[SBE] A/C 3phase vs single phase

[Andy Butler]

If you can start from scratch - set your facility up with 3 phase 480
service - you will save substantial money running your lighting and
other peripherals on 277 volts and your HVAC/Elevator/fire pump/antenna
de-icers/Large Scale UPS systems are a lot less expensive if you can run
them at 480 volts.

You will have to use step-down transformers for wall outlets and rack
power.  One trick - if you can afford a full facility UPS system for
Technical Power buy the unit to use 480/ 3 phase in and 208/220 out.

By the way - when you talk to the Utility Company - make sure you get
past the "consumer" screeners and talk directly to the people who handle
industrial accounts.  Generally speaking the utility company is more
than happy to supply 480 volt/3 phase or higher - I've had a couple of
plants that used 13 Kv directly from the pole...now that can save some
serious money! 

-----Original Message-----
From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org] On Behalf Of Bob
Reite
Sent: Thursday, June 11, 2009 9:46 AM
To: sbe member discussion mail list
Subject: Re: [SBE] A/C 3phase vs single phase

Unless you already have 3 phase service in the building, it's probably 
not worth the extra expense to have it installed.

Chris Hoopes wrote:

> It comes up every now and then that I am called upon to scope out new 

> air conditioning systems. I always figured with both available, that 3



> phase was more efficient. Less current is required to start a 3 phase 

> motor. Smaller gauge wires, but more of them. But then the other day I



> was called down on this. I wondered if advancement in A/C technology

had 

> changed the fact. The way 3 phase is measured is a difficult concept, 

> peak demand. What has been your experience? Is 3 phase cheaper to 

> operate and cool with then a 2 phase system? Or is there no

difference?

> 

> 

> 

>

------------------------------------------------------------------------

> 

> _______________________________________________

> The SBE Roundtable, SBE at sbe.org

> To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

> 

> http://seven.pairlist.net/mailman/listinfo/sbe

_______________________________________________
The SBE Roundtable, SBE at sbe.org
To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

http://seven.pairlist.net/mailman/listinfo/sbe


The national DTV Deadline is June 12th.
Help make sure your friends and family are ready.  
Find DTV how-to tips at pbs.org/dtv 
_____________________________________________________________________________

This email may contain material that is confidential or proprietary to PBS and is intended solely for use by the intended recipient. Any review, reliance or distribution of such material by others, or forwarding of such material without express permission, is strictly prohibited. If you are not the intended recipient, please notify the sender and destroy all copies.
_____________________________________________________________________________