Questions on COPS

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mshields

mshields

Senior Member
Location
Boston, MA
I've been asked to work on adding a generator to a police station and to make it COPS compliant. i.e. meeting the requirements of NEC Article 708.

I've not done a COPS facility since this section was added to the code. Having just reviewed the Article I had some questions I was hoping you could help me with - here goes:

1. Bearing in mind that they want the whole facility to be the DCOA, I believe I need two ATS's; A life Safety and a COPS for in this case all of the rest of the facility. I'm wondering if I can get away with just a single ATS?

2. I find it curious that two levels of ground fault are required for Feeders meeting the standard service and feeder requirements (namely 1000V and more than 150V to ground). Does this apply to the load side of the ATS's? Or does it only apply to the normal feeders within a building that is deemed a COPS facility.

3. 708.14(4) - What is the "protector" they are referring to.


Thanks,

Mike
 
mshields said:
1. Bearing in mind that they want the whole facility to be the DCOA, I believe I need two ATS's; A life Safety and a COPS for in this case all of the rest of the facility. I'm wondering if I can get away with just a single ATS?
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I'm not seeing where life safety is required under Article 708. Is it a carryover from also having an Article 700 application?
 
mshields said:
2. I find it curious that two levels of ground fault are required for Feeders meeting the standard service and feeder requirements (namely 1000V and more than 150V to ground). Does this apply to the load side of the ATS's? Or does it only apply to the normal feeders within a building that is deemed a COPS facility.
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Depends on where the ATS is located in the system. First part of the determination is whether GFP is provided, whether required [230.95, 215.10] or not. The next level of feeders also require GFP to open their OCPD on GF. If the ATS is located in between, then yes on the load side.
 
mshields said:
1. Bearing in mind that they want the whole facility to be the DCOA, I believe I need two ATS's; A life Safety and a COPS for in this case all of the rest of the facility. I'm wondering if I can get away with just a single ATS?
Click to expand...
I might not be right about this, but I prefer to use the phrase "life safety" in no other context than at a health care facility. In all other facilities for which a backup power source is required for reasons that impact the safety of human life, I use the phrase "emergency," and look to article 700 for guidance.

Article 708 clouds that distinction, however. For example, it requires that any transfer switch that will supply DCOA loads be listed for emergency use. That does not by itself bring article 700 into play.

My answer to your question is that I believe two separate ATSs would be needed, if and only if you plan to use the backup generator to supply emergency loads (e.g., egress lights). That is because article 700 would require the separate ATS, not because of anything in 708.
 
charlie b said:
...My answer to your question is that I believe two separate ATSs would be needed, if and only if you plan to use the backup generator to supply emergency loads (e.g., egress lights). That is because article 700 would require the separate ATS, not because of anything in 708.
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IMO, the facility has to be legally required to have an emergency system first. A legally required COPS does not automatically infer an emergency system is legally required.
 
Smart $ said:
IMO, the facility has to be legally required to have an emergency system first. A legally required COPS does not automatically infer an emergency system is legally required.
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First of all, please don't open the door to confusion by using phrases in close proximity where they could have different meanings in other context. What I mean is that the phrase "legally required" has found a home in article 701, and the word "emergency" has found a home in article 700. Please let's not let the twain ever meet.

Secondly, I said "if you plan. . . ." If there is a requirement for egress lights, and if Mike plans to power them from the generator, then he would find himself in article 700. Again, I said "if."

 
See 700.26 and 701.26 and 708.52 for ground fault protection for equipment.

You would only have alarms for the generator side of 700 and 701 systems.

In my opinion, it would not be the best design to install GFP on the load side of any transfer switch. And it would probably be a code violation for 700 or 701 systems.

I'm not sure how large of a generator you have, but you can always subdivide loads so the ATS feeders aren't large enough to need GFP.
 
lots of great input

lots of great input

first off - yes - agreed. Emergency belongs to Article 700. Life safety as one of three EES branches.

This thing is complicated by the fact that it is an existing building. I haven't seen this building yet by the way. Will do so tomorrow. But if the entire electrical system is to be part of a COPS system, the every panelboard needs to be in a 2 hour rated room. I could get lucky and find that they're in a concrete room but if not, I'll have to work it out with the AHJ

The owner wants the entire building to be the DCOA so I'll either be putting in a COPS ATS plus Emergency ATS or just the COPS OR just the COPS plus battery packs to meet the Article 700 egress requirements and Exit signs.

