230 volts vs. 480volts

[zipthetrip]

Can someone please answer a few questions regarding volts and amps. First of all, I have 6 air compressors, all running off of 230v 3ph. I know I am close to blowing the box off the wall. If I convert to 480v 3ph, this will decrease my amps used by about half right? Second question, by converting to a higher voltage will I be saving $$$ on the electric bill? If so, at what percentage? Finally, what is the benefit of stepping up the voltage?

 

[LionelHutz]

Yes, doubling the voltage will half the current.

No, you won't save any significant amount on your electric bill. There are some I^2*R (or power) losses that are saved by reducing the current, but it's minimal compared to the power the motor uses running it's load.

The benefit of higher voltage is using smaller conductors to supply the same amount of power. If you half the current then you only need conductors and switches and fuses and contactors that handle half the current which saves installation costs.

 

[briand2]

You will need to ensure that all your equipment, cables, etc can handle the increased voltage. You will also need to ensure that your electricians, etc treat the increased voltage with the respect it deserves!

 

[itsmoked]

Not usually worth it in an existing installation.

 

[jraef]

I agree, not worth it since your wires are already there, and as mentioned, it may require changing out some of your equipment such as switches etc. In addition, you would need to make sure your motors can be connected at 460V as well. Most 230V motors built in the last 20 years are, but it is not a certainty.

And LionelHutz is correct, no energy savings worth discussing. Energy is billed in kWh (kilo Watt hours). The main part of the formula for that is kVA, or Volts x Amps / 1000. If the Volts are doubled, the Amps are cut in half, but the kVA is identical.


"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more." Nikola Tesla
Read the Eng-Tips Site Policies at faq731-376
Member, [blue]P³[/blue]

 

[BigWallyB]

After all the aforementioned caveats. If your facility is growing, then it may be a worthwhile exercise after all. It would in affect double the current-carrying ability of your present wiring so as to reduce or eliminate the need to run new stuff. Then savings could be more substantial.

Life is what happens while we're making other plans.

Wally

 

[zipthetrip]

Thank you all for taking the time to answer this thread. Your help in this matter, and the information I have recieved has been priceless. A real time saver. I love this site!

 

[stevenal]

A utility I know has chosen to implement power factor penalties only at 480V and higher. Customers who convert are sometimes surprised to see the bills go up.

 

[jraef]

Oh now that's a new twist! LOL, any way to sneak in a few extra billables I guess.

 

[k2panman]

First things I'd check before considering converting are:
1) are the motors on the compressors capable of being fed at 480V? If not, motors are pretty expensive to change out.
2) Is 480V service available at the site? If not, bringing iin 480V may be expensive. The utility company may not have 480V service there, which will require installing additional transformers at the site.

K2ofKeyLargo