GE VersaPoint IC220PBI002, Руководство пользователя

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C-4 VersaPoint™ I/O System Profibus-DP NIU User’s Manual – August 2005 GFK-1911B
C
Permissible Operating Temperature Range
With an increased ambient temperature, you must calculate the permissible
operating temperature range for the calculated power loss.
Set P
tot
= P
HOU
.
P
tot
= 2.4W - [(T
U
+ 5°C) / 37.5K/W]
After changing the formula, the maximum permissible ambient temperature
is calculated with this load as:
T
U
= (2.4W - P
tot
) x 37.5K/W - 5°C
P
tot
= 1.38W (from the calculated power loss of the electronics)
T
U
= (2.4W - 1.38W) x 37.5K/W - 5°C
T
U
= 1.02W x 37.5K/W - 5°C
T
U
= 33.25°C
With full load on both outputs, you can operate this module up to an ambient
temperature of 33°C (91.4°F). If you never operate the outputs
simultaneously and if a set output consumes a current of 2A you can
operate the module up to:
P
tot
= 0.18W + 1 x [0.20W + (2A)
2
x 0.1 Ω )]
P
tot
= 0.18W + 0.60W
P
tot
= 0.78W
T
U
= (2.4W - P
tot
) x 37.5K/W - 5°C
P
tot
= 0.78 W (from the calculated power loss of the electronics)
T
U
= (2.4W - 0.78W) x 37.5K/W - 5°C
T
U
= 1.62W x 37.5K/W - 5°C
T
U
= 55.75°C
T
U
= 55°C (maximum permissible ambient temperature)
As the maximum permissible ambient temperature is 55°C (131°F) you can
work in the entire permissible temperature range under the above
mentioned conditions. This leads to a simultaneity of 50% at 55°C indicated
in the data sheet.