now they losing because my fried has bought a genset and would rather buy diesel than go back to Eskom. 

How about removing the PV from the Axpert and deploy the Axpert as a UPS. Apply for an SSEG self-consumption license. Buy a small (<3.5kva) grid tie inverter for self consumption and connect to all the PV. The Axpert would charge its batteries from the grid (and grid tied inverter). Schedule a contactor to switch to the UPS and cycle the batteries after hours on a timer. 

Are there any other suggestions of how he could adjust his design to comply with the City of CT's regulations but still enjoy the benefits of his investment in PV? 

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Just now, Jackal said:

What approach are the approved installers taking with Axperts?

It it is not on the CoCT list, they will not install it.

 

1 minute ago, Jackal said:

... now they losing because my fried has bought a genset and would rather buy diesel than go back to Eskom.

Sorry for being blunt but this is penny wise and pound foolish. Diesel is like in really expensive compared to Eskom. On a farm yes, in the city never.

 

It is not CoCT's fault. Their regulations have been around for many many years now. As a matter of fact, they have been saying for years now:

It is essential that all customers wishing to install a grid-tied SSEG, regardless of generation capacity, complete the relevant sections of the application process in full, and that written approval is received from the City before system installation commences. The City needs to ensure that, amongst other considerations, the SSEG installation can be accommodated on the electrical network and that the total SSEG generation capacity of the network has not been exceeded. Equipment should therefore not be purchased prior to obtaining written approval from the City as approval is not guaranteed and the City will not be held liable for equipment expenses where approval is denied. A list of inverters which have been shown to comply with the City’s requirements can be found on the City’s website.

 

Your friend needs to read the regulations, and costs, for depending on how he connects it could be more expensive than what he wants to save.

Remember, the problem is not CoCT making, it is a historical international problem in that grids are designed on a national scale, not regional or even suburb scale like Mini Grids. The problem comes in that renewables are not reliable enough and must be managed very precisely or there could be bigger problems down the line. Mini grids or restrictive regulations is what I see the future holds.

If anyone wants to kick Eskom out, by all means go for it, go off-grid. What I learned was respect to the Eskom engineers when one realises the true cost of off-grid and let me tell you, that pales in comparison of the intricacies in the management of said system with SWAMBO and child in said house. :D

Off-grid ONLY makes sense where there is no Eskom.

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15 minutes ago, Jackal said:

How about removing the PV from the Axpert and deploy the Axpert as a UPS.

Because the Axpert has a MPPT, what stops user from connecting it back onto panels after they have agreed to view it as a UPS?

UPS'es as I said before, has been around for decades and can never ever feed power back to the grid. That is why they are approved by default.

Along comes very clever oaks and adds a MPPT controller to a UPS ... and there the wheels came off. 

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19 minutes ago, The Terrible Triplett said:

The issue is not standby/line interactive (?) UPS'es like Axpert / Victron. It is about the ability of the device to feed power back onto the grid. Victron has no SCC built in, so it is a UPS versus the other makes with a built in MPPT.

That's the bit I find a little ridiculous. The fact that it has a built-in SCC doesn't give it magical capabilities. The proof of this is that 1) the Axpert which is a UPS that happens to have an SCC in the same box is now questioned, while the Multiplus which has no SCC in the box (but has the magic capabilities) is exempted.

It would seem to me that the simplest thing to do is put in the change-over switch, get the paperwork done to get them off your back. But now that makes me wonder how you'd install such a change-over. Because it seems to me that the bit that worries them (or should worry them) is the input side. Disconnect it from the grid and the whole thing becomes legal, right?

6 minutes ago, The Terrible Triplett said:

It is essential that all customers wishing to install a grid-tied SSEG

It isn't grid-tied! The SSEG regulations don't apply to off-grid inverters. Other regulations might apply though... that is the thing. They are throwing the wrong book at him.

 

5 minutes ago, The Terrible Triplett said:

UPS'es as I said before, has been around for decades and can never ever feed power back to the grid. That is why they are approved by default.

They still can't feed back even if you do add an MPPT. I know people who added solar charging to existing grid-interactive UPSes so they last longer during load-shedding. And as I said, the irony is that there are MPPT-less inverters that CAN feed back which is now hilariously excluded from scrutiny.

