45 Wall Mounted TV's

[jxofaltrds]

So how many duplex recept's will power two TV's?

Calculations say...

45 ? 100VA ea = 4500VA
4500VA ? 1920VA max/ckt = 3 ckt's minimum

If we say13 duplex max per ckt, that'll get him 39 with potential to plug in 78 TV's... but every duplex where two are plugged in have to be calculated at 200VA.
While there is potential to plug other loads into duplexes with only one TV, I don't believe 210.23(A)(2) applies because these are not general-use receptacles ? most likely installed high up on wall, and ceilings are likely out of reach for most ? but Code doesn't say this...

Where did you get 200?

 

[Smart $]

Where did you get 200?

Quote at end of OP says the TV is rated 100VA.... times 2 is 200VA.

 

[Dennis Alwon]

Here is my opinion on it if anyone cares.

If this were a code question we would have to work with the info given. IMO, that would mean we would have to consider the load continuous and at 100va for each TV. I don't see where the NEC allows us the convenience to adjust because the TV's may not be at max wattage all the time and since there is no way to guess it we must use 100va.

In terms of the extra receptacles. Let's look at 2 garage doors wired with the outlets in the garage on the same circuit. IMO, the extra garage receptacles do not have anything necessarily plugged into place but they could and therefore the circuit would have to follow the 50% rule of 210.23(A)(2). What are those other outlets for if not for a cord and plug connected piece of equipment. I am not convinced because the equipment is not in place that the calculation should change.

Certainly in a concession stand there could be fans etc plugged into the outlets as well. I realize that this is not a popular thought but I also don't think the code is clear on this.

 

[__dan]

if anyone cares.

I thought we were beyond caring and into /i beating_dead_horse.avi /i

I agree the load can be expected to run more than three hours and in a commercial setting, someone will come along and plug a shop vac into it. The assumption (in the future, by the user) will be that the receptacle will take a 15 amp load. The NEC allows leniency in this assumption for multiple outlets on the same circuit. Most users will assume they can load the circuit up to the point the breaker trips.

Same thing happens with track light in retail when the manager decides he needs more light, they can make the thing look like a Christmas tree.

 

[infinity]

I would say that a TV IS a continous load in this application.
Virtualy certain to be on throughout the working day, much longer than 3 hours. The loading of most modern TVs varies only very slightly by programe content and can IMHO be regarded as continous.

It would therefore seem to me that if the outlets are out of easy reach and unlikely to be used for anything else, then the circuits could be designed for up to but not exceeding, 16 amps on a 20 amp circuit.

It would however IMHO be a better design to limit the number of TV sets per circuit to a much lower value than that. Consider firstly the inrush current after a brief power failure, and secondly the loss of trade or reputation if a fault in one TV trips the breaker and puts many others out.
Better to have few per circuit in that cases.

It's not possible for a TV to be continuous load by the definition in Article 100:

Continuous Load. A load where the maximum current is
expected to continue for 3 hours or more.

 

[Smart $]

Here is my opinion on it if anyone cares.

... I also don't think the code is clear on this.

I agree with that opinion...

 

[kwired]

I would say that a TV IS a continous load in this application.
Virtualy certain to be on throughout the working day, much longer than 3 hours. The loading of most modern TVs varies only very slightly by programe content and can IMHO be regarded as continous.

It would therefore seem to me that if the outlets are out of easy reach and unlikely to be used for anything else, then the circuits could be designed for up to but not exceeding, 16 amps on a 20 amp circuit.

It would however IMHO be a better design to limit the number of TV sets per circuit to a much lower value than that. Consider firstly the inrush current after a brief power failure, and secondly the loss of trade or reputation if a fault in one TV trips the breaker and puts many others out.
Better to have few per circuit in that cases.

Put a motor driven appliance(s) on similar circuit and you may have just as much or even more inrush current. That is a design factor that may not come up until after original install IMO.

I thought we were beyond caring and into /i beating_dead_horse.avi /i

I agree the load can be expected to run more than three hours and in a commercial setting, someone will come along and plug a shop vac into it. The assumption (in the future, by the user) will be that the receptacle will take a 15 amp load. The NEC allows leniency in this assumption for multiple outlets on the same circuit. Most users will assume they can load the circuit up to the point the breaker trips.

Same thing happens with track light in retail when the manager decides he needs more light, they can make the thing look like a Christmas tree.

If this were a bar with a lot of TV's ... that vacuum very well could be plugged in to that circuit, it also very well may be after hours and the TV's are not running.

They could also plug the same vacuum into some other outlet and overload that circuit that doesn't necessarily have outlets dedicated to specific equipment. Overload protection is kind of the number one feature of the breaker, users will learn what they can not plug in, or if they feel they must use an item in a particular place that trips when doing so maybe they finally call an electrician to make it so they can do what they wish - and hopefully he is competent enough to install additional circuits and not just increase the breaker size.

It's not possible for a TV to be continuous load by the definition in Article 100:

Continuous Load. A load where the maximum current is
expected to continue for 3 hours or more.

Is a motor that is not considered fully loaded still considered a continuous load then?

How about lighting on a dimmer switch?


Maybe that definition needs some tweaking.