Does anyone know the Amperage rating on Schneider Conext XW PDP DC positive Busbar?

blacknbart

Just trying to understand how much amperage could potentially be going thru the DC Positive busbar inside the PDP.  Thought it was just 100 amps then 200 amps, but I had one person say we may see 400 amps.  We're looking at the XW Pro Inverters with the Closed-loop Xanbus communication so we can have some coordination with the equipment and batteries not overcharging.  Just curious about what kind of amperage I may see at the busbar.  The Schneider manuals don't mention any kind of rating, but I imagine it rated high.  Thanks for the review I have three attachments with line details of my project. 

SomeJ

Gonna bump this as I too am curious.  I have an inspection coming up and have a feeling this may get asked as I have quite a bit of stuff plugged into that dc buss bar.  Much googling and reading every possible document Schneider has posted on the solar website has yielded zero info as to the actual amp rating of any buss bar. (In my case Im looking for info on the 2 inverter buss bar and the 3 inverter buss bar)

J

Dave Angelini

It is on the Schneider website! You are searching the wrong things if you are not finding it.

SomeJ

Using the product page and documents here: https://solar.schneider-electric.com/product/xw-power-distribution-panel/

I've looked through the data sheet and all of the English user documents.  Some make reference to the DC pos bus bar, but there is no amp specs for ether bus bar.  The documents that do show the pos bus bar have no part numbers for that specific item (to then search against).

The INV2_INV3 kit (865-1020-02) specifically calls out the inclusion of the 3 position DC pos bus bar, but has no part number or info for that bus bar.

I've also looked through the wiring documents on the XW+ product page, they show the DC pos bus bar for the PDP, but do not list any amp specs for the bus bar.

If you have any other hints for finding this data then please do tell, it is clearly no where to be found on Schneider's product page for the PDPs or the documents that page links to.

J

MichaelK

The main DC breaker for the XW+ is 250A, so should you assume the bussbar is the same?

Dave Angelini

If you are buying the equipment from the store here, they can help you. I often use them and they refer to me at times.

Adam Douglass B.S.E.E.
Solar Applications Engineer, Northern Arizona Wind & Sun

(928) 526-8017 ext.108 | (800) 383-0195 ext.108

As general info, it is on the Schneider website and you can ask them.

 https://solar.schneider-electric.com/netsuite/

Specific info I do not answer on the forum. I do this for 3 reasons.

I could be sued. I live up in the mountains of California and they can find me.

It is not fair to my clients or my power system Pros that I work with. I spent 30+ years doing this on 300+ systems.

The last thing, I am a capitalist. I do not charge that much to get a code compliant power system that will stand the test of time. It will save you time and headaches. It is guaranteed also.

https://solar.schneider-electric.com/installer/dave-angelini-offgrid-solar/

SomeJ

Ticket with Schneider requesting the information has been submitted.  I will happily post here whatever info they provide so others who are needing it has "easy" access to it.

While the PDP does come with one 250amp breaker, there is a spot for a 2nd breaker along with other power connections, then the bus bar that comes with the 865-1020-02 kit has spots for 3 inverter breakers.  Code for a bus bar says it must handle the sum of all over current devices connected to it +25% (on the "line" side I assume).  Using the expansion kit bus bar, that has three inverter spots on it, spots for four charge controllers and two spots for additional high amperage "devices" or batteries. Just doing the math for three Schneider XW+ inverts and four Schneider MPPT 60 charge controllers would give you 1,437.5 amps based on the breakers connected to it (excluding the battery breakers in this math, but that could potentially drive the number up even more). ((250+250+250+80+80+80+80+80)*1.25)  This size of a setup has been drawn up as a solution on Schneider's own site.  That's quite a bit of amps, I can see why the state/local inspector might want to see this manufacturer info.  In reality would that bus bar ever see anything close to that... Never, not even close.  The DC output of the inverters is much lower than the input, and the breakers are rated for the max DC input, but... Code says... So might as well CYA when asked.  A good inspector probably will never question such a setup unless they are having a really bad day or someone is pushing them to do so.  In my case the state is calling it out on the permit documents.

Midnight Solar provides this info in the documents for their combiner/PDP equipment, there is no reason Schneider or anyone affiliated with them should be so tight lipped about it.  No trade secrets would be revealed by providing such info or even better, links to documents with that info.  Providing manufacturer documentations would actually protect you from any potential suit if that really was your fear.  But then again, if you really had any legit legal fear you would not be here providing as much help as you do.  So logically the issue would then sound more on the capitalist side.  While I do get it, everyone needs $$ to survive, but these forums are here to help provide info to the general public at no cost (or is there a fee for these forums that I missed somewhere?).  I would totally understand requesting some kind of compensation for design help, but compensation for documentation that should already be accessible to the general public just doesn't sit well with me.  If you have read this full reply, you have already spent more time reading than it would have taken to just post any manufacturer info.

