3-phase Design Quandry

[zapatero]

Through my own inexperience with Thai electrical design and installation standards, (and probably, more correctly, my own naivete), I have gotten myself into a quite uncomfortable position. (And perhaps all meanings of that last word are appropriate).

I am in the process of building a home in which I need to include 3-phase GFCI/RCD/RCBO protection. Until now, I have been diligently trying to prepare myself for a role of "quality assurance inspector" for my electrical installation, by studying all of the related posts in this forum, (including the excellent Crossy/Elkangorito site); as well as the Square D/Schneider/Safe-T-Cut/7-A/Quin-L/etc., etc. sites. But now, I am slowly coming to the realization that my electrician, (who comes with my building contractor), is expecting me to play the role of system designer. And, unfortunately, thus far I have been unable to locate anyone in my town who can help me with design guidance on these components.

So far, I am pleased with the work that the electrician has done, but he is not an electrical engineer. So far, he has installed most of the electrical conduits, (very neatly, BTW), and the switch and plug boxes, but has yet run no wires. Thus, the circuits have not yet been defined, (except in his head) and the amperage load has not yet been calculated. He has not yet selected a Consumer Unit/Distribution Panel, and certainly has not identified the appropriate GFCI/RCD/RCBO components. In summary, I feel confident that he would be comfortable with a standard single-phase system, with Square-D RCBO switches, or, say, a Safe-T-Cut front end; but I am now not confident that he is comfortable with selecting the appropriate components for 3-phase.

Finally, to complicate things further, 3-phase is still unavailable at our location, so I have chosen to have the electrical system wired as "3-phase-ready"; but to "tough it out" and live with single phase only until 3-phase becomes available. The electrician says that he is comfortable with these interim modifications.

Finally, more finally, based upon the above, can someone with more experience than I please help me to rough out some Consumer Unit/GFCI/RCD/RCBO configuration options, using compatible components that are available here in Thailand? I will gratefully accept any guidance, complete or incomplete. (I realize that there are yet still many questions to be answered from my end; but still, any specific, tentative, make and model numbers would be very helpful.)

Thank you very much for any assistance,

~~ zapatero

[elkangorito]

Has a Maximum Demand calculation been done to verify the size of your supply mains? Also, this calculation is useful for balancing the 3 phases.

[zapatero]

Has a Maximum Demand calculation been done to verify the size of your supply mains? Also, this calculation is useful for balancing the 3 phases.

Hello elkangorito, thank you for your reply.

No, it has not been done yet. I realize that this is one of the first necessary steps, but we haven't yet, (for example), even agreed on the size of the air conditioners. Thus, I know that I am getting ahead of myself, but I am just trying to learn as much as I can before I get there. (I have a habit of falling into holes while looking in the wrong direction.)

If I can learn some specific components that will (probably) work for my situation, then I can research them to understand their purpose. For example, Schneider says that I can use their "accessories model QO-CON1PH" with their Square D load center, to modify it from 3 phase to single phase. Does this seem like a practical option to you for the interim?

And, as another example, since Square D only has single-phase RCBOs, should one attempt to use these with the above "accessory", or does one need to look to a different brand RCD/GFCI?

(Or do I need to wait until the MD calculation has been done to even ask these questions?)

BTW, I read somewhere in one of the posts that you and/or Crossy were going to do an MD calculation writeup. But I've never found it. Can you please give me a link?

[Crossy]

A few disjointed thoughts

A while back Elkangorito produced this document on maximum demand estimation, it's based upon the Australian regulations so it's well suited for our climate in sunny Thailand.

Maximum_Demand_Estimation.doc

Once you have a list of the major appliances and a rough guestimate of how many lights and outlets you will have you can decide how to split the load between phases. Balance does not need to be exact (it never will be anyway). You may even decide that you don't really need 3-phase

Treat your installation as three independent single-phase systems, that means your electrician will be comfortable with something he understands. You could use three consumer units, one for each phase with a single 3-phase incoming breaker as the main isolator. This can all be installed and wired to the single incoming phase.

