O'Reilly logo

Power Over Ethernet Interoperability Guide by Sanjaya Maniktala

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Protecting the PD from Surges
In a very similar manner, we can test the PD for surges too. The logic is the same actually, because looking in from the cable, the PD looks (coincidentally) very similar to the the PSE. We “see” a bunch of Y-caps, a port cap of 0.1 μF, a TVS, and also a bulk cap—the latter being the input cap of the DC-DC converter that follows. See Fig. 11.11. Just as in the case of a PSE wired in DC disconnect.
image
image
FIGURE 11.11   Surge test on a PD.
This leads to an equivalent circuit akin to a PSE with DC disconnect as in

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required