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Discussion Starter · #1 ·
It seems more and more projects the engineers are asking for this. I'm just wondering if this is everywhere and Manitoba is just catching up with safety? Or is this fairly new to everyone? I know it is based on the size of a project and distribution/service size but what are the costs you are seeing. The pricing I am getting and having to pay seems outrageous!
 

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It seems more and more projects the engineers are asking for this. I'm just wondering if this is everywhere and Manitoba is just catching up with safety? Or is this fairly new to everyone? I know it is based on the size of a project and distribution/service size but what are the costs you are seeing. The pricing I am getting and having to pay seems outrageous!
There are places out here that have been dealing with Arc Flash studies for about 4-5 years.. Some are still in the dark about it.. No idea on costs though..
 

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We ended up purchasing EasyPower software about 7 years ago for arc flash hazard analysis and labeling; it also has a lot of other capabilities such as performing short circuit and coordination studies.
 

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There are places out here that have been dealing with Arc Flash studies for about 4-5 years.. Some are still in the dark about it.. No idea on costs though..
I was doing them 14 years ago, and wasn't alone.
 

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It seems more and more projects the engineers are asking for this. I'm just wondering if this is everywhere and Manitoba is just catching up with safety? Or is this fairly new to everyone? I know it is based on the size of a project and distribution/service size but what are the costs you are seeing. The pricing I am getting and having to pay seems outrageous!
If you think an arc flash study is pricey, wait till you have to do a Z32 study for patient care area receptacles ( much bigger butt hurt )
 

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Michigan Master said:
We ended up purchasing EasyPower software about 7 years ago for arc flash hazard analysis and labeling; it also has a lot of other capabilities such as performing short circuit and coordination studies.
Just did an arc flash safety course and was told to never trust the software as there are way to many variables to get an accurate analysis.
 

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Just did an arc flash safety course and was told to never trust the software as there are way to many variables to get an accurate analysis.
Don't know exactly the context of that comment but it is true that you can not just buy software and perform an analysis. There are many variables and that is why the analysis should be done by a professional electrical engineer who has experience in this area and is familiar with IEEE 1584 and NFPA 70E.

It is not so much as trusting the software but ensuring that the individual performing the study is competent and has experience in this area.

I am a PE who has been performing arc flash studies for over 10 years and use EasyPower for industrial/commercial type installations and use Arc Pro for utility type installations where the arc flash is due primarily to an open air, vertical, single phase fault at a voltage above 15kV.
 

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It's getting pretty common. Every new site commissioning we do has a coordination study, and almost all of them include arc-flash analysis.

Some of the places offering the flash hazard studies are really out of their league, though. Seen some laughably bad stickers on panels where I really want to ask how much the customer shelled out for that.
 

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Discussion Starter · #9 ·
Big John said:
It's getting pretty common. Every new site commissioning we do has a coordination study, and almost all of them include arc-flash analysis. Some of the places offering the flash hazard studies are really out of their league, though. Seen some laughably bad stickers on panels where I really want to ask how much the customer shelled out for that.
We quoted a small project last week that was specified that we do a arc flash study and short circuit coordination and we were quoted 5k for this. This project was a small office addition with a 100A sub panel in it and was only worth 20k I total. The engineer stated that this study was only for the new panel, and if the rest on the distribution didn't already have this done he would have to do it from scratch and the cost would go up dramatically! I don't know what work is required but 5k just to do this on one 100A panel is crazy in my mind, the panel isn't even worth nearly that much.
 

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We quoted a small project last week that was specified that we do a arc flash study and short circuit coordination and we were quoted 5k for this. This project was a small office addition with a 100A sub panel in it and was only worth 20k I total. The engineer stated that this study was only for the new panel, and if the rest on the distribution didn't already have this done he would have to do it from scratch and the cost would go up dramatically! I don't know what work is required but 5k just to do this on one 100A panel is crazy in my mind, the panel isn't even worth nearly that much.