It comes down to this:

1. What regulations do you need to comply with?

2. What do you need to do to be compliant.

It seems to me that what you need to do is disconnect the input of the Axpert from the grid. Do that, get the paperwork done. That way they don't come knocking again because the bill is too low, because you have the paperwork.

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11 minutes ago, The Terrible Triplett said:

UPS'es as I said before, has been around for decades and can never ever feed power back to the grid. That is why they are approved by default. 

The Axpert too cannot feedback to the grid it has an AC charging circuit and a relay switch and basically grid supply passes through the inverter.

Addition: Plonky has covered this much more eloquently. 

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I've asked this question before but... what happens when you only need say 10 Amps AC from Eskom to top off the batteries and have the Axpert on a 3 pin plug.  Add another plug point from the DB to the Axpert location and then plug the Axpert in there.

Will be like running any UPS...

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@The Terrible Triplett Thanks again for more insight! So what I'm hearing is there is no legal way of using an Axpert on a premises where there is an Eskom connection and PV because a) it is not an approved inverter and b) because it is not a UPS but rather an MPPT device. Would you say its considered legal (assuming there is a CoC) for an Axpert to be installed as a 'UPS' on a premise with no PV? 

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13 minutes ago, plonkster said:

That's the bit I find a little ridiculous.

Is it? What stops the user to connect solar panels to it later? I will not trust a guys "word" that he will not connect.

 

13 minutes ago, plonkster said:

It isn't grid-tied!

... disconnect the input of the Axpert from the grid. 

If you connect anything to your DB board, and do note where your electricity is coming from (Municipal OR Eskom for their regs do differ)), there are regulations to meet.

Does not matter what device it is, if it is connected to said DB board, go big (read right) or go home.

 

Really, debating the issues here is interesting, but unless you get approval for connecting whatever your choice of device is, if it is not approved by your local regulator, it is not approved.

It is about safety and making sure every 2nd wanna-be self taught "sparky" does not cause more problems than what they sort, and for that you need regulations, approved devices and installation standards.

You don't like it, tell them to take a hike and grow a huge pair and terminate the grid connection to your house and do your own thing. If not, follow the regs.

 

2 minutes ago, Jackal said:

Would you say its considered legal (assuming there is a CoC) for an Axpert to be installed as a 'UPS' on a premise with no PV? 

I don't know. It is all about connecting to a DB board. Keep it all separate  - Eskom and solar powered - fill in the forms to that effect, and you are good to go I would say.

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11 minutes ago, Mark said:

I've asked this question before but... what happens when you only need say 10 Amps AC from Eskom to top off the batteries and have the Axpert on a 3 pin plug.  Add another plug point from the DB to the Axpert location and then plug the Axpert in there.

Will be like running any UPS...

There are regulations about things being permanently installed, usually not consistently applied. For example, air conditioners are sometimes deemed "not permanently installed" even though it is bolted to the building, and they are often fed from the nearest plug point. Technically it is safe as the max draw is maybe 5kw for a short time (at startup), which is just within the limits of a 25A plug point. I'd think a 5KW inverter is pushing this a bit... especially two of them. Technically they have to be on their own breakers.

Think about the ridiculousness of this... you're now going to make it LESS safe in order to comply.

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Did you guys read this? Electricity Generation & Distribution Small scale embedded generation (SSEG) configurations: 6 April 2017

Is says: 
4. Passive standby UPS utilised as off-grid hybrid SSEG:
This applies to any UPS operation functioning according to the following principle:
a. The normal mode of operation consists of supplying the load from the grid as primary power source.
b. When the latter is outside stated limits, the load is supplied from the UPS inverter, operating in stored-energy mode.
Such a system is regarded as off-grid provided it is equipped with a suitably interlocked change-over switch, selectable as follows:
c. Charger/rectifier mode (normal): Batteries are charged by the SSEG installation or, if required, by the grid. The grid is the primary power source for all the loads. or
d. Inverter mode (when the grid supply is interrupted or applicable electrical service conditions are outside stated limits or required tolerances): The grid supply is disconnected and selected loads are supplied from the inverter, within the rating of the energy storage or SSEG.

EDIT: see point 3 and 5 also of said document.

