Marina Receptacle / pedestal Loads

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Npstewart

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Its been a while since we've done any marinas.

If theres a (2) Sided Marina Pedestal intended to serve (2) Boat slips, does the below calculation for this single pedestal seem correct?

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Side 1:
50A @ 240V + 50A @ 240V + 100A @ 240V

Side 2:
50A @ 240V + 50A @ 240V + 20A @ 120V

Total load for this Pedestal = 200 Amps @ 240v = 48kW

----


The thought process is that only (1) boat per slip could use the pedestal but (1) boat could use (2) 50A receptacles at the same time.


Now, lets say there were (6) of these pedestals. How many receptacles would this single pedestal represent? Two? So in total if there were (6) of these same pedestals, there would be (12) shore power receptacles total when referencing 555.12?
 
Npstewart said:
Its been a while since we've done any marinas.

If theres a (2) Sided Marina Pedestal intended to serve (2) Boat slips, does the below calculation for this single pedestal seem correct?

----
Side 1:
50A @ 240V + 50A @ 240V + 100A @ 240V

Side 2:
50A @ 240V + 50A @ 240V + 20A @ 120V

Total load for this Pedestal = 200 Amps @ 240v = 48kW

----


The thought process is that only (1) boat per slip could use the pedestal but (1) boat could use (2) 50A receptacles at the same time.


Now, lets say there were (6) of these pedestals. How many receptacles would this single pedestal represent? Two? So in total if there were (6) of these same pedestals, there would be (12) shore power receptacles total when referencing 555.12?
Click to expand...
I do not believe that you have the correct code section!
 
I see 5 receptacles that are required to be counted for a total connected load of 72kW on that pedestal. The table would permit you to take that load at 90%.
If you had 6 of these pedestals, you would have 30 receptacles and a permitted demand factor of 70%.
If you are working on a design, pay attention to the Informational Note at the top of the table.

(Table 555.12 in the 2017 code became Table 555.6 in the 2020 code and Table 220.120 in the 2023 code. )
 
Yes, I think its hard to say that the receptacles are dedicated to a single boat slip.

And Note #1 says you can disregard receptacles with different voltages, not receptacles with different currents. (Although maybe the intent was something different.)

So I think you have to count all the 50A receptacles and the 100A receptacle.

That leads me to the same answer Don had.
 
Thanks guys. I didn't realize the code changed. Im on the NEC 2017 but I bought the PDF but I have a bad habit of using by 14'
paper book.

I did some looking into this and apparently the reason why there are (2) 50A + (1) 100A is because some larger boats use a single 100A, and some use (2) 50As (probably with an adapter). The (2) 50A and 100A wouldn't be used at the same time though.

This article really could use a re-visiting. After looking into this for this project, and then reviewing other similar projects, theres a tremendous amount of confusion and disagreement.
 
Npstewart said:
Thanks guys. I didn't realize the code changed. Im on the NEC 2017 but I bought the PDF but I have a bad habit of using by 14'
paper book.

I did some looking into this and apparently the reason why there are (2) 50A + (1) 100A is because some larger boats use a single 100A, and some use (2) 50As (probably with an adapter). The (2) 50A and 100A wouldn't be used at the same time though.

This article really could use a re-visiting. After looking into this for this project, and then reviewing other similar projects, theres a tremendous amount of confusion and disagreement.
Click to expand...
You have an opportunity to work on that. The system is open for the submission of Public Inputs to make changes for the 2026 code.
 
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