Newer APs often come with some pretty hefty power requirements. Standards such as the 15.4W 802.3af specification are increasingly insufficient on APs that are more power hungry. Enter the 802.3at standard that can support all the way up to 30.0W! While runtime operation of these (over PoE switches) is a topic all of itself, the Wi-Fi professional has always had issues with doing AP on a Stick designs (site surveys, empirical measurements) – especially when your AP power requirements exceed some of the more tried and true solutions. I’ve hashed out several different solutions over the past year, and thought it was time to write them all down.
The staple of AP powering has been for a very long time the Ventev / TerraWave – MIMO Site Survey Battery Pack. On its own, it only supports the older 802.3af specification. This all in one solution is portable, but since it’s based on old lead-acid technologies, it tends to fall on the heavier side of the solutions. Venerable, heavy, doesn’t support newer APs, but everyone has them.
The Terrawave Site Survey Battery Pack!
Enter the Tycon Systems DC To DC Converter And POE Inserter. This bad boy becomes an integral part of most of the rest of our solutions – and it’s very important to understand that it comes in a variety of input voltages. You must mate it to the power solution you’re using.
The Tycon POE injector.
Using the Ventev MIMO Site Survey Battery pack, you can see from it’s data sheet that it supports an external 56V output. If you use the included 56V cable, cut the ends off and mate that with the Tycon that has 802.3at power output, you can retrofit existing site survey battery packs to support newer high power APs! Sadly, physics wins out at some point. Since you’re drawing more power, invariably your battery will not last as long. If you have an older unit, you may be having problems holding a charge or any other number of other issues, but if you’re in a bind, it’s a potential solution.
If you think this Tycon solution looks familiar, Scott Stapleton wrote about a similar solution in his blog. Using the injector that he stated (TP-DCDC-1248GD-HP, note the 10 to 15VDC input change), along with commonly available batteries such as the RAV power units, you can extend the run time of your APoS efforts by interchanging either larger capacity batteries or additional units. In my tests, I used two of the RAVPower 2300mAh batteries along with the Jacobs interconnect to complete the solution.
Image shamelessly stolen from Scott Stapleton.
Thanks to Keith Parsons for this next solution, which is a variation on Scott’s using a battery from Hardened Power Systems. The ReVolt G2 is a large capacity battery that uses 12V powerpole connectors that is *very* light (27 ounces) due to the LiFePO4 battery technology. This, mated with correct Tycon solution using the 12V powerpole connectors gives you a far more portable solution (one high capacity battery, one injector) that can last all day long!
High Capacity Battery, lightweight.
While these all address in varying ways different requirements, they’re all considered a touch on the bulky side and carrying around multiple pieces has always been a challenge for a road warrior that doesn’t want to lose or break bits and pieces. Enter the Ventev VenVolt solution that they were showing off at Cisco Live US 2017. While this isn’t shipping yet, they had a prototype to show off that looked awesome! Lightweight, all in one solution, all day battery on modern technology. Stated dimensions for the unit are 9 3/8″ x 4 3/4″ x 3″ according to Mike Parry. I for one can’t wait for a fully integrated solution to finish baking and come to market!
from
https://sc-wifi.com/2017/07/20/portable-power-for-apos/
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