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3 years ago

How dose north america achieve 480VAC with 3 pole 120VAC

Mathematics

1 answer:

makvit [3.9K]3 years ago

7 0

Answer:

There are a variety of factors driving the

adoption of 415/240VAC distribution. First,

distributing at these increased voltages

enables overall efficiency to be enhanced

by eliminating the need for a voltage

transformation along the power path. For

example, in a 415V system, the L-N voltage

is 240V, which is compatible with most all IT

loads. By shifting the UPS output distribution

voltage to 415/240 V three-phase (L-L/

L-N), most of the existing servers today can

be powered with 240V single-phase (L-N)

without any intermediate transformation.

Removing the need for a transformer

streamlines the power path and can increase

efficiency approximately 1.5 percent.

The adoption of a 415/240VAC distribution

model also can yield additional savings at

the device-level in the form of increased

efficiency for server power supplies. As

previously mentioned, today’s power

supplies can handle a wide range of incoming

voltages. Based on the actual voltage being

fed into the power supply, efficiencies can

range from as low as 80 percent (at 100V

nominal) to as much as 94 percent (at 240V

nominal) across all manufacturers.

Furthermore, while the typical efficiency

differential between 240V and 208V gained

at the server power supply today is a relatively

minimal, only 0.3 percent across most of

the load range, the efficiency differential

between 240V and 120V servers can be as

much as 2 percent for a given power supply.

It is this value that often gets overstated by

some manufacturers when comparing 415V

distribution to “traditional methods,” as

there are relatively few servers or peripherals

installed today that are operating at 120V.

Step-by-step explanation:

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6(7) = 7y
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3 years ago

In a murder investigation, the temperature of a corpse was 32.5 degrees C at 1:30 pm and 30.3 degrees C an hour later. Normal bo

svp [43]

Let $T(t)$ be the temperature of the body $t$ hours after 1:30 PM. Then $T(0) = 32.5$ and $T(1) = 30.3$ .

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$

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3 years ago

Which of the following are equations for the line shown below? Check all that

Maurinko [17]

ANSWER: A & B

FOR COORDINATES (2,2)
A) 2-2=-0.25(2-2)
0=0
B) 2-3=-0.25(2+2)
-1=-1

FOR COORDINATES (-2,3)
A) 3-2=-0.25(-2-2)
1=1
B) 3-3=-0.25(-2+2)
0=0

WHY ITS NOT C and D

COORDINATES (2,2)
C) 2+3=-0.25(2-2)
5=0 ZERO DOES NOT EQUAL 5
D) 2-3=-0.25(2-2)
-1=0 ZERO DOES NOT EQUAL -1

COORDINATES (-2,3)
C) 3+3=-0.25(-2-2)
6=1 SIX DOES NOT EQUAL 1
D) 3-3=-0.25(-2-2)
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2 years ago

E + 1 = 4f<br> Pls help me

pochemuha

Answer:

E= 4f - 1 f= e+1/4

Step-by-step explanation:

5 0

3 years ago