Appendix A: Power Options; Poe Power Budget Calculations - Schlage RC Pure IP User Manual

Appendix A: Power options

PoE Power Budget Calculations

When planning an installation using PoE, you need to validate that the PoE source (PoE Injector or PoE equipped Network
Switch) supplying the PoE power is sized properly for all the attached PoE devices. To do this, you total up the power draw (in
watts) of the PoE connections, and compare that total power draw to the rated capacity of the PoE source.
When the Reader Controller is dual powered there may be an increased number of power audits. If the 12VDC regulated power
supply voltage fluctuates above 12.1VDC the Reader Controller will transition from the PoE source to the DC power supply,
resulting in an audit.
Likewise when the DC power supply drops below 12.1VDC the Reader Controller will transition from the DC power supply to the
PSE, resulting in another audit.
Table 4.1: Expected PoE power draws of the reader controllers
Door Location Configuration
Reader controller
Reader controller with Electronic Lock (300 mA @ 12V)
Reader controller with Electronic Lock (600 mA @ 12V)
* Ethernet cabling power losses not included. Losses range from being negligible for short Cat5/6
cables, up to about 16% for 100 meter Cat5/6 cables.
To meet the Reader Controller's variable PoE power requirements, the Reader Controller will classify itself with the PoE source
as a "Class 0" PoE device. The power usage of a Class 0 device can range between 0.4 to 13.0 watts at the device (up to 15.4
watts from the PoE source).
Some network PoE equipment will budget and allocate it's distribution of PoE power based upon the maximum power usage of
the each attached device's classification. If your network equipment uses this power provisioning technique, then you should
budget 15.4 watts for each Reader Controller. Such network PoE Equipment may allow you to manually configure the amount of
power that should be allocated to each device. Configuring the PoE equipment for an allocation of 3.0 watts or 11.0 watts per
connection would be appropriate. When powering from PoE or PoE+, in order for the system to be UL294 V7 compliant, the PoE
injector or end point must be compliant to UL294 or UL294B standards.
Using PoE over longer cable distances:
The Reader Controller can be powered via PoE on cable runs up to 328' (100 m) long (the standard Ethernet cable limit).
For Reader Controller locations that have longer cable runs (> 164' [50 m]), extra care should be given to the planning and
installation of the network cabling. The PoE power delivery system will running at about 80% of the allowable capacity, when
powering a 600mA lock over a 100 meter cable run.
For these long cable run installations, here are some items to focus on:
• Cabling:
• Use high-quality Ethernet cabling (Cat 5e or Cat6). Please note that the power loss over a Cat 6 cable is about 30%
less than the power loss on a Cat5e cable
• Cable Length. The 100 meter limit needs to include any patch cords and patch panels.
• Follow IEEE/TIA installation best practices.
• PoE Source
• The PoE Source (PoE Network switch or PoE Injector) meets the IEEE 802.3af standard.
• The PoE Source is properly sized to supply 15.4 watts/port. (Cabling power loses can be up to 2.5 watts/cable)
16 • Schlage • Reader controller
PoE Power Requirement *
2.65 W
6.26 W
9.85 W