Obviously you won't be able to use 3-phase appliances as you will actually only have a single-phase supply (at least initially).

[elkangorito]

My comments in blue.

No, it has not been done yet. I realize that this is one of the first necessary steps, but we haven't yet, (for example), even agreed on the size of the air conditioners.

As long as the A/C units do not use more than 10amps each, a Max Demand calc can still be dome. I assume the A/C units are for average size rooms?

If I can learn some specific components that will (probably) work for my situation, then I can research them to understand their purpose. For example, Schneider says that I can use their "accessories model QO-CON1PH" with their Square D load center, to modify it from 3 phase to single phase. Does this seem like a practical option to you for the interim?

I searched for this component on about 3 Square D sites & couldn't find it. I'd forget about it for now.

And, as another example, since Square D only has single-phase RCBOs, should one attempt to use these with the above "accessory", or does one need to look to a different brand RCD/GFCI?

Merlin Gerin have 3 phase RCCB's (4 pole) that will do the job. However, I see no reason for you to need one.

(Or do I need to wait until the MD calculation has been done to even ask these questions?)

Yes. You should do the MD calc first. You cannot really tell anything about the size of your consumer unit, incoming mains etc without this calc.

A while back Elkangorito produced this document on maximum demand estimation, it's based upon the Australian regulations so it's well suited for our climate in sunny Thailand.

Maximum_Demand_Estimation.doc

I forgot about that doc. Where was it?

Anyway, if you need more detail in your MD calc, give me a shout & I'll help.

With regard to your consumer unit, you can connect the 3 internal busbars together & then supply them with the single phase. When you get 3 phase installed, remove the shorting links & you're back in business.

BTW, be sure to have some form of isolation/protection on the line side of the consumer unit...ideally a BS1361 HRC fuse or an appropriately rated circuit breaker. Thai electrical people seem to totally disregard this matter on many occasions.

Edited September 26, 2009 by elkangorito

[zapatero]

Thank you Elk and Crossy. I see that I still have a lot to learn.

I'm taking a crack at the Max Demand calculation, based upon your document. This will take a bit of time, so I will return when I have some numbers.

BTW, I also tried many searches to find that QO-CON1PH "accessory", but no joy. (It was Schneider that recommended it, via email.)

Thanks again,

~~z

[elkangorito]

Max Demand & phase balance calcs now finished. The results are in the attached pdf.

Zapatero_Final_MD_and_Load_Calc.pdf

The only 3 phase switchgear you will have is the Main Switch. Everything else will be single phase.

Each RCBO will take up 2 pole spaces. Each circuit breaker will take up 1 pole space. A pole space is 18mm.

Knowing this & if you choose to follow my recommendations, you will need a 36 pole, 3 phase distribution board (12 poles per phase). The next size up is 48 pole.

I calculate your CB/RCD distribution as follows;

A phase - 8 poles used.

B phase - 11 poles used.

C phase - 10 poles used.

The Main Switch is not included in this count. Main Switches are usually separate & do not take up pole spaces since there is usually a special slot for them (above the CB's).

Your distribution board will look something like this;

http://www.heinemannelectric.com.au/datash...ntage_range.pdf

RCBO's are available in 1, 2 & 3 phase versions. Merlin Gerin make a "Multi-9" series. See below;

http://www.squared.com/us/products/circuit...gfpFrameset.htm

Edited October 8, 2009 by elkangorito

[opalhort]

is this the link you tried to post?

Here

opalhort

OK I just saw the link changes when you use the link up-loader in TV.

I'll try again

Edited October 8, 2009 by opalhort

[elkangorito]

RCBO's are available in 1, 2 & 3 phase versions. Merlin Gerin make a "Multi-9" series. See below;

http://www.squared.com/us/products/circuit...gfpFrameset.htm

Here is the above link again (below). Manually go to the page by copying the link & removing the end brackets, then past it into the URL bar in your browser.

