article 551

[sparkyy]

how many 50 amp 125/250 rv sites can be fed from a 200 amp single phase service.

 

[charlie]

Welcome to the Forum!​

A poll is not required to crack open the code and look at 551.73. :smile:

 

[raider1]

Is this a test question?

By the way welcome to the forum.

Chris

 

[480sparky]

What do you think is the correct answer?
And, welcome to the zoo.... err, forum!

 

[sparkyy]

nec 551

nec 551

can i use 100% or 80% of the 200 amps

 

[charlie]

can I use 100% or 80% . . .

When doing load calculations, you may use 100% of the service size. It is the load at 100% plus 125% of the continuous loads. In an RV park, the loads would all be non-continuous. :smile:

 

[sparkyy]

nec 551

nec 551

the correct answer is 9 nine 50 amp 125/250v rv sites on a 200 amp 120/240 single phase service.

 

[hardworkingstiff]

the correct answer is 9 nine 50 amp 125/250v rv sites on a 200 amp 120/240 single phase service.

9 * 50-amps = 450-amps.

Table 551.73 shows 9 sites (receptacles) may use a demand factor of 55%.

450-amps * 55% = 247.5-amp service requirement.

7*50=350*55%=192.5

7 seems to be the answer.

Did I miss something?

 

[Twoskinsoneman]

9 * 50-amps = 450-amps.

Table 551.73 shows 9 sites (receptacles) may use a demand factor of 55%.

450-amps * 55% = 247.5-amp service requirement.

7*50=350*55%=192.5

7 seems to be the answer.

Did I miss something?

551.73 Calculated Load.
(A) Basis of Calculations. Electrical services and feeders
shall be calculated on the basis of not less than 9600 voltamperes
per site equipped with 50-ampere,

9600 * 55% is 5280va per 50amp.
200a * 240v is 48000 available va
48000va / 5280va per 50amp is lil over 9 of em.

 

[hardworkingstiff]

551.73 Calculated Load.
(A) Basis of Calculations. Electrical services and feeders
shall be calculated on the basis of not less than 9600 voltamperes
per site equipped with 50-ampere,

9600 * 55% is 5280va per 50amp.
200a * 240v is 48000 available va
48000va / 5280va per 50amp is lil over 9 of em.

Thanks, I need to slow down and read the WHOLE article I see.

I wish we had this in the 555 section.

 

[charlie]

Is this a test question? . .

We are curious, is this a test or homework question?

 

[iwire]

I wish we had this in the 555 section.

No doubt.


But really I wonder why they do not, maybe a slam dunk proposal for you to put in.

 

[hardworkingstiff]

No doubt.


But really I wonder why they do not, maybe a slam dunk proposal for you to put in.

I'm waiting to see how my proposal this year is dealt with.

 

[charlie]

. . . maybe a slam dunk proposal for you to put in.

Reason says you are correct; however, there has to be some documentation as to the diversity and loads to be used. The CMP will not just accept the statement that it will be the same as in 551.73. :smile: