SCCR Responsibility Question

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necnotevenclose

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When equipment is ordered and installed with an incorrect nameplate it causes several issues. When those issues come up, the equipment manufacture usually looks to electrical to provide a solution. Depending on your AHJ, that electrical solution may prohibit you to use current limiting fuses. When this has come up, a 3rd party testing agency has had to be hired to prove and relabel the equipment which delayed the C of O date and increased cost since components may need to get changed out. In my opinion this could be best avoided during design and ordering of the equipment.

With the changes of NEC and UL 1995 electrical inspectors are verifying more & more (its good thing) that the installed equipment (where required to comply with) is listed with a SCCR rating that meets or exceed the available fault current. I've been running more and more short circuit calcs to show what the calculated value at equipment, and even showing that information on plans. The problem is that information can still get looked over.

So my question is who is responsible for making sure the equipment that is ordered/installed has the appropriate SCCR rating?

Is it the GC, EC, MC, Elev. Contractor, Fire Protection Contractor, Electrical Engineer?
 
I think it could be just about anybody if it were to come down to a court decision, whoever presents the best case wins.

When it comes down to an inspector failing the installation, the EC or other responsible for installation is who the inspector is likely going to go to first, or depending on who actually files permits possibly the owner or a GC.
 
necnotevenclose said:
When equipment is ordered and installed with an incorrect nameplate it causes several issues...

Is it the GC, EC, MC, Elev. Contractor, Fire Protection Contractor, Electrical Engineer?
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Are you saying the manufacturer put an incorrect plate on the equipment?
 
I am not entirely sure what your point is.

Are you asking who is responsible financially if equipment is ordered that is inappropriate?

It depends on a lot of things. We have sold a lot of stuff that has 5 or 10 kA SCCR over the years. My guess is at least a fair amount of it should have had a higher rating. if the purchaser does not know enough to know that he needs something with a higher SCCR rating how is he going to tell the supplier?

In the end, it is up to the owner to make sure the equipment is appropriate. Who his agent(s) is(are) in getting there varies widely.

Incidentally, adding current limiting fuses is not going to solve the problem in many cases, despite the wide spread belief that it does.
 
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petersonra said:
I am not entirely sure what your point is.

Are you asking who is responsible financially if equipment is ordered that is inappropriate?

It depends on a lot of things. We have sold a lot of stuff that has 5 or 10 kA SCCR over the years. My guess is at least a fair amount of it should have had a higher rating. if the purchaser does not know enough to know that he needs something with a higher SCCR rating how is he going to tell the supplier?

In the end, it is up to the owner to make sure the equipment is appropriate. Who his agent(s) is(are) in getting there varies widely.
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And the very odd situation of the equipment being specified, ordered, and delivered correctly, but with the wrong descriptive label installed, seems to fall right into the manufacturer's court, probably including the cost of getting the equipment relabeled in the field.
 
GoldDigger said:
And the very odd situation of the equipment being specified, ordered, and delivered correctly, but with the wrong descriptive label installed, seems to fall right into the manufacturer's court, probably including the cost of getting the equipment relabeled in the field.
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if it is just a labeling issue it is not real hard to fix it.
 
petersonra said:
I am not entirely sure what your point is.

Are you asking who is responsible financially if equipment is ordered that is inappropriate?

It depends on a lot of things. We have sold a lot of stuff that has 5 or 10 kA SCCR over the years. My guess is at least a fair amount of it should have had a higher rating. if the purchaser does not know enough to know that he needs something with a higher SCCR rating how is he going to tell the supplier?

In the end, it is up to the owner to make sure the equipment is appropriate. Who his agent(s) is(are) in getting there varies widely.

Incidentally, adding current limiting fuses is not going to solve the problem in many cases, despite the wide spread belief that it does.
Click to expand...
You can always make the circuit longer to reduce available fault current.

