# panel AIC rating?



## l0sts0ul

Question, 

Just received a quote from a wholesaler, and they list the 400A 347v/600v 30cct panel as 10k AIC Fully Rated. Note this panel is main lug.

This is a "sub panel" after the main disconnect on a 300A main service that is being changed from 208v to 600v.

How can the manufacturer rate a panel at 10k AIC? (assuming i am right in thinking they mean available interrupting current) then do they mean that is the largest AIC rated breaker I Can use? 

I know that I have 2, 600v 53 amp compressors I have to hook up to this and they actually list the short cct current on the compressor as 25KA RMS sym.

so my assumption would be I would have to hook up these compressors with either fused disconnects with a min rating of 25KA IC rating, and feed those with a 10KA rated breaker, or run 25KA breaker, with an unfused disconnect.

either way, I Guess this has turned into a 2 prong question, lets go over this again lol.

1.) does this panel not have the allowances for 25KA breakers (and can a buss even be rated at only 10KA?)

2.) if the buss is only rated at 10KA, I obviously can only use 10KA rated breakers, but if the fuse between the 10KA breaker, and the unit requiring 25KA rating, would this not meet the code?

also, maybe this shoudl have been posted in the CEC section... sorry for my wall of text,..

lol
:jester:


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## Pharon

Only OCPDs have AIC ratings. Panels have withstand (SCCR) ratings.

If the panel's withstand rating is only 10k, then you can't put more than 10kAIC breakers in it.


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## l0sts0ul

ok, I understand.

Now that I look at it the quote states "S.C Rating: 10K A.I.C Fully Rated"

so im assuming that is just a manufacturers short notes for SCCR rating. Therefore the 10KA rated breakers are max. 

Now to my second part of the question. I should be able to run proper fusing at 25KA rating to meet requirements for OC protection on this cct at a fused disconnect between the 10KA rated breaker and the compressor, right?

thanks


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## Pharon

I'm pretty sure that as long as your withstand rating is higher than your AIC ratings, you should be fine.


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## Ultrafault

What is the available fault current of the system at the lugs of your 10k s.c. Panel. If it is more than 10 k you need a different panel.


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## l0sts0ul

I don't know what the available fault current is at the panel...

Id have to calculate it... I haven't done an AIC calc since school for a panel install... suggestions?

this would be a "sub panel" after the main disconnect fed directly from the poco.


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## Pharon

What's the POCO transformer size in kVA?


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## l0sts0ul

300 kva. 15kv to 347/600. Would the math look like this?

300000 / ((600x1.732)x.05 (approx %iz of poco xfmr))

so roughly 5774.78 sym amp?

thanks


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## Ultrafault

Your not quite there.
You need to know the impedance of the transformer and the length and size of the conductors feeding your panel.


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## Ultrafault

Around here there is no way the poco would put in a new 5% it would be a 2%


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## l0sts0ul

OK, I have a call coming back from the poco on the %iz, but as far as length I can only guess and size for now, until the poco shuts down and I can open the main. In the mean time, I need to quote this. being the existing conductors are running from a 112.5kva 208v transformer they have 300Amp coming it. using our tables that would be a 300mcm (320 amp) and again, the %iz is not listed, so I dont know it.

I just need to get a number I Can use to quote with whether it has to be 10ka or 25 ka or what lol.

thanks guys.


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## l0sts0ul

also, the rough length of conductors from the secondary of the transformer to the main disconnect is 40m (130ft)


I know it school when we were taught voltage drop, we had to use a formula stating that the max voltage drop from the poco tranny to the device (15a plug) could not exceed 5% (thats our code) and generally we would state that 3% is the max voltage drop along any conductors to a device.

by this logic, I could assume a 2%IZ for the conductors to the main disconnect would be safe. I think. 

Would I then change it to this:

300000 / (10398.02) = 14436.959amp sym?

thanks again


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## Dennis Alwon

Has anyone engineered this job. Are you sure the 10k aic rating is correct. You do not want to have an issue if that panel needs to be higher than 10K


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## l0sts0ul

There is no engineer on the customers side of the job. the poco has done their work, and they have chosen they want to reuse the secondaries on the transformer going back into the building. 

poco does not require engineers on the customers side of the secondaries.

I am not sure about the AIC rating, hence the reason why I am here, trying to decide what my AIC rating has to be in order to supply the quote with the right panel to accomodate what we may need.


