Positron Teleline 751960/13CU5, Description And Installation Manual

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Teleline HVI Single 5-card Shelf Cabinet, model 751960/13CU5
4.2 Thermal Calculations
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Calculating the temperature inside the HVI Cabinet
1- Add the power dissipation of all the NIU cards inside the Hyperedge shelf at 4W
per NIU card (maximum of four cards).
2- Divide the resulting power by 0.89 to account for the efficiency of the power
supply. The resulting power is the power dissipated inside the cabinet (but not the
shelf).
3- From Table 16, calculate the sum of the power consumption (2nd column) of all
the cards in the Teleline shelf.
4- If there is a plug-in power supply inside the shelf, divide the power consumption
obtained in step 3 by 4 to get the power dissipated by the power supply.
5- From Table 16, calculate the sum of the power dissipation (3rd column) of all
the cards in the Teleline shelf plus the power calculated at step 4. That is the total
power dissipated in the shelf.
6- Multiply the power calculated at step 2 by 0.11ºF/W (0.06ºC/W).
7- Multiply the power calculated at step 5 by 0.072ºF/W (0.04ºC/W).
8- The sum of both numbers obtained at step 6 and 7 gives the temperature rise
inside the cabinet. Add this number to the ambient temperature to get the
temperature inside the cabinet.
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Calculating the temperature inside the Teleline shelf
9- Multiply the power calculated at step 5 by 1.26ºF/W (0.7ºC/W).
10- The sum of the numbers obtained at step 8 and 9 will give the
temperature rise inside the Teleline shelf. Add this number to the ambient
temperature to get the temperature inside the Teleline shelf.