That does seem excessive for the one panel but in order to do that panel for short circuit and arc flash the available short circuit current and upstream breaker details need to be known. One cannot assume or use maximum available short circuit current for arc flash.
So, I do not know what basis the arc flash hazard would be analyzed on.

Some of the costs of a study are driven by data collection and that can be much more than the engineering time. Another adder is the overhead that is added which can be costly for large firms that have big staffs to support. There are small firms, like mine, that only have several people and myself I work out of a home office. Very little overhead.

As I noted above, I have over 10 years doing these studies and spent over 20 years in engineering for utility companies.
 

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Does the spec require an arc flash study, or simply arc flash labeling? Huge difference. There are generic stickers that say something like "Arc flash hazard - Proper PPE required". That satisfies the labeling requirement when a study isn't expressly required.

 

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I'm pretty sure it's a study. Most specs these days require arc flash studies, coordination studies, selective coordination studies and more.

Definitely things you don't want to leave out of your bid. I've seen them run $40-50k.
 

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I'm pretty sure it's a study. Most specs these days require arc flash studies, coordination studies, selective coordination studies and more.

Definitely things you don't want to leave out of your bid. I've seen them run $40-50k.
Right. But remember those stickers I posted when the spec is leaves "room for interpretation". :thumbsup:
 

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Does the spec require an arc flash study, or simply arc flash labeling? Huge difference. There are generic stickers that say something like "Arc flash hazard - Proper PPE required". That satisfies the labeling requirement when a study isn't expressly required.


So assume that this is on a 480V panel in an industrial facility, what is the Appropriate PPE?
 

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So assume that this is on a 480V panel in an industrial facility, what is the Appropriate PPE?
One would then have to reference the tables in 70E which assign a Hazard/Risk Category (HRC) based on system voltage and the task being performed.

However, a frequently overlooked factor is that in order to use the tables, the electrical system must fall into the short circuit current and fault clearing times specified in the table notes.
 

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wbdvt said:
Don't know exactly the context of that comment but it is true that you can not just buy software and perform an analysis. There are many variables and that is why the analysis should be done by a professional electrical engineer who has experience in this area and is familiar with IEEE 1584 and NFPA 70E. It is not so much as trusting the software but ensuring that the individual performing the study is competent and has experience in this area. I am a PE who has been performing arc flash studies for over 10 years and use EasyPower for industrial/commercial type installations and use Arc Pro for utility type installations where the arc flash is due primarily to an open air, vertical, single phase fault at a voltage above 15kV.
Sorry for the confusion we were told that some "training companies" are selling their own software and say anyone can perform the analysis
 

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Thank you, MM. You are making the point I was leading up to which is a definite weakness of the tables. In reference to my example above for panelboards between 240 and 600V the parameters of the tables are: maximum of 25kA fault current and a clearing time 2 cycles. This would be upstream protective device clearing time.

So, without a short circuit study done, How do you know that these parameters are being met to be able to use the table?
 

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...How do you know that these parameters are being met to be able to use the table?
It's easy to get a worst-case scenario available fault current if you know your upstream source impedance.

The part that always flummoxed me was clearing time. A lot of fuses or breakers can definitely clear within two cycles if the current is high enough, but even with a proper arc flash analysis, how do you know what the impedance of the fault is going to be? How would you ever know how quickly it was going to clear?
 

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Does the spec require an arc flash study, or simply arc flash labeling? Huge difference. There are generic stickers that say something like "Arc flash hazard - Proper PPE required". That satisfies the labeling requirement when a study isn't expressly required.

This sticker comes on most of the new panelboards that I have seen, right from the factory. And you're right, in most cases this is adequate unless a study is specified.
 

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This sticker comes on most of the new panelboards that I have seen, right from the factory. And you're right, in most cases this is adequate unless a study is specified.
The NFPA 70E would disagree....

(C) Equipment Labeling.​
Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field marked with a label
containing all the following information:

(1) Only one of the following:
a. Available incident energy

b. Minimum arc rating of clothing
(2) Date of arc flash hazard analysis
(3) Nominal system voltage

(4) Arc flash boundary
 
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