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## Dennis Alwon

You have to know what the transformer aic rating in then you need to do a calculation. I would insist on an engineer doing this. MIKE HOLT has a free online aic calc or fault current calculator http://www.mikeholt.com/technical-calculations-formulas.php


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## wildleg

maybe you should consider getting a quote from an engineer to design the system (he would then be liable), and quote the customer the charges (plus yours) prior to quoting the (correct) equipment.


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## hardworkingstiff

l0sts0ul said:


> I know that I have 2, 600v 53 amp compressors I have to hook up to this and they actually list the short cct current on the compressor as 25KA RMS sym.
> 
> so my assumption would be I would have to hook up these compressors with either fused disconnects with a min rating of 25KA IC rating,


If the PoCo and distribution system limits the AIC to 10K, then how does the short circuit rating of the compressors increase the AIC requirements?

I've never heard this question before (but I'm not that well educated).


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## Pharon

The only real missing piece here is the POCO transformer impedance. Once you have that, you can figure out if 10kAIC is good enough for your subpanel OCPDs.


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## Pharon

hardworkingstiff said:


> If the PoCo and distribution system limits the AIC to 10K, then how does the short circuit rating of the compressors increase the AIC requirements?
> 
> I've never heard this question before (but I'm not that well educated).


It doesn't. the SCCR of the compressors just tell you that you could put them on a system up to that limit - it's just a withstand rating (like panel bussing). They don't increase the AIC requirements of the OCPDs.


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## Dennis Alwon

I suspect the power company has more than a 10k trany but it is possible , depending on distance, materials etc, that a 10k panel can be used near the end of the runs. Look at the formula to see all the variables


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## l0sts0ul

pharon, being my main disconnect is going to be fused, and most fuses are rated at 100krms, this should be fine right?

also, getting an engineer involved would be nice, however the extra 2-2500 bucks the customer cannot afford, and if I can do the calculation, why would I not? liability aside, I realize I am taking responsibility to a point, but even with an engineer doing to design work (which is picking a panel SC rating, and breaker AIC ratings for branch ccts) I still carry 85% of the liability anyways because I am doing the install, engineering firms carry little to no liability up here. even IF they do design, blatant negligence is the only way they would be even remotely at fault.


anyways, if the %iz of teh transformer is 2% or more, would my previous calculation be correct pharon?

thanks


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## Ultrafault

A 2% 300kva 600 volt would give you 14450 afc at you transformer terminals. If you assume an infinite buss from the poco. I cannot determime the impedance of your conductors untill I am home.


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## Pharon

l0sts0ul said:


> pharon, being my main disconnect is going to be fused, and most fuses are rated at 100krms, this should be fine right?


It depends on the let through value. That's where fault current curves come in handy. Your assumption is probably right, but there is still uncertainty.



l0sts0ul said:


> anyways, if the %iz of teh transformer is 2% or more, would my previous calculation be correct pharon?


Yes, your calculations look right to me. If the transformer impedance is between 5.75% and 2%, then the maximum fault current you would see, not even taking into account the impedance of the conductors, is in the range of 5k to 14k amps. The problem is that 10kAIC falls right in the middle of that range, so you need more info to come to a conclusion.


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## l0sts0ul

the whole idea is that the AIC rating of the breakers, and the SC rating of the panel has to exceed whatever the max AIC available to branch cct breakers betweenn the 400a main disconnect and the branch cct breakers


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## Pharon

Correct. :thumbsup:


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## l0sts0ul

now, here is the next question lol, 

If my main fuses are rated 100k rms, would that not be high enough to protect the entire cct between the "sub panels" and the poco tranny? so having said that, assuming all devices and breakers in the branch ccts of the sub panels, dont require anything bigger than 10KA, the panel could be rated at 10ka?


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## Pharon

Not necessarily. 100kAIC fuses will withstand and clear a fault up to 100kAIC, but that doesn't mean that it happens instantaneously. There is a time before the fuse clears the fault that there is a certain amount of let through current that will flow. And if that amount is over 10kA, then your 10kAIC breakers will be undersized. You can find out how much it is if you have a time-current curve for that type of fuse.

Make sense?


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## l0sts0ul

yes. makes sense. 

now would choosing, and time delay fuse over a quick blow fuse be the simplest solution to that question, or would looking at the graphs be the only way to tell, and what current over time requirement would I be looking for? the earliest point where the fuse would trip over 10KA?


