long feeders & voltage drops

Status
Not open for further replies.
gar said:
110312-1901 EST

iwire and hurk:

I believe you have misunderstood what I was trying to say.

In todays time I believe the nominal unloaded design goal for power system voltage at the destination is 120 V. This in turn means that equipment designed to operate on this system would have nominal voltage design criteria of 120 V, or maybe offset a little.
.
Click to expand...

ANSIC841.jpg


I think the above is generally accepted.

In the areas that require compensating for voltage drop the requirements are often part of energy savings codes. That being the case you would have to upsize the conductors to reduce the losses.
 
Using buck boost or re-tapping a transformer to over come a voltage drop on a circuit...
Click to expand...
While perhaps not feasible in the OP's case, transformers with LTC and automatic tap changer controls can be used to compensate for voltage drop with dynamic loads. This tap changer control has a Line Drop Compensator with settings for resistive and reactive components related to line loss in order to provide a set voltage down the line from the transformer:

http://www.beckwithelectric.com/products/m-2001d.html
 
110312-2159 EST

iwire:

That is a useful table.

I would like clarification on the meaning of the columns.

My assumptions would be:

Service --- no load voltage nominal design.
Utilization --- full load at the load, but then why would the high value be greater than the service high end? Maybe that allows for shunt capacitor effects.
Nameplate --- makes sense to put it in the middle of the Utilization range. Also i would assume full mechanical load.
NEMA --- again makes sense for full load and the Utilization range.

Can you verify if my assumptions are correct or not?

.
 
Utilization is the same as premises.

Wow 208-254 I never really thought of it this way but sure makes sence to not overstate the 3% VD (not NEC required anyway)
 
Status
Not open for further replies.
Top