Questions on COPS

[charlie b]

A load is not ?emergency? unless some governmental agency declares it to be so. One example is that building codes have declared egress lights to be emergency loads. The rules tell us that if utility power is lost, the egress lights must remain on for 90 minutes. Clearly, the intent is to give the occupants a safely illuminated path for exiting the building. Since your building?s occupants are not going to want to exit the building, you will need more than a simple battery backup for the egress lights. You will need the generator to be able to prevent the batteries from taking over the lighting load. Otherwise, the batteries will run down while the building is still occupied. Later, if the generator fails, at which point the occupants will have to leave, the egress lights won?t be available. I think you can accomplish this without having to designate the backup generator as serving emergency loads. I also doubt that there are any other emergency loads in the building that would require the generator to serve as their article 700 backup source. Bottom line, I think you can get by with one ATS, as long as battery systems serve as the official backup source for anything classified as an emergency load.

 

[charlie b]

As I see it, there are four possibilities where both Article 700 and 708 apply:
(1) An Emergency load is also a COPS load.

I don't think that is possible. But I will get to that in a second.

But let?s first agree on what might be meant by ?COPS load.? The phrase is actually meaningless, since ?COPS? is the power supply system. But there will be loads within the facility that must remain in service, in order for the occupants to be able to perform the functions that justified the COPS designation in the first place. The radio communication system comes to mind. But even if the entire building is backed up by the generator, the occupants do not require the availability of the GFCI receptacle in the bathroom, in order to perform their duties.

I now submit that the occupants do not need the egress lights, in order to perform their duties. If things come down to them needing the egress lights, then other circumstances will have already prevented them from performing any of their duties that were supported by electrical power that had come via the COPS distribution system. Thus, the ?emergency load? called ?egress lights? is not a COPS load. I believe that similar reasoning can be applied to any other load that would have been classified, by some governmental agency, as an emergency load.

 

[charlie b]

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

My RCDD colleague tells me it is a surge protection device installed at the telecommunication system's building entrance equipment. The secondary protection comes at the modules immediately downstream.

 

[charlie b]

The owner wants the entire building to be the DCOA

Has the owner created (or hired you to create) the ?facility engineering documentation establishing the necessity for such a system?? See the second paragraph under 708.1. Has the owner performed (or hired you to perform) the risk assessment addressed under 708.4? Just asking.

 

[Smart $]

I don't think that is possible. But I will get to that in a second.

But let?s first agree on what might be meant by ?COPS load.? The phrase is actually meaningless, since ?COPS? is the power supply system. But there will be loads within the facility that must remain in service, in order for the occupants to be able to perform the functions that justified the COPS designation in the first place. The radio communication system comes to mind. But even if the entire building is backed up by the generator, the occupants do not require the availability of the GFCI receptacle in the bathroom, in order to perform their duties.

I now submit that the occupants do not need the egress lights, in order to perform their duties. If things come down to them needing the egress lights, then other circumstances will have already prevented them from performing any of their duties that were supported by electrical power that had come via the COPS distribution system. Thus, the ?emergency load? called ?egress lights? is not a COPS load. I believe that similar reasoning can be applied to any other load that would have been classified, by some governmental agency, as an emergency load.

I have to disagree. While the DCOA definition says areas within a facility or site, it is possible the entire site could be DCOA. As such, emergency egress lighting would be included in the COPS.

Also, I do not see any stipulation that says a "non-essential" load cannot be on the COPS. A COPS can have emergency, legally required, optional standby, and/or parallel power production subsystems, for which the respective Articles will apply concurrently.