dallmeier DDZ5200HD Series, Manual

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COMMISSIONING – DDZ5200HD Outdoor Series | REV. 1.0.0 | © 2021 Dallmeier
Power over Ethernet (PoE+)
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.