[http://www.squared.com/us/products/circuit_breakers.nsf/unid/AC153DA8D6DB8C508525711000770F10/$file/multi9gfpFrameset.htm]

[opalhort]

RCBO's are available in 1, 2 & 3 phase versions. Merlin Gerin make a "Multi-9" series. See below;

http://www.squared.com/us/products/circuit...gfpFrameset.htm

Here is the above link again (below). Manually go to the page by copying the link & removing the end brackets, then past it into the URL bar in your browser.

[http://www.squared.com/us/products/circuit_breakers.nsf/unid/AC153DA8D6DB8C508525711000770F10/$file/multi9gfpFrameset.htm]

Yes, I just found this out as well. Looks like TV fouls up some links we post.

opalhort

[elkangorito]

"Teething problems" I hope

[zapatero]

It looks like I arrived late to the party, sorry. I wish to publicly thank elkangarito for his Maximum Demand calculation work, 5 posts up. He put a lot of effort into that, and was very patient and considerate with some of my dumb questions.

Hopefully, this project will all come together more clearly once I have gotten through it. But I'm sure I will have to ask some more dumb questions here before it is finished. Beware!

Thanks again!

~~z

[elkangorito]

My pleasure Zap

I/we await your questions, none of which were ever dumb.

[tjo o tjim]

Treat your installation as three independent single-phase systems, that means your electrician will be comfortable with something he understands. You could use three consumer units, one for each phase with a single 3-phase incoming breaker as the main isolator. This can all be installed and wired to the single incoming phase.

Obviously you won't be able to use 3-phase appliances as you will actually only have a single-phase supply (at least initially).

Hands down, this is the best approach for the OP's situation, but it doesn't provide a (safe) means to ever hook up 3-phase loads. You are best off putting in a main panel that is three phase with a main, with three single-pole breakers and space for a few 3-pole breakers in the future.

Also, as Crossy infers, each of the single-phase consumer units can have its own RCD, saving some hassle. You do need to make sure that the consumer unit is not trying to bond neutral and ground though, as this will cause circulating ground currents between the three units.

If you take this approach, be careful to color-code or label everything so you know which phase is where. It can become quite a mess later.

[zapatero]

Hello Folks,

I'm still struggling, but things are becoming a bit clearer.

elkangorito, I have some questions for you please:

1) To help me get my head around all of this I have done up a rough Excel spreadsheet (attached) that contains data from you, that attempts to arrive at (duplicate) your CU pole count. I've come pretty close, but I'm one pole greater than you in the Phase A. Could you please look at it and tell me where the discrepancy is? (I think it probably has to do with the kitchen(?))

As you will see, I have started with your spreadsheet, but have added some more things to help my understanding. This then has led me to some more questions:

2) The air conditioners are not explicitly shown on your spreadsheet. From our earlier discussions I interpret that these have been implicitly included within the "Socket Outlets", even though they will be hard-wired. Is this correct?

3) Whereas, the 3 shower water heaters are listed explicitly, and will also be hard-wired. Thus I am confused re why you have handled them differently on your spreadsheet.

4) In your spreadsheet discussion notes, to assure that I am absolutely clear, may I assume that when you say "RCD", that you mean MCB + RCD = RCBO? Whereas, [excluding the Main Switch], when you say "circuit breaker", that you mean only an MCB? (I'm sure that these are trivial questions; but I want to be absolutely sure that I myself know what I'm talking about, before beginning an 8 hour R/T trip to talk to a Thai salesman who has absolutely no idea what I am talking about.)

FYI, tjo o tjim, thank you for your input -- I'm not ignoring it, I'm just trying to be sure that I understand elk's concept first...

Max Demand & phase balance calcs now finished. The results are in the attached pdf.

Zapatero_Final_MD_and_Load_Calc.pdf

The only 3 phase switchgear you will have is the Main Switch. Everything else will be single phase.

Each RCBO will take up 2 pole spaces. Each circuit breaker will take up 1 pole space. A pole space is 18mm.