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2 minutes ago, The Terrible Triplett said:

If you connect anything to your DB board, and do note where your electricity is coming from (Municipal OR Eskom for their regs do differ)), there are regulations to meet.

Yes, but that is SANS regulations, not SSEG. SSEG is about how your equipment might influence/destabilise the grid, not about how your equipment might endanger people in the house and or burn it down (which is a safety thing regulated by SANS). All you need for the DB side is a CoC.

6 minutes ago, The Terrible Triplett said:

What stops the user to connect solar panels to it later?

The panels doesn't matter. Well, maybe it does on the mind of the guy they sent with the pencil and the clipboard, but as I explained already: A multi with no PV attached but incorrectly configured as a hybrid is more of a "danger" than any Axpert.

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5 minutes ago, The Terrible Triplett said:

Such a system is regarded as off-grid provided it is equipped with a suitably interlocked change-over switch, selectable as follows:
c. Charger/rectifier mode (normal): Batteries are charged by the SSEG installation or, if required, by the grid. The grid is the primary power source for all the loads. or
d. Inverter mode (when the grid supply is interrupted or applicable electrical service conditions are outside stated limits or required tolerances): The grid supply is disconnected and selected loads are supplied from the inverter, within the rating of the energy storage or SSEG.

Technically the changeover switch in the Axpert (and in the Multi) complies with this.

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6 minutes ago, Jackal said:

So basically only buy an Axpert if you live in the bush! 

Pretty much as it stands today yes, unless Axpert gets the necessary approval done by the likes of Veritas etc.

I have looked SMA via a approved installer and the regs are pretty straight forward to meet and to get approved. Easy as Pie.

BUT, the issue for me came in that depending on how I do it, I will either have a min bill of +-R600pm OR I use my old meter but then I will lose for unless I use all the solar power when it is there. So I climbed back in my box and use my system as is - off-grid.

 

1 minute ago, plonkster said:

Technically the changeover switch in the Axpert (and in the Multi) complies with this.

Then there is no problem. Install and get the approval. :D

O wait, Victron is approved but you need to install more to make it legit.

SMA, also approved, but if you want to cut off all feeback and use your old meter, then another 5k on top of it all is expected to be spent.

 

I think the question we are debating is the wrong one. The question should be: What is the devices function?
Is is a pure stock standard UPS?
Or is it a device that is designed to do more than just a UPS function?

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Just now, The Terrible Triplett said:

I have looked SMA via a approved installer and the regs are pretty straight forward to meet and to get approved. Easy as Pie.

Getting the inverter certified is a costly exercise, definitely not straight-forward. If you have such an inverter (or the Ziehl as I do), then it is indeed simply enough to do the paper work. 6 things on the list, all of them NRS097-2-1 stuff. They really just want to know that this thing is not going to push back.

The trouble is finding a PrEng that's not going to cost the earth. Rumour has it that a plan is being worked on to make this part simpler. It also depends on what Nersa decides.

Here is a snapshot of the bit you need.sseg.jpg.c51b42900a90df2ae25712acca3776cb.jpg

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8 minutes ago, The Terrible Triplett said:

Then there is no problem. Install and get the approval. :D

The trouble seems to be that the change-over switch isn't "suitably interlocked".

9 minutes ago, The Terrible Triplett said:

I think the question we are debating is the wrong one. The question should be: What is the devices function?
Is is a pure stock standard UPS?
Or is it a device that is designed to do more than just a UPS function?

It doesn't matter what the function is. That is none of their business. What they are concerned about is the impact of your equipment on the grid. I totally understand it, if you have a proliferation of such solar-UPSes and something goes wrong (occasionally, but enough that it is a problem) and that suitably interlocking transfer switch isn't as interlocked as you hoped... well then you have a problem. I don't think it matters what the function is or whether you have PV connected. The question is whether your transfer switch is sufficiently "interlocking", and I suspect that is where you're going to get stuck.

I think it is slightly ridiculous because nobody checks the transfer switches of China-special UPSes... and technically they all pose the same danger.

I have another solution for you though. Install a Ziehl UFR-1001e in front of your Axpert. It is complete overkill, but then it's compliant. Perhaps check with them, but far as I know, that will do it. Rather an expensive add-on, but cheaper than a new inverter.

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