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Rev. 1.0.1 | © 2018 Dallmeier | www.dallmeier.com
MDF5400HD-DN Commissioning
If you operate the device with Power over Ethernet (PoE), observe the following notes:
NOTICE
Damage to the contacts of the RJ45 connectors by contact erosion when un-mating the jack-plug connection under PoE load
Un-mating the jack-plug connection while transmitting PoE power causes erosion and pitting by electrical arcs on both the jack and plug
contacts (especially when repeatedly un-mating the jack-plug connection under PoE load).
Electrical arcs are generated, since the electric potential difference (voltage) and therefore the intensity of the electric field between the
contacts rises sharply when un-mating the jack-plug connection.
The more un-mating cycles are carried out under PoE load, the higher the loss of contact material due to metal evaporation by electrical
arcs, which in turn accelerates the material erosion process on the contact surfaces.
Damaged contacts with an increased contact resistance may lead to a reduced data transfer rate, unreliable network connectivity or even
total device failure.
➡
Always disable PoE on the relevant port of your PoE switch (or PoE midspan device) or disconnect the used single-port PoE injector
from the power supply before un-mating the jack-plug connection in order to prevent damage to the contacts of the RJ45 connectors
by contact erosion.