Knowing this & if you choose to follow my recommendations, you will need a 36 pole, 3 phase distribution board (12 poles per phase). The next size up is 48 pole.

I calculate your CB/RCD distribution as follows;

A phase - 8 poles used.

B phase - 11 poles used.

C phase - 10 poles used.

The Main Switch is not included in this count. Main Switches are usually separate & do not take up pole spaces since there is usually a special slot for them (above the CB's).

Your distribution board will look something like this;

http://www.heinemannelectric.com.au/datash...ntage_range.pdf

RCBO's are available in 1, 2 & 3 phase versions. Merlin Gerin make a "Multi-9" series. See below;

http://www.squared.com/us/products/circuit...gfpFrameset.htm

Phase_MCB_RCBO_Distribution.xls

[zapatero]

RCBO's are available in 1, 2 & 3 phase versions. Merlin Gerin make a "Multi-9" series. See below;

http://www.squared.com/us/products/circuit...gfpFrameset.htm

elkangorito: I surely must be missing something that is obvious to everyone else. When I read your link referenced above, I find no mention of overcurrent protection. Doesn't that mean that this(these) items are straight RCDs -- i.e., not RCBOs? Therefore, in your concept, wouldn't one also need additionally an MCB in each of your RCD'd circuits, in order to provide overcurrent protection?

[elkangorito]

Zap.

I'll put something together for you very soon...give me a couple of hours.

[elkangorito]

1) To help me get my head around all of this I have done up a rough Excel spreadsheet (attached) that contains data from you, that attempts to arrive at (duplicate) your CU pole count. I've come pretty close, but I'm one pole greater than you in the Phase A. Could you please look at it and tell me where the discrepancy is? (I think it probably has to do with the kitchen(?))

As you will see, I have started with your spreadsheet, but have added some more things to help my understanding. This then has led me to some more questions:

Please see the attachment "DB layout".

2) The air conditioners are not explicitly shown on your spreadsheet. From our earlier discussions I interpret that these have been implicitly included within the "Socket Outlets", even though they will be hard-wired. Is this correct?

This is correct.

3) Whereas, the 3 shower water heaters are listed explicitly, and will also be hard-wired. Thus I am confused re why you have handled them differently on your spreadsheet.

The water heaters are a high power item & thus have a different affect on the MD result. It is also a requirement of ASNZ3000:2007.

4) In your spreadsheet discussion notes, to assure that I am absolutely clear, may I assume that when you say "RCD", that you mean MCB + RCD = RCBO? Whereas, [excluding the Main Switch], when you say "circuit breaker", that you mean only an MCB? (I'm sure that these are trivial questions; but I want to be absolutely sure that I myself know what I'm talking about, before beginning an 8 hour R/T trip to talk to a Thai salesman who has absolutely no idea what I am talking about.)

You will need an RCD/MCB aka RCCB aka RCBO.

FYI, tjo o tjim, thank you for your input -- I'm not ignoring it, I'm just trying to be sure that I understand elk's concept first...

I have also included a Clipsal RCD/RCCB info sheet to give you an idea about what you may need.

Here is the DB layout;

Here is the info about MCB's & RCD's etc;

I will delete this file in a couple of days.

Cheers,

Elk.

[zapatero]

1) To help me get my head around all of this I have done up a rough Excel spreadsheet (attached) that contains data from you, that attempts to arrive at (duplicate) your CU pole count. I've come pretty close, but I'm one pole greater than you in the Phase A. Could you please look at it and tell me where the discrepancy is? (I think it probably has to do with the kitchen(?))

As you will see, I have started with your spreadsheet, but have added some more things to help my understanding. This then has led me to some more questions:

Please see the attachment "DB layout".

2) The air conditioners are not explicitly shown on your spreadsheet. From our earlier discussions I interpret that these have been implicitly included within the "Socket Outlets", even though they will be hard-wired. Is this correct?

This is correct.

3) Whereas, the 3 shower water heaters are listed explicitly, and will also be hard-wired. Thus I am confused re why you have handled them differently on your spreadsheet.

