Positron Teleline 751109/15, Описание и установка

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Temperature Considerations
2. Add the power consumption of all cards powered by -24 Vdc. This value
represents the “Total Power Consumption” at -24 Vdc. This value is required
for the calculation of the power dissipation of the internal power supply.
3. Add the power consumption of all cards powered by -48 Vdc. This value
represents the “Total Power Consumption” at -48 Vdc. This value is required
for the calculation of the power dissipation of the internal power supply.
4. Add the power dissipation of all cards. This value represents the “Total Power
Dissipation.”
5. The “Maximum Operating Temperature” of a card represents the highest
temperature at which a card is guaranteed to operate within specifications. At
the bottom of the maximum operating temperature column, enter the lowest of
the maximum operating temperatures. This temperature is referred to as the
“Highest Allowable Temperature.”
6. The temperature inside the shelf is calculated using the following equation.
7. Temperature inside the shelf = (Total Power Dissipation x Shelf Thermal
Resistance) + Room Temperature
8. Shelf Thermal Resistance = 0.31° C/W (0.56°F/W)
9. Compare the “Calculated temperature inside the shelf” with the “Highest
Allowable Temperature.” The “Temperature inside the shelf” should not
exceed the “Highest Allowable Temperature.”
If the calculated temperature is higher than the highest allowable
temperature, the following can be done:
³ To lower the temperature inside the cabinet:
1. Reduce the number of cards in the shelf by distributing the cards among other
available shelves.
2. Move the cards between shelves to replace a card that dissipates heat with
one that does not, for example, model 7501-24.
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If an external power supply is being used, omit this step.
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If an external power supply is being used, omit this step.