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## Pharon

The time current curves (graphs) are the only way to tell. And you would want to check to see that the fuse blows at its lowest rating (usually 0.01 sec) less than 10kA.


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## l0sts0ul

lower than 10ka? where can I find the graphs usually?


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## Pharon

If you know the fuse type and manufacturer, you can do a google search for it online.


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## l0sts0ul

well now...

it seems that, had the poco called me back a little sooner, they could have pointed me to the section of the connection guide that they put out that lists "interrupting capacity for main switchs or breaker size, all the way from 120/240v 1phase to 347/600 3phase. LOL

for 201-600A at 347/600v 3phase 4 wire, they require 22000.

HAHAHA, damnit, all this for nothing more than a little education.

thanks all very much, but it seems the documentation basically has proven we are all right. (and by the way, we are told to assume a 2%IZ on all POCO xformers)





still though, I want to understand something. on the breakers feeding these compressors I need a panel rated no less that 25ka rating, but lets say down the road they have another transformer, feeding another sub panel. if I Wanted to calculate what size SC rating, and KA rating I would need for breakers in that (for ease sake) 120/208v sub panel, how would I run that calculation.

basically now I would have lets say a 50A 208v compressor that is 100' away from the panel. it is fed from a 100A 3p 208v breaker. What does the rating of that breaker have to be? and what woudl the rating of the breaker feeding teh step down transformer (lets say 150v kva 600-120/208v) feeding a 400a subpanel that is fed from the 400A 25ka panel (25ka rated breakers) fed from the main disconnect?


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## Pharon

l0sts0ul said:


> still though, I want to understand something. on the breakers feeding these compressors I need a panel rated no less that 25ka rating


Based on what POCO just told you, it wouldn't have to be higher than 22kA.



l0sts0ul said:


> but lets say down the road they have another transformer, feeding another sub panel. if I Wanted to calculate what size SC rating, and KA rating I would need for breakers in that (for ease sake) 120/208v sub panel, how would I run that calculation.


The maximum fault current you would ever get downstream is based on that new transformer kVA size and impedance.



l0sts0ul said:


> basically now I would have lets say a 50A 208v compressor that is 100' away from the panel. it is fed from a 100A 3p 208v breaker. What does the rating of that breaker have to be?


To be safe, make it 22kAIC, to match your service rating.



l0sts0ul said:


> and what woudl the rating of the breaker feeding teh step down transformer (lets say 150v kva 600-120/208v) feeding a 400a subpanel that is fed from the 400A 25ka panel (25ka rated breakers) fed from the main disconnect?


The primary breaker would be 22kAIC, and the secondary breakers would be 10kAIC if that 150kVA transformer has a 5.75% impedance (7,241A available fault current).

Keep in mind, all these values are worst case -- and can be reduced if you factor in feeder size/lengths.


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## l0sts0ul

Pharon, thanks for all your help. we go through all these calcs in school, but so few times do I have to use them, that we lose practice. The theory is all still there, just rusty. 

appreciate it, sincerely.


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## don_resqcapt19

Pharon said:


> Not necessarily. 100kAIC fuses will withstand and clear a fault up to 100kAIC, but that doesn't mean that it happens instantaneously. There is a time before the fuse clears the fault that there is a certain amount of let through current that will flow. And if that amount is over 10kA, then your 10kAIC breakers will be undersized. You can find out how much it is if you have a time-current curve for that type of fuse.
> 
> Make sense?


You can't use the curves to find out if the fuse can protect the downstream overcurrent protective devices. You can only use fuses that are part of a tested and listed "series combination" to do that. See 240.86(B).


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## l0sts0ul

Deleted


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## Big John

That's the series-rating of the equipment. I don't know how to do that calculation, but the idea is that you're adding in the circuit impedance from your 22kA panel and seeing if it will effectively ballast your downstream current flow to the point where you can safely get away with 10kA AIC protection.


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## Pete m.

Current limiting fuses will not automatically provide protection for MCCB's even if the let-through charts show a value below the MCCB's AIC rating.

The only way to know for sure is to employ a listed and tested combination.

Several years ago we had an IAEI meeting where I invited a engineer from Bussman and one from Square D. I asked a very pointed question about current limiting fuses protecting downstream MCCB's. Both of the engineers said that there is no mathematical way to prove that the higher AIC fuse will protect the lower rated MCCB without actual testing.