The water heaters are a high power item & thus have a different affect on the MD result. It is also a requirement of ASNZ3000:2007.

4) In your spreadsheet discussion notes, to assure that I am absolutely clear, may I assume that when you say "RCD", that you mean MCB + RCD = RCBO? Whereas, [excluding the Main Switch], when you say "circuit breaker", that you mean only an MCB? (I'm sure that these are trivial questions; but I want to be absolutely sure that I myself know what I'm talking about, before beginning an 8 hour R/T trip to talk to a Thai salesman who has absolutely no idea what I am talking about.)

You will need an RCD/MCB aka RCCB aka RCBO.

FYI, tjo o tjim, thank you for your input -- I'm not ignoring it, I'm just trying to be sure that I understand elk's concept first...

I have also included a Clipsal RCD/RCCB info sheet to give you an idea about what you may need.

Here is the DB layout;

Here is the info about MCB's & RCD's etc;

I will delete this file in a couple of days.

Cheers,

Elk.

Thanks much, Elk!! I haven't studied everything yet, but I have downloaded the DB Layout. I am not sure whether the second download was successful though -- I got sent to [http://www.generatorsolutions.org/], but no indication where to find MCBs & RCDs, etc. Is that the link that you intended?

Thanks again,

~~z

[elkangorito]

Revised DB layout.

I forgot to include the downstairs lights in the first file.

A link to RCD/MCB info;

[http://updates.clipsal.com/ClipsalOnline/Files/Brochures/I0000013.pdf]

Remove the brackets, copy & paste the URL into your browser address bar.

Edited October 10, 2009 by elkangorito

[zapatero]

Revised DB layout.

I forgot to include the downstairs lights in the first file.

A link to RCD/MCB info;

[http://updates.clipsal.com/ClipsalOnline/Files/Brochures/I0000013.pdf]

Remove the brackets, copy & paste the URL into your browser address bar.

Thank you very much, Elk! What a great education I'm getting! But so much to learn, and so little time. I keep asking myself how did I ever get myself thrown into this position? Anyway, I don't want to overrun my welcome. Any time you get tired of this thread, please just say so and I'll keep quiet.

Until then, I have a couple of questions re your DB_Layout chart:

From your Maximum Demand load balancing chart, it appears that you have moved the 5A Outside Lighting demand from Phase B to C, and also the 12A "Load Group C" demand from Phase A to C. I probably don't understand something, but this appears to me to unbalance the three phases noticeably, toward Phase C. What am I missing?

On the notes from that same MD chart, you had an RCD on the Garage/(future outbuilding), but changed it to CB on the DB_Layout chart. Since that will also be my "workshop shed", don't you think it should probably remain an RCD?

I am curious what drives the placement order of the CBs and RCCBs on the/a DB panel layout? All that I have ever seen appear to be arbitrary/random. Is there any convention?

In your notes you say I "may be able to souce single pole RCCB's". Do you mean single pole in the electrical (switch) sense, or do you mean in the physical sense, (that it will only require one pole space in the DB)?

Finally, your Clipsal document looks very infomative, thank you -- but I really need to give it some time.

And really finally, I have located a Square D catalogue, (attached), if you or anyone is interested. Indeed, it does show some "Single Pole RCBOs", but I haven't had time to make sense of them yet...

Catalogue_Square_D_08.pdf

[elkangorito]

Hi Zap.

As usual, my comments in blue.

Thank you very much, Elk! What a great education I'm getting! But so much to learn, and so little time. I keep asking myself how did I ever get myself thrown into this position? Anyway, I don't want to overrun my welcome. Any time you get tired of this thread, please just say so and I'll keep quiet.

Until then, I have a couple of questions re your DB_Layout chart:

From your Maximum Demand load balancing chart, it appears that you have moved the 5A Outside Lighting demand from Phase B to C, and also the 12A "Load Group C" demand from Phase A to C. I probably don't understand something, but this appears to me to unbalance the three phases noticeably, toward Phase C. What am I missing?

