Global Power Technologies
1120 - Class I, Division 2, Group D, T3
The relationship between V
set
and power (P) is:
P = V
set
2
0.387
This relationship is shown in Figure 12. The graph gives V
set
as a function of set-up power. In
determining power (P) consider the following example:
1)
Your V
set
is 6.12 volts.
2)
Locate 6.12 volts on the vertical axis.
3)
Read horizontally until intersecting the curve.
4)
Read vertically downward to the horizontal axis to determine power
w
hich is 97 watts.
In determining V
set
consider the following:
1)
The power is 120 watts.
2)
Locate 120 watts on the horizontal axis.
3)
Read vertically until intersecting the curve.
4)
Read horizontally to the vertical axis to determine V
set
Which is 6.8
volts.
2 .7 Determining Required V
set
This heat up period is the ideal time to determine the V
set
. V
set
is based on set up power as
follows:
SET UP POWER from Figure 4
V
set
from Figure 12
Set up power is found by adjusting the desired power for ambient temperature. V
set
is deter-
mined from set up power as shown in Figure 12.
1)
Estimate the maximum ambient temperature expected at the side and record on the start
up data sheet as Item 3.
2)
Measure or estimate the present ambient temperature and record as Item 4.
If rated power or maximum allowable power is desired:
3)
Use the information in Figure 4 and the procedures in section 1.7 to determine the cor-
responding set up power and record as Item 5.
4)
Use Figure 12 to determine the related V
set
and record as Item 6.
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