Run a cable or raceway around the room a few times if necessary:happyyes:
 
necnotevenclose said:
When equipment is ordered and installed with an incorrect nameplate it causes several issues. When those issues come up, the equipment manufacture usually looks to electrical to provide a solution. Depending on your AHJ, that electrical solution may prohibit you to use current limiting fuses. When this has come up, a 3rd party testing agency has had to be hired to prove and relabel the equipment which delayed the C of O date and increased cost since components may need to get changed out. In my opinion this could be best avoided during design and ordering of the equipment.

With the changes of NEC and UL 1995 electrical inspectors are verifying more & more (its good thing) that the installed equipment (where required to comply with) is listed with a SCCR rating that meets or exceed the available fault current. I've been running more and more short circuit calcs to show what the calculated value at equipment, and even showing that information on plans. The problem is that information can still get looked over.

So my question is who is responsible for making sure the equipment that is ordered/installed has the appropriate SCCR rating?

Is it the GC, EC, MC, Elev. Contractor, Fire Protection Contractor, Electrical Engineer?
Click to expand...

GC = Never; Always has bullet proof contract and lawyers.
EC = As you stated in the question ordered/installed not as designed? Is there a calc? If they did not do due diligence of contacting engineer for calcs or ignored calcs YES Most likely. Or if no Electrical Engineer = YES (they are the engineer by default). IF they did not provide the Engineer and the calcs were wrong and equipment ordered as per calcs then no.

MC? Mechanical contractor ? Not unless they are ordering HVAC panels. or they did not do due diligence of contacting engineer for calcs.
Elev. Contractor: not unless it is in the elevator room or they did not do due diligence of contacting engineer for calcs.
Fire Protection Contractor: definitely not
Electrical Engineer = Yes but not likely; If they are involved then likely since they design the project, if they omit specifications of fault current the error of omision is the Engineer. Or they did not do due diligence of overseeing what they designed. However they probably have a bid states they design only and explicitly states they will not oversee the actual construction unless an additional fee is paid.
 
If the gear was supplied with an incorrect NP, which you n know to happen, it is a warranty issue which is to be addressed by the manufacturers authorized providers. NPs are sacred and are not to be changed or altered in any way.
The AHJ should demand that the manufacturer is to correct the discrepancy.
The problem may have originated from engineering with an incorrect NP drawing which was carried through to the person who made the NP. If it originated in engineering the QC may have any reason to question the NP because that what was on the drawing.
If the NP did not comply with the drawing the it should have been caught in QC.
In any event it is a warranty issue. Usually the design should be confirmed through an engineering review and the confirmed by authorized field service before a replacement NP is to be installed.
 
petersonra said:
NPs are not sacred.
The NP can be changed in the field just like any other part
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Yes, in one case, NP of higher rating than actual rating for a gen set was fixed on the gen set by an EC to earn more money for his product by unfair means.
 
petersonra said:
NPs are not sacred. The UL sticker is closer to being sacred.

The NP can be changed in the field just like any other part found to have a factory defect.
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Is that so. I worked for 3 manufactures and, yes, NPs are sacred. The NP reflects what was manufactured. If the NP is incorrect or must be verified as such. An incorrect NP is not simply a factory defect. The UL label may be a misrepresentation of the assemblies UL listing. If the NP is incorrect the UL label should not of been attached to the assembly. If the NP is corrected the assembly must be inspected and the verified that the NP complies with what has been built. Then the question remains was the UL attached to an assembly that may not have been built to UL requirements which includes an incorrect NP. Did that violate UL? As I related in my previous post there are a number of reasons that an incorrect NP was made. It may no be as simple as replacing the NP but often includes documentation including drawings. As such an enter set of drawing may be necessary for correct documentation.
I know for a fact that from my experience that a NP can not be simply remade, mailed, and installing in the field.
 