On the notes from that same MD chart, you had an RCD on the Garage/(future outbuilding), but changed it to CB on the DB_Layout chart. Since that will also be my "workshop shed", don't you think it should probably remain an RCD?

Sorry about the errors. Hopefully, I've fixed them all. See the attachment "DB layout rev 3".

I am curious what drives the placement order of the CBs and RCCBs on the/a DB panel layout? All that I have ever seen appear to be arbitrary/random. Is there any convention?

There isn't a convention. Just use best fit for phase allocation.

In your notes you say I "may be able to souce single pole RCCB's". Do you mean single pole in the electrical (switch) sense, or do you mean in the physical sense, (that it will only require one pole space in the DB)?

Sorry. I meant a single pole space (18mm).

Finally, your Clipsal document looks very infomative, thank you -- but I really need to give it some time.

And really finally, I have located a Square D catalogue, (attached), if you or anyone is interested. Indeed, it does show some "Single Pole RCBOs", but I haven't had time to make sense of them yet...

I can't download the Square D catalog due to download errors. Seems to be happening a lot lately. Can you please supply the URL for the catalog.

[zapatero]

And really finally, I have located a Square D catalogue, (attached), if you or anyone is interested.

I can't download the Square D catalog due to download errors. Seems to be happening a lot lately. Can you please supply the URL for the catalog.

Elk: I have looked for it. Unfortunately the Schneider folks, (at [email protected]) sent me the catalogue, without a link.

If you or anyone is able to download it, I would appreciate any experience or comments regarding:

1) The "VisiSmart" vs. "Classic" enclosures -- what is the difference, and does it matter?, and

2) The "Single Pole RCBOs" listed on page 6. Any opinions as to whether any of these might be appropriate for Elk's concept solution for my problem?

If anyone wants me to try to resend my Square D catalogue attachment, please tell me.

[elkangorito]

Elk: I have looked for it. Unfortunately the Schneider folks, (at [email protected]) sent me the catalogue, without a link.

If you or anyone is able to download it, I would appreciate any experience or comments regarding:

1) The "VisiSmart" vs. "Classic" enclosures -- what is the difference, and does it matter?, and

2) The "Single Pole RCBOs" listed on page 6. Any opinions as to whether any of these might be appropriate for Elk's concept solution for my problem?

If anyone wants me to try to resend my Square D catalogue attachment, please tell me.

I just tried to download it again. I got this message, "The file is damaged and cannot be repaired." This message is from Adobe Acrobat.

This is very strange because I have no trouble downloading larger pdf's from the web. I think it is a TV problem.

In the meantime, I will send you a PM about how to get the Square D catalog to me.

Also in the meantime, I have some questions re your electrical job, as follows;

1] What has been completed?

2] What is your "plan of attack"?

Also, make sure you find out the "list price" for items that you may want to purchase. Your electrical wholesaler MUST NOT exceed the list price. There will be legal reasons for this.

[elkangorito]

PM sent.

Please let me know when you have sent it to me.

Edited October 11, 2009 by elkangorito

[zapatero]

PM sent.

Please let me know when you have sent it to me.

Elk: It's on the way. Also, I will attach it again to this post, in case others are also having problems.

Re your questions:

What has been completed?: Most of the wires (3-wire convention) have been strung on the first floor, none on the second. My ET says we are still O.K. without the panel and distribution design yet, but will need it pretty soon.

What is my plan of attack?: Regrettably, uncharacteristically of me, I don't have one. As I've indicated in my earlier posts, I never contemplated being in this position. My builder said his electrician was an "expert" so I (naievely) accepted that and presumed that he could put this thing together if I just gave him the requirements. Having only lately concluded otherwise, I have tried every avenue that I can think of to obtain some professional design guidance, but there is none (that I am aware of) in my town. (Including the PEA.) And I don't know where else to look. So absent any such guidance, I concluded that I myself would have to accept this role as designer, and that is when I began tapping you and the other kind folks in this forum. So my "plan of attack", if you can call it that, is to try to learn what must be done, so that I can tell my ET what must be done...