I respect everyone who is in a trade industry.  Many of them do things that others can not, or will not do, and they help keep society functional and safe.  Asking for payment for manufacture documents on a free information forum is pushing the limits in my book though.

J

Dave Angelini

The store here needs to stay in business for this to be free BTW.

SomeJ

And I have purchased many products from them and will continue to do so.  They have an excellent website, great customer service (the few times I've "needed" it), awesome prices, and of course these forums for help and info is a nice addition.

Dave Angelini

Cool !   If you had said that I probably would have been more help off of the forum. I support them also! When I see someone with 7 posts here I clam up. I do not know your background or experience.
  You may not believe it but I have buds who have been sued in this business from something that was said on a forum. Not fake news either. I have not been sued and do not intend to be. All of those warnings in an XW or Radian manual are to keep the Lawyers away.

Good Luck!

blacknbart

Looking at my energy layout and the equipment specifications we determined that there could be a potentially the max 200 to 400 or maybe more Amps flowing through those DC Bus bars.  We also are assuming maybe those bus bars are rated for 1000 amps or more. I have poured over all the equipment manuals for this information to no avail.  I wonder if the information is stamped into the Bus bar itself or if it’s is label within the confines of the equipment literature. Regardless, I’m very curious to find out as well I’m not looking for my cities inspector to start asking questions that I don’t have the answers for I’m definitely looking to passcode 100%. I’m looking to fill out my PV plan as close to 100% I can so I can minimize the resubmittal process.  I’ll have to research more on this subject and report back with my findings.  Thanks for the input fellas and please report if you find anything new. 

BB.

Some calculations you can make:

https://www.electrical4u.net/electrical/what-is-busbar-current-carrying-capacity-calculation-5-types-of-busbar/#:~:text=Which means, take a copper,sqmm* 1.2 =1200 Amps.&text=Hence the total current carrying,width and 10 mm thickness.

https://www.copper.org/applications/electrical/busbar/busbar_ampacities.html

https://www.copper.org/applications/electrical/busbar/bus_table3.html

-Bill

mcgivor

The electrical code is limited in scope to the electrical  distribution, appliances or equipment connected thereafter are subject to certification by independent governing bodies such as ULC or CSA etcetera  in North America.

Equipment which has passed the requiments may be connected without sanction from electrical inspectors because they don't have durisdiction, they can however request certification be provided if none is attached

Schneider has a 250A maximum DC circuit breaker for a reason, it's to protect the internal circuits of the inverter  from overcurrent, they have no obligation to provide this information to the public, but rather to the governing bodies providing certification. The maximum allowable current within the configuration of multiple devices allowable by the manufacturer has to has comply with  certification requirements, not with an inspector.

Having dealt with electrical  inspectors  on many installations  of non conformity, the only requirement is to have it certified, by it ULC, CSA or one of their represintive sub contractors.

blacknbart

@mcgivor We were assuming those breakers would pop if the current was exceeding that amperage.  Just wondering what could be the highest Amperage that would flow-thru those Busbars.  I'm firm on the 200+/- Amps as being the most they'll see, but I had a battery technician mention that we could see 400 amps. I'm not sure if they understood the Schneider equipment, but it made us wonder and look into the real numbers.  Using the closed-loop system should balance out that possible higher amperages from happening.  Just curious about that Mysterious Busbar rating. Thanks for the input. (Check recent posts for my Attached Electrical current diagrams)

mcgivor

You could measure the thickness and width in millimeters, for example 10mm by 50mm would have a cross sectional area of 500mm^2, multiply by a factor of 1.2A per mm^2 for copper or 0.9 per mm^2 for aluminum, so 600Ah or 400Ah respectively. This is a basic formula, factors which may vary the actual current will include length, wether in free air or still air and ambient operating temperature, more complex formulas may state 2A per mm^2 then derate according to application.

 

blacknbart

Thank Mcgivor sounds like a great solution, but I don't have the equipment yet.  I will take your into consideration.

Saggys

Assuming you will be in some type of a gutter or enclosure article 366.23 in the 2020 NEC states continued current in bare copper bars shall not exceed 1000 amps/ inch2 of cross section of the conductor. Good luck on your inspection.

mike760

Breakers have more to do with the connected conductor size than the inverter.  The stock cables are 4/0 which are generally good for 260A therefore the 250A breaker size in the PDP.  In the mid/late morning I will start to see the charge controllers hitting a combined 20,000W.  At that point my demand is usually around 10KW and the batteries are taking in about 10KW as well.  That means there is over 400A on that bus bar.  I recently measured about 330A on my battery cable which prompted me to add a parallel set since I noticed wire temps hitting 175F.