IP Based Building Networks
EN 50173-6 for distributed building services
More and more building technology applications come with an IP port: Video surveillance, access control, time recording, lighting, heating, ventilation, air conditioning, blinds, WiFi, cordless telephone and smart phones (DAS), sensor networks, ... the list grows nearly every day. EN 50173-6 specifies the appropriate cabling for this.
WiFi access points are not the only IP devices that can be installed in ceilings. LED lighting fixtures and their controllers, temperature and light sensors, presence detectors – all of them with Ethernet ports – can be placed there, which led to the term „digital ceiling“. As the devices as well as their cabling can be installed very easily in drop ceilings, digital ceilings play an important role in smart buildings. A universal cabling for any application allows easy and cost-effective changes of devices.
Using patch cord and outlets to connect devices to the network is not always the best solution. Patch cord and outlets for cameras in high-security areas or WiFi access points in a lobby do not please the eye at best and can become a security risk at worst. Field-installable RJ45 plugs that are mounted directly on the horizontal cable eliminate the need for outlets and patch cords. What has to be minded, however, is that such end-to-end links or „modular plug terminated links (MPTLs)“ have to be tested using the appropriate test adapters. Channel test adapters won‘t do the job as they disregard the first and the last connector in a link.
Single Pair Ethernet (SPE)
Not all devices need four pairs to be connected to the network. Single Pair Ethernet (SPE), which uses just one twisted pair of wires, can be a very interesting alternative, saving space and money. The objectives of SPE are to deliver data rates of 10 Mbps, 100 Mbps and 1 Gbps. Standardization is not finalized yet. Variants are or will be standardized in:
IEEE 802.3cg (10 Mbit/s)
IEEE 802.3bw (100 Mbit/s)
IEEE 802.3bp (1 Gbit/s)
IEEE 802.3ch (2,5, 5 und 10 Gbit/s)
The link lengths depending on the data rate are 15 m, 40 m and 1000 m; some variants should be able to offer up to ten connections in a link.
Power over Data Lines (PoDL)
SPE allows the remote powering of devices via the horizontal cable, eliminating the need of an additional electrical socket. This can come in very handy especially for very small devices like sensors and actuators. The technology for this is quite similar to the familiar Power over Ethernet (PoE), but they are not compatible as PoE needs a minimum of two wire pairs. In order to avoid any confusion, a new name has been created for the new remote powering over just one wire pair: Power over Data Lines (PoDL).
PoDL is standardized in IEEE 802.3bu. During normal operation, devices can use up to 50 W drawing 1360 mA.