Pete


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## zen

Would j type fuses ahead of service equipment help

no matter what we theorize as electrics. It has always been .


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## JRaef

l0sts0ul said:


> ok, I understand.
> 
> Now that I look at it the quote states "S.C Rating: 10K A.I.C Fully Rated"


Whomever put that on a quote is a nincompoop. "AIC" is an acronym for "Amps *Interrupting *Capacity". The reason it is a term that can ONLY be applied to a breaker or fuse, is because the device having that rating has to _*INTERRUPT *_something. How can a main lug only panel interrupt anything? By melting down perhaps? I don't think that could apply...



> so im assuming that is just a manufacturers short notes for SCCR rating. Therefore the 10KA rated breakers are max.


 Nope, SCCR means Short Circuit Current Rating, formerly called a "Withstand" rating. That means this is the amount of short circuit current that the device, such as bus bars mounted and braced in an enclosure, can handle without sending shrapnel and blobs of molten copper off into the local environment. Most likely I think you have come across a supplier who has no idea what you are asking him for, so he is just grabbing numbers and throwing them out there hoping to make you stop bothering him. Might be time to move on.



> Now to my second part of the question. I should be able to run proper fusing at 25KA rating to meet requirements for OC protection on this cct at a fused disconnect between the 10KA rated breaker and the compressor, right?
> 
> thanks


Not sure what you are saying there. In general though, using fuses to lower the available fault current ahead of a piece of equipment rated lower than what is available at the terminals is not something that you can just pull out of your butt, it takes some careful engineering. The AIC rating of the fuses has little or nothing to do with it, it is the LET THROUGH current of a current limiting fuse design, the amps that get past the fuse under fault conditions, that matters. So a fuse that is not current limiting, but rated 25kAIC, would be meaningless as far as the down stream equipment protection.


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## Ultrafault

Pete m. said:


> Current limiting fuses will not automatically provide protection for MCCB's even if the let-through charts show a value below the MCCB's AIC rating.
> 
> The only way to know for sure is to employ a listed and tested combination.
> 
> Several years ago we had an IAEI meeting where I invited a engineer from Bussman and one from Square D. I asked a very pointed question about current limiting fuses protecting downstream MCCB's. Both of the engineers said that there is no mathematical way to prove that the higher AIC fuse will protect the lower rated MCCB without actual testing.
> 
> Pete


Of course there are ways to mathmaticaly model the power under fault conditions. Just no way to do it legaly without testing.






Sent from my PC36100 using Tapatalk 2


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## l0sts0ul

JRaef said:


> Not sure what you are saying there. In general though, using fuses to lower the available fault current ahead of a piece of equipment rated lower than what is available at the terminals is not something that you can just pull out of your butt, it takes some careful engineering. The AIC rating of the fuses has little or nothing to do with it, it is the LET THROUGH current of a current limiting fuse design, the amps that get past the fuse under fault conditions, that matters. So a fuse that is not current limiting, but rated 25kAIC, would be meaningless as far as the down stream equipment protection.


im confused at this point, but this is what I guess Im trying to get at, lets see if we can straighten this out. 

There are 2 compressors, 52amp 600v each. They list on the nameplate that they have a SCC of 25kA RMS Sym, 600vac max. they require an AJT fuse at 70A max. after looking at this again, the ajt fuses are rated at 200KA AI rating. That would be the branch cct fusing for each compressor. 

now, I have to feed a splitter that is existing with 2 fused disconnects with these fuses in them (im assuming as there is a lot of work that has to go on before I can get to this point but I'm quoting to plan ahead) so based on our code rules in the CEC, conductors are based on the first motor x 1.25 + fla of second motor. 

branch cct OC device FLA of the first motor x 250% (for breaker) + FLA of second motor (but shall not exceed this value) 

Based on this the OC device could be as high as 182AMP but we know that doesn't exist, so 175 would be MAX, and conductors would be 111Amp minimum rated. 

back to where I Was going before I digress further. The fused at the service disconnects on each machine will be set at 70A, 200KA AIC rated fuses. The breaker that is feeding this splitter has to be either a.) 10ka or b.) 25ka rated? 

im thinking 25KA SCC on the compressors dictate that size. 

comments?

thanks


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## Big John

I think we're making this more complicated than it needs to be.

