Voltage drop on 1500 feet

[kwired]

You can also purchase 240V rated heaters with a higher wattage rating then needed, then operate at 120V with the calculated voltage drop to give you the wattage you want.

I don't see that solving any voltage drop issues. If you need 300 watts of heat you will still need 2.5 amps of current if the voltage remains the same. Extending the life of the element is about the only benefit of operating it at a lower voltage than it is rated for.

 

[ggunn]

One thing you have going is we calculated assuming all the heaters are on at the same time. That probably will not be the case.

Even if that were the case, good design dictates that you engineer the system to be able to handle them all being on simultaneously.

 

[Open Neutral]

These are 120 volt water heaters for horse farm

{much discussion}
I'd still be asking about 240V heaters instead....and finding a small stepup xfmr.

 

[bob]

Even if that were the case, good design dictates that you engineer the system to be able to handle them all being on simultaneously.

GG
I agree with you 100% but the OP said he only had 120 volts available. My design was based on 240 volts and it works. What can you do if the OP says
that 240 volts is not available? He could install a 120 to 240 volt transformer.

 

[Hv&Lv]

Same size as me, Thanks.
I had a little more drop, but those off shoots kinda messed me up I think.
You da man

For water heaters, why would you care if the VD is more than 5%? What would be so bad if it were 10%, or 15%? Aren't these resistance heaters? What are the chances they will come on all at once? Wouldn't any inconvenience cost much less than the extra conductor?

 

[kwired]

For water heaters, why would you care if the VD is more than 5%? What would be so bad if it were 10%, or 15%? Aren't these resistance heaters? What are the chances they will come on all at once? Wouldn't any inconvenience cost much less than the extra conductor?

The water heaters the OP is talking about are small tank heaters that keep the drinking water for livestock from freezing in the tank, as well as the plumbing that supplies them. Twice now it has been asked what the chances are they will come on all at once. They will run pretty much continuous when it is cold enough outside. They are usually only 300 watts or so, some larger units will have multiple elements. True that excess voltage drop typically not hurt anything but will result in a little less heat, only on the coldest of days that may be an issue, but the thing will not freeze up but may get a thin layer of ice on the top - usually because of severe wind chills more so than just cold alone.

 

[KnobnTube]

Thanks for all input from everyone. Helped greatly.
Customer is evaluating 2 runs and splitting load but still
long run and the possible 240 v with quad cable.

 

[kwired]

Thanks for all input from everyone. Helped greatly.
Customer is evaluating 2 runs and splitting load but still
long run and the possible 240 v with quad cable.

Let me guess he is balking at cost. Tell him they do make propane heaters for livestock watering units also. But then he will need multiple tanks or run a lot of gas line, and it is not always easy to get a tanker truck out there to refill the gas tanks.

The electric lines are usually buried in same trench when the water line is buried, if so he is not paying for twice the trenching.