I favor the latter approach as COPS gives them 72 hours of backup power and the battery packs provide a lieu pole.

With regard to the two levels of GFCI, I'm inclined not to put a second level in if it's down stream of the ATS but will plan to discuss it with the AHJ during design. This is young code section. I'm thinking this wasn't fully thought out.

Lastly Charlie - thank you for nearly not pointing out the pun.

Mike
 
charlie b said:
First of all, please don't open the door to confusion by using phrases in close proximity where they could have different meanings in other context. What I mean is that the phrase "legally required" has found a home in article 701, and the word "emergency" has found a home in article 700. Please let's not let the twain ever meet.

Secondly, I said "if you plan. . . ." If there is a requirement for egress lights, and if Mike plans to power them from the generator, then he would find himself in article 700. Again, I said "if."
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I'll try to appease your sensibility on the matter, sir... :D

Article 700 applications are authority mandated. Article 708 can be authority mandated or documented engineering rationale. For mandated, I have no idea whether it can be both or has to be one or the other. What I'm eluding to is if both can apply, I don't see anything in the Code itself that states an Article 700 application must be entirely independent of the Article 708 application. Consider a COPS facility that provides emergency services, e.g. 911, police, fire dept., and other first-response type.
 
Smart $ said:
I'll try to appease your sensibility on the matter, sir... :D

Article 700 applications are authority mandated. Article 708 can be authority mandated or documented engineering rationale. For mandated, I have no idea whether it can be both or has to be one or the other. What I'm eluding to is if both can apply, I don't see anything in the Code itself that states an Article 700 application must be entirely independent of the Article 708 application. Consider a COPS facility that provides emergency services, e.g. 911, police, fire dept., and other first-response type.
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I'm not sure I see your point.
This section says don't mix COPS with Emergency:
Wiring from an emergency source or emergency source distribution overcurrent protection to emergency loads shall be kept entirely independent of all other wiring and equipment, unless otherwise permitted in (1)through(5):

I'm quoting from the 2011 and it looks like more work is needed. There should a mention of 708 in 700 like there is mention of 700 in 708.

There s no mention of 708 in 700 under selective pick up but 700 is mentioned in 708 under selective pick up.

Could be other hiccups like that.
 
sandsnow said:
I'm not sure I see your point.
This section says don't mix COPS with Emergency:
Wiring from an emergency source or emergency source distribution overcurrent protection to emergency loads shall be kept entirely independent of all other wiring and equipment, unless otherwise permitted in (1)through(5):

I'm quoting from the 2011 and it looks like more work is needed. There should a mention of 708 in 700 like there is mention of 700 in 708.

There s no mention of 708 in 700 under selective pick up but 700 is mentioned in 708 under selective pick up.

Could be other hiccups like that.
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The subtopic is separate ATS for each Emergency and COPS. So let's examine the pertinent part of 708.22 on selective pickup...
The alternate power source shall be permitted
to supply COPS emergency, legally required standby,
and optional loads where the source has adequate capacity
or where automatic selective load pickup and load shedding
is provided as needed to ensure adequate power to (1) the
COPS and emergency circuits, (2) the legally required
standby circuits, and (3) the optional standby circuits, in
that order of priority
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Seems to me that Emergency Systems and COPS are neither mutually exclusive or inclusive.

So let's say the facility in its entirety is Emergency and COPS/DCOA (mutually inclusive by designation). For this scenario, I'd say Emergency and COPS circuits are one and the same. No need for separate ATS. Yet this is only one out of potentially many possible scenarios. Each requires evaluation to determine if any separation of circuits is required.
 
why adhere to COPS to begin with?

why adhere to COPS to begin with?

This police station I'm adding a generator to. It's a Project Manager for this client who suggested that they should adhere to NEC 708 BUT why should they.

Is this a strictly voluntary code section. This is a college campus police station. That they want a standby generator to keep them up and running is perfectly understandable, but meeting all of the requirements of 708 strikes me as not worth the expense.

What's more, isn't a facility with COPS, a description of the electrical system, supposed to go with other requirements external to the electrical system. i.e. wouldn't one start out seeking to build something complying with NFPA 1600 as a first step, designing an electrical system to 708 as a second?

