PoEp minimum voltage
Let us look on this issue under another angle assume minimum load need to be delivered to PD by four pair is 40W
Power dissipation on a cables for 51V PSE will be 2.45W less then for 44V
Advantages of higher voltage is increase with increasing power level
| 44V | 51V |
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Pd power | 40W | 40W |
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Current per pair | 0.54A | 0.44A |
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Power dissipation | 7.3W | 4.85W |
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on a cables (4P) |
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PSE power | 47.52W | 44.88W |
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System efficiency | 0.84 | 0.89 |
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for ~500W PSE PS |
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www.PowerDsine.com |
| PowerDsine Presentation October 2005 Page 6 | |