Use of Power over Ethernet at the UZH

In general, the newer Ethernet switches have the function Pover over Ethernet (PoE). Using PoE, power can be supplied to certain end devices via the Ethernet switch instead of via a small power supply unit at the end device, which has advantages in terms of energy efficiency and operation. This means that in the IP telephones alone, there is no need for approx. 10,000 small individual power supply units.

Power supply via PoE has been designed and planned for the following centrally managed devices:

• IIP telephones (responsibility: Central IT, IT Infrastructure Department)
• WLAN transmitter (responsibility: Central IT, IT Infrastructure Department)
• Lecture hall cameras (responsibility: Central IT, MELS Department)
• Security cameras (Responsibility: Security and Environment)
• Temperature sensors (responsibility: engineering and equipment/Central IT)

Further applications for central services, e.g. in the areas of building management or security, are possible in principle. The modalities must be agreed upon in advance with the Central IT, IT Infrastructure Division.

PoE is not available for individual applications. The use of third-party devices can endanger the operation and is prohibited. Unauthorized PoE users are detected and switched off by the network management system.

The PoE supply voltage is always available at the UKV connection box. It is forbidden and dangerous to connect a device to a UKV socket which in turn carries a supply voltage at the Ethernet interface! The coincidence of the two power supplies can lead to network disturbances or hardware damage both to the connected device and to the central switch. Hardware damage to the central switch leads to power failures and high repair costs.

Especially when using mini-switches with PoE ports (not recommended), it is therefore essential to ensure that only a switch port without PoE is connected to the UPS junction box!

If you have any questions, please contact the staff unit "Coordination IT and Construction" of the IT Infrastructure Department of the Central IT. Contact: itundbau@zi.uzh.ch.