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<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2>48VDC is a long time telco standard - and has become the
Power over Ethernet standard.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2>Keep in mind that 'electricity' isn't the measure - it's
power. Power is not synonymous with voltage.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2>The formula V=IR (voltage equals current time resistance)
points to a higher voltage allowing lower current draw on the line (with the
same resistance). Think of the small gauge wires in CAT 5 cable; higher
voltage allows the thin cables. This has nothing to do with voice
quality.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=137062304-23112006><FONT face=Arial
color=#0000ff size=2>MD</FONT></SPAN><BR></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
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<FONT face=Tahoma size=2><B>From:</B> asterisk-users-bounces@lists.digium.com
[mailto:asterisk-users-bounces@lists.digium.com] <B>On Behalf Of </B>Zeeshan
Zakaria<BR><B>Sent:</B> Wednesday, November 22, 2006 9:30 PM<BR><B>To:</B>
Asterisk Users Mailing List - Non-Commercial Discussion<BR><B>Subject:</B> Re:
[asterisk-users] Why Aastra uses 48V whereas other IP Phones usemuch less, i.e.
5-12V<BR></FONT><BR></DIV>
<DIV></DIV>Does it effect the performance/voice quality? Does this also mean
that 48VDC is using less electricity in an office than 5VDC IP
Phones?<BR></BODY></HTML>