Your service or feeder will have an available fault current. 
Panels and equipment will have a short-circuit current rating. (e.g. 25kA SCCR)
Overcurrent protection will have an amperes-interrupting capacity. (e.g. 10kAIC)
Overcurrent protection will also have operating rating (e.g. 150A slow-blow)

1) Determine the available fault current.
2) Select panels that have an SCCR as high or higher than that AFC.
3) Select beakers/fuses that have an AIC as high or higher than that AFC.
4) Then size those breakers of fuses per the NEC to determine the correct operating rating.

That said, I agree with others that determining series-ratings of OCP is not something you can guess at if you don't want to use 22kAIC for everything. As Pete and Jraef both mentioned, manufacturers publish listed series-rating combinations, and this needs to be engineered.


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## 99cents

This is great information. I don't know if anyone can answer this but are tested series combinations a requirement in Canada (the OP is Canadian)? 

In general, I know at one time there was a loophole for "umbrella" fuses but I assume that loophole has been closed by now.


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## zen

Thats what I say big john. . J type fuses at the first disconnect

no matter what we theorize as electrics. It has always been .


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## l0sts0ul

I guess the reason this is more difficulties because I am not doing a fresh install I am changing a service from 300a 208 to 300a 600v all because of these compressors. 

Poco requires at least 22ka rated service disconnect. 

Basically everything downstream of this disconnect is rated all over the place from step up tranaformers that I now have to reverse, equipment that was rated at 208v is now having to be rewired for 600v and to make it more fun, I have little to no space for this equipment. 

Using an engineer for this is a waste of money as really there is no engineering to be done (thati can see.) I'm trying to understand the OCP Ratings required for the devices downstream of the main disconnect we have to install.


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## zen

Id say your doing a good job at solving the problem. Hell the only resson I have a clue and I dont is because I was with a jman waiting on a service inspection. Jman is younger than I. Inspector showed up and went crazy on him about the afc, samething as u 10k at the panel. Told him he was sick of people not knowing this stuff. .then he explained to me how to correct and said always start with first fuse

no matter what we theorize as electrics. It has always been .


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## Ultrafault

l0sts0ul said:


> I guess the reason this is more difficulties because I am not doing a fresh install I am changing a service from 300a 208 to 300a 600v all because of these compressors.
> 
> Poco requires at least 22ka rated service disconnect.
> 
> Basically everything downstream of this disconnect is rated all over the place from step up tranaformers that I now have to reverse, equipment that was rated at 208v is now having to be rewired for 600v and to make it more fun, I have little to no space for this equipment.
> 
> Using an engineer for this is a waste of money as really there is no engineering to be done (thati can see.) I'm trying to understand the OCP Ratings required for the devices downstream of the main disconnect we have to install.


It sounds like there is alot of engineering to be done, as you just explained. If this were the US you would need an arc fault study as well. 
Spend the customers money to provide a saftey net for yourself and anyone else who comes into contact with this install.

Sent from my PC36100 using Tapatalk 2


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## Pharon

l0sts0ul said:


> Using an engineer for this is a waste of money as really there is no engineering to be done (thati can see.) I'm trying to understand the OCP Ratings required for the devices downstream of the main disconnect we have to install.


POCO told you available fault current at the service is 22kA. Why not just make things simple and size everything downstream to be 22kA? Unless you feed another transformer - then do a calc.


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## Big John

Understood, but it sounds to me like you're mixing ratings. 

What the NEC requires you to calculate to protect your circuit conductors is unrelated to what you need to calculate in order to select the AIC ratings on the fuses/breakers. They're two separate steps.

If you don't want to have a coordination study done, then I see two options: 
A) Make sure everything has the same ratings as the service disconnect. 
B) Figure out how to use one of the listed series-rated combinations from a breaker Eaton, Square D, Cooper, whoever and install those.

This may help explain series rated equipment.


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## l0sts0ul

I do have to feed another 150kva 600-120/208 step down to re feed all their leftover lights equipment etc. Literally all I'm changing is main disconnect and cts/pts for the service. And fe feedin a few existing things. 

This is why I'm discussing the use of an engineer. The cost will be much greater and up here, engineer are used very infrequently for stuff like this because of the overhead cost and lack of actual input. A lot of engineering firms (most) don't even want to look at this because it's not required by their views and it takes so long to get anything done.


