Transition Networks
SISTP1040-382B-LRT Install Guide
33806 Rev. B
Page 28 of 39
Typical PD Power Requirements
□
1.8 Watts: Transition Networks’ M/GE
-ISW-SFP-01-PD (Class 1 Powered Device (0.44 Watts - 3.84 Watts).
□
13W: IP Camera, VoIP Phone, Wireless Access Point, Networked Audio.
□
30W: IP Telephone, WiMAX Access Point, PTZ Camera, Remote Computer Terminal.
□
60W : Door Access System, Video Phone, Thin Client.
□
100W: Digital Signage Display, Point-of-Sale System, LCD TV, Computer Monitor.
□
200W: Larger TV, Larger Display, Larger Monitor, Laptop.
After eliminating basic network
factors, ask your PD vendor for the PD’s power supply mode and polarities
supported and exact power consumption.
Calculate PoE Power Budget
To calculate how many 802.3at devices the unit supports, divide the Total PoE Budget (130 Watts) by 30 Watts.
To calculate the maximum number of 802.3af devices, divide the Total PoE Budget (130 Watts) by 15.4 Watts.
VoIP vs SIP
VoIP (Voice over IP) involves making or receiving phone calls over the Internet or internal networks.
SIP (Session Initiation Protocol) is an application layer protocol used to establish, modify, and terminate
multimedia sessions such as VoIP calls. One difference is their scope. VoIP is not a discrete technology; it is a set
of technologies used in modern telecom networks. SIP is a signaling protocol used within VoIP technology.
Another difference is that VoIP sends only voice messages, while SIP can carry all media forms (not just voice
messages).
Mixing POE and Non-POE Devices
You can mix POE and non-POE devices on the same POE switch (i.e., you can put PCs on the same POE switch as a
SIP phone or a VOIP phone). The PSE (your switch) will only send power if requested by the PD.
Ethernet and PoE Intra-Building Cabling Warnings
1.
Ethernet cables are intended for intrabuilding use only. Connecting your TN switch directly to Ethernet
cables that run outside the building in which the switch is housed will void the user's warranty and could
create a fire or shock hazard.
2.
PoE cables are intended for intrabuilding use only. Connecting your TN switch directly to PoE cables that
run outside the building in which the switch is housed will void the user's warranty and could create a fire
or shock hazard.
3.
For outdoor PoE applications, we recommend using Transition Networks' SI-IES-1200-LRT Unmanaged
Hardened PoE+ Injector or SI-IES-111D-LRT Unmanaged Hardened PoE+ Injector/Converter Use of any
other PoE injector will void the user's warranty and could create a fire or shock hazard.
Legacy PD Detection / Capacitor Detection
Legacy PDs refers to powered devices manufactured before the IEEE standard was finalized and do not have the
expected PD signature required by the PSE's detection signal. Such PDs usually feature large capacitance as the
detection signature that does not completely comply with the 802.3af specs. By enabling this option, the switch
will probe for legacy PDs and if a legacy PD is detected, the switch will provide power to the PD.
