Voltage Drop, Marinas (practical or dangerous)

[iwire]

My comment is that we need code compliance, stating that over 3% voktage drop cannot be permitted,

Hector the NEC has no requirement to limit voltage drop. It is strictly a design decision unless there are local codes that have voltage drop restrictions.

 

[charlie b]

. . . we need code compliance, stating that over 3% voltage drop cannot be permitted. . . .

The 3% value is not a code requirement. It shows up only in the unenforceable "Fine Print Notes."

 

[hector pe]

Voltage Drop-NEC

Voltage Drop-NEC

Gentlemen:

I understand and appreciate your points of views. It can be interpreted as unforceable or it is not a requirement. However, based on my experience in the power distribution design I try to follow the Nec codes, standards, recommended practices and guides to protect life and property.
In some US states and territories, NEC is part of other Building Codes that are enforced by law.

 

[charlie b]

Hector, you misunderstand us. We also follow the NEC and all other applicable laws. Yes indeed, we know that the NEC is law. We too are concerned with the health and safety of the public. Some members of this Forum are going to take unkindly any suggestion that we have no concerns for public safety, or that we are willing to violate the law. I am among them. So on their behalf, let me ask you to reconsider the way you worded your comment.

What we had tried to convey is that the NEC itself does not require that we keep voltage drop below 3% or 5%. The 3% limit is not law. The NEC merely suggests that those limits are good ideas.

 

[hardworkingstiff]

Lou,

It can be a fine line between a good marina and a bad one.

AMEN! (looking for that line, lol).

I have used the 80% amp rating at 240 volt of the receptacle/breaker to help reduce the costs for the install, especially with the price of W-cable. Also are you using the demand factors and KWH meter 10% credit? These help reduce the cable costs.

The meter demand factor really only helps on the service size. When pedestals are rated for 100-amps (50 side A and 50 side B) or 200-amps then usually there is a home run to each pedestal.

For the voltage in your example to have gotten down below 200-volts tells me that not much consideration at all was given to VD in the original installation.

The way I see this problem is we really don't know what the load is. In a perfect world, we just spend whatever it takes to keep the VD less than 3% calulated at the maximum possible load. Well,..... the world is not perfect and although marinas are money makers, the owners don't want to give it all to the wire manufacturer (or the electrician either). I'm just looking for thoughts of others on this subject.

I thank everyone who took the time to type their input.