templdl said:
Is that so. I worked for 3 manufactures and, yes, NPs are sacred. The NP reflects what was manufactured. If the NP is incorrect or must be verified as such. An incorrect NP is not simply a factory defect. The UL label may be a misrepresentation of the assemblies UL listing. If the NP is incorrect the UL label should not of been attached to the assembly. If the NP is corrected the assembly must be inspected and the verified that the NP complies with what has been built. Then the question remains was the UL attached to an assembly that may not have been built to UL requirements which includes an incorrect NP. Did that violate UL? As I related in my previous post there are a number of reasons that an incorrect NP was made. It may no be as simple as replacing the NP but often includes documentation including drawings. As such an enter set of drawing may be necessary for correct documentation.
I know for a fact that from my experience that a NP can not be simply remade, mailed, and installing in the field.
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It is possible that there are cases where this is true, but if the wrong NP was applied at the factory, it is not a big deal to just get a new one. Just who can install the correct NP might be an issue as in some cases UL may only allow the manufacturer to do so, but it just is not that big of a deal to replace an incorrect NP.

Now, if as you seem to be suggesting in your post there is more going on than just the wrong NP being applied, there are likely to be other things that have to happen.
 
petersonra said:
It is possible that there are cases where this is true, but if the wrong NP was applied at the factory, it is not a big deal to just get a new one. Just who can install the correct NP might be an issue as in some cases UL may only allow the manufacturer to do so, but it just is not that big of a deal to replace an incorrect NP.
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There can also be the factor that once you have (deservedly) gotten the inspector's attention, he may be looking at everything more closely. :)
 
petersonra said:
Now, if as you seem to be suggesting in your post there is more going on than just the wrong NP being applied, there are likely to be other things that have to happen.
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An incorrect NP is very serious issue. It could be as a result of a simple typo as a result of the NP making process. Anytime there is a suspicion the there is an incorrect NP then the rest of the assembly is suspect.

As an example if it were to be a panel or switchboard there could be a difference in the way the bus and/or connectors are insulated between 240 and 480v. With a set of 240v panels that I once sold most were built according to 240v insulating requirements and there were a few tat had been built with 600v insulation. The customer thought that we omitted insulation on the 240v panel boards. Which were actually built correctly. As such we provided 600v insulation for the 240v panels instead of trying to convince the customer that the 240v panels were built correctly.
MCCs, switchboard and other gear with bus SCCRs are and issue where the way the bus is supported can make a difference in the heard SCCR.
Yes, a incorrect NP can require an engineering review to assure that the product has been in fact been built as specified per the order entry and that the drawings are in fact correct..
 
templdl said:
Yes, a incorrect NP can require an engineering review to assure that the product has been in fact been built as specified per the order entry and that the drawings are in fact correct..
Click to expand...

and after the engineer spends the 5 minutes it takes in determining that indeed the NP is all that is wrong, he signs a requisition for a new NP and it gets sets out to be installed.

we are talking about the WRONG NP here. Not something wrong with the design.
 
petersonra said:
and after the engineer spends the 5 minutes it takes in determining that indeed the NP is all that is wrong, he signs a requisition for a new NP and it gets sets out to be installed.

we are talking about the WRONG NP here. Not something wrong with the design.
Click to expand...

It may be as simple as that. :)
 
Here is my experience as an electrical engineer;

For most projects you can get available fault info during design, from the utility . With this info, you make nice tight bid documents by specifying the required SC duty of your equipment. The POCO in our area publishes values for certain standard voltages and kVA's. Our panel schedules have a line to fill in with the AIC rating.

For some projects, no utility data is available, like for a development that they haven't even designed yet. In this case, I will estimate a SC duty and specify it (conservatively) with a disclaimer that the contractor has to confirm it with the utility company. This way I'm confident that if anybody down the line drops the ball, we're safe.

Lastly, there seems to be a trend in the business to require a SC and Arc-Flash study be done by the contractor. I don't like to do it that way because I like to be the guy getting paid to do it :). If you require the contractor to do a study, then you had better not put an AIC rating on anything unless you're absolutley sure. (Sometimes the 480-208 V transformers make it a slam-dunk.)

In no case is it good engineering practice to simply assume that someone else will figure it out and do the right thing.
 
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