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## don_resqcapt19

240.86(C) may be an issue with a series rated system if the lower rated breakers are 10kaic.


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## l0sts0ul

I can appreciate you quoting rule numbers from the NEC. But being they are something I can't look up, it's useless to me to understand u less you actually quote the rule.


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## Dennis Alwon

don_resqcapt19 said:


> 240.86(C) may be an issue with a series rated system if the lower rated breakers are 10kaic.


He is Canadian so the rule may be worthless.



> 240.86(C) Motor Contribution. Series ratings shall not be used
> where
> (1) Motors are connected on the load side of the higher rated overcurrent device and on the line side of the lower-rated overcurrent device, and
> (2) The sum of the motor full-load currents exceeds 1 percent of the interrupting rating of the lower-rated circuit breaker.


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## Pete m.

Whether Canadian or US... the physics remain the same. Either you have a fully rated system (meaning the whole system can withstand the available fault current) or you have a tested and listed series rated system (which means that the OCPD that is closest to the source will protect the OCPD's that are downstream).

You have to have one or the other... if not you have a bad design.

Pete


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## Big John

Agreed. I don't know the first thing about Canadian code, but I know that even Canadian fuses can still explode if subjected to a fault far outside their interrupting rating.


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## l0sts0ul

This is why I'm asking but I can't seem to find out how to figure this out. 

There is a lot of great advice here but it's a little scattered for me. I need a breakdown here of how to approach this. 

Thanks


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## hardworkingstiff

l0sts0ul said:


> This is why I'm asking but I can't seem to find out how to figure this out.
> 
> There is a lot of great advice here but it's a little scattered for me. I need a breakdown here of how to approach this.
> 
> Thanks


I think you just stated the reason you should consider hiring someone to do this calculation.

If you are doing this yourself, I don't see how you can go anywhere until the PoCo gives you the available fault current.


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## l0sts0ul

I listed earlier that the poco won't give me the %iz of the transformer feeding the building mostly because the engineering department doesn't know the exact value. I'm told to assume it's 2%. 

They did tell me in their published book that it has to be no less than 22ka Rma aic rated.


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## hardworkingstiff

l0sts0ul said:


> I listed earlier that the poco won't give me the %iz of the transformer feeding the building mostly because the engineering department doesn't know the exact value. I'm told to assume it's 2%.
> 
> They did tell me in their published book that it has to be no less than 22ka Rma aic rated.


Well your PoCo sucks. Everyone I've dealt with has understood that I need to size equipment and I get a number, even if it's a little high.

Edit: Well that may be even more of a reason to hire someone that has done this before.


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## l0sts0ul

deleted


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## Pharon

l0sts0ul said:


> I listed earlier that the poco won't give me the %iz of the transformer feeding the building mostly because the engineering department doesn't know the exact value. I'm told to assume it's 2%.
> 
> They did tell me in their published book that it has to be no less than 22ka Rma aic rated.


This makes no sense. With a 600V wye secondary, the max fault current you can get on a 300kVA, 2%Z is 14,434A, and that's assuming infinite bus on the primary.

If it were me, I'd size my 600V equipment using the next higher standard rating AIC (22k?) and if you install a 600-208/120V wye 150kVA, 5.75%Z xfmr downstream, then 10kA equipment is fine for that stuff.


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## Big John

Pharon said:


> This makes no sense....


 I don't understand. You admit he could well be over 10kA AFC but you don't think he should be required to use 22kAIC?


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## Pharon

Big John said:


> I don't understand. You admit he could well be over 10kA AFC but you don't think he should be required to use 22kAIC?


No, I think I misread what POCO meant when they said "no less than 22kA" - I thought they were saying available fault current by that, but they probably meant equipment rating. I guess that's the next range up.

I did say he should use 22kA for the 600V stuff.


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## hardworkingstiff

Do they even make 600V equipment in 10kaic?


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## Meadow

Pharon said:


> The only real missing piece here is the POCO transformer impedance. Once you have that, you can figure out if 10kAIC is good enough for your subpanel OCPDs.


Almost, conductor size and length plays a huge role.


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## Meadow

This is might help:

http://www.alabamapower.com/business/services/architects-engineers/pdf/A%20E%20Fault%20Currents%20Tables%20FINAL%208%202003.pdf


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