I think I'm keeping barely ahead of the alligators, but if I have to hold up the construction, I will do that...

Catalogue_Square_D_08.pdf

[elkangorito]

Ok Zap. I have received the catalog. Give me some minutes to look it over. Please wait.

[elkangorito]

I'm not sure about the RCCB's. Do they take up 1 pole space or 2 pole spaces? This info is not clear in the catalog. Contact Square D about this. If they take up 1 pole space, you would need the QO1xxvs6RCBO30. The xx is the curent rating.

With regard to the Distribution Board (DB), the QO3-100L36G/SN looks ok. But it doesn't seem to have a Main Switch. You need to verify this with Square D. If it doesn't have a Main Switch, no problem. It's easy to remedy. I can update my DB layout to show a Main Switch.

I still think you need a 36 pole DB, even if you do ultimately use single pole RCCB's (1 pole space). Also, the DB will need 2 neutral bars...1 for unprotected neutrals & 1 for RCCB protected neutrals. Ask these questions to Square D.

Further, what about your earth stake? Do you have an MEN system in your area? Will the sparky conduct "tests" upon completion & before "power up"?

EDIT: You can use the 36 pole DB (the one without a Main Switch) ONLY if the RCCB's are 1 pole space. If the RCCB's are 2 pole spaces, you will need a bigger DB.

Edited October 11, 2009 by elkangorito

[elkangorito]

One more question...what size are your present supply cables? Are they aluminium or copper?

I advise against aluminium cables for your new installation. Try to ensure that you have 50 amps per phase availability for your new installation.

[zapatero]

I have found out a few things from Schneider/Square D that might be helpful to other people:

What's the difference between a Consumer Unit and Load Center? Ans: CU is single phase, LC is 3 phase

What's the difference between the "Visi Smart" and "Classic" designs? Ans: Mostly the paint! But the VS models have a curved front plate. He says most people still use the Classic

What's the difference between a "Main Breaker" and "Lug" model panel? Ans: The Lug model goes direct, without passing thru a main breaker

To answer some of your questions, Elk:

The QO1xxvs6RCBO30 series RCBOs do occupy only one pole slot in the distribution panel, (not two)

Based upon what I have just learned (above), your suggested QO3-100L36G/SN panel is a "Main Lug" type Load Center.

I think now that their comparable QO3-100EZ36G/SN "Main Breaker" type Load Center might be appropriate -- what do you think?

BTW, "EZ" refers to their EasyPact main breaker series; whereas, (I presume), "L" indicates Lug.

I am not clear yet on split Neutral bars -- I've asked for more details

I am O.K. on the earth stake now. Yes, indeed there is definitely a MEN system in our area. Even the PEA guy affirmed this (for which I give him some credit) and showed me his diagram. My ET, (sparky) has assured me that he intends to do full testing before power up. (Of course the word "full" is open to examination). But he is pretty conscientious, so I expect that he will do this as comprehensively as he knows how, (considering the TiT factor limitations.)

Regarding our present supply cables, we have none yet, so this is still an open issue. We do intend to run underground from the utility pole though, so I presume, from your and Crossy's webdoc, that these cables will need to be derated.

Finally, a question, a comment, and more information:

Question: Has anyone attempted to extend the two diagrams in the "Distribution Board/Consumer Unit" section of the Crossy webdoc -- from single phase to three phase?

If so, that would surely help me to get my head around this thing that we are creating.

Comment: Some may find it amusing, (as I do ), that the Safe-T-Cut sales reps have visited our site three times now, trying to convince my ET and me that their product is the way we should go...

More Information: I have just received more pages from the Square D catalogue, which I will attach to this post. These pages address MCBs, RCBOs, and SPDs; with more specifications and pictures.

Elk, the RCBO series that we have been discussing is shown. Note the cables coming out of the bottom, which he says are the "inputs".

Catalogue_Square_D_08_page11_20_.pdf