What do you think?
 
Smart $ said:
The subtopic is separate ATS for each Emergency and COPS. So let's examine the pertinent part of 708.22 on selective pickup...

Seems to me that Emergency Systems and COPS are neither mutually exclusive or inclusive.

So let's say the facility in its entirety is Emergency and COPS/DCOA (mutually inclusive by designation). For this scenario, I'd say Emergency and COPS circuits are one and the same. No need for separate ATS. Yet this is only one out of potentially many possible scenarios. Each requires evaluation to determine if any separation of circuits is required.
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Look at 700.5(d) and 708.24(d). Emergency ats shall supply only emergency loads. COPS ats shall only supply COPS loads.
So the above and section I quoted before tells me the two types of loads must independent.
The selective load section in 708 tells me that 700 and 708 shall have equal priority only. To me there is nothing there about separation of wiring.
All the rules in 700 are in play unless 708 specifically says no.
 
sandsnow said:
Look at 700.5(d) and 708.24(d). Emergency ats shall supply only emergency loads. COPS ats shall only supply COPS loads.
So the above and section I quoted before tells me the two types of loads must independent.
The selective load section in 708 tells me that 700 and 708 shall have equal priority only. To me there is nothing there about separation of wiring.
All the rules in 700 are in play unless 708 specifically says no.
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My only problem with your position is you are looking at these systems as mutually exclusive. There is no such stipulation in the sections you cite. As I see it, there are four possibilities where both Article 700 and 708 apply:
(1) An Emergency load is also a COPS load.
(2) An Emergency load is not a COPS load.
(3) A COPS load is not an Emergency load.
(4) A normal load, neither Emergency nor COPS.
Where only (1) exists, only one ATS is required. Where any combination of (1), (2), and (3) exists, that many ATS will be required.
 
sandsnow said:
Look at 700.5(d) and 708.24(d). Emergency ats shall supply only emergency loads. COPS ats shall only supply COPS loads.
So the above and section I quoted before tells me the two types of loads must independent.
The selective load section in 708 tells me that 700 and 708 shall have equal priority only. To me there is nothing there about separation of wiring.
All the rules in 700 are in play unless 708 specifically says no.
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708.10 Feeder and Branch Circuit Wiring
(B) Wiring. Wiring of two or more COPS circuits supplied from the same source shall be permitted in the same raceway, cable, box, or cabinet. Wiring from a COPS source or COPS source distribution overcurrent protect ion to critical loads shall be kept entirely independent of all other wiring and equipment.
Exception: Where the COPS feeder is installed in transfer equipment enclosures.

Certainly an alternate power source is permitted to supply "COPS emergency, legally required standby, and optional loads" but it appears there should be an independant ATS designated for feeding equipment & branch circuits of the COPS. If you choose to have an alternate power source that supplies other systems other than COPS, and you choose to have an ATS for the transfer then the 2nd ATS is needed per 708.24(D). IMO
 
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Smart $ said:
My only problem with your position is you are looking at these systems as mutually exclusive. There is no such stipulation in the sections you cite. As I see it, there are four possibilities where both Article 700 and 708 apply:
(1) An Emergency load is also a COPS load.
(2) An Emergency load is not a COPS load.
(3) A COPS load is not an Emergency load.
(4) A normal load, neither Emergency nor COPS.
Where only (1) exists, only one ATS is required. Where any combination of (1), (2), and (3) exists, that many ATS will be required.
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Actually we agree.
If 1 is true, then only one ats.
 
mwm1752 said:
708.10 Feeder and Branch Circuit Wiring
(B) Wiring. Wiring of two or more COPS circuits supplied from the same source shall be permitted in the same raceway, cable, box, or cabinet. Wiring from a COPS source or COPS source distribution overcurrent protect ion to critical loads shall be kept entirely independent of all other wiring and equipment.
Exception: Where the COPS feeder is installed in transfer equipment enclosures.

Certainly an alternate power source is permitted to supply "COPS emergency, legally required standby, and optional loads" but it appears there should be an independant ATS designated for feeding equipment & branch circuits of the COPS. If you choose to have an alternate power source that supplies other systems other than COPS, and you choose to have an ATS for the transfer then the 2nd ATS is needed per 708.24(D). IMO
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I agree with that, unless the load is both a COPS and EM load
 
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