I was fortunate enough to acquire a pair of Phoenix Contact FL WLAN 2011 radios for my lab. I have been wanting to dig into them for quite some time, and now I had the opportunity!
These are small, dual band 802.11 wireless access points. They can function as a standard wireless access points/gateways, mesh or as wireless bridges. They come in two different versions, one with internal omni/directional antennas and one with external antenna connections. I have a pair of the external antenna units.
The only power option available for these devices is 9 to 32 VDC, so any standard 24v DC industrial power supply should be fine.
Mounting
Their small form factor is designed to be mounted on any surface of the box you are placing them in. Top, side, front or bottom of a panel box are all viable locations for mounting. The internal antenna model is meant to be installed on the exterior of a cabinet. It is IP66 rated for industrial environments once bolted down. The external antenna version is meant for inside a cabinet. There is even an optional din rail mounting kit if you want to keep them in line with other devices for ease power connections.
When using the internal antenna version (the FL WLAN 2101), you need to be aware of the signal propagation. This will allow for better placement depending on the needs of the project.
When looking at these radiation charts, remember that Azimuth (or H-Plane) is looking down over the top of the AP as if you had set it down flat on a table. Elevation (or E-Plane) is looking at the wireless device from the side as if you then knelt to look at the actual side of it as it sat there on the table.
On both 2.4 and 5 GHz, the Azimuth/Horizonal patterns are fairly consistent in 360° coverage. The elevation patterns seem to be a little quirky but are not a deal breaker. Like I have said before, the point is that being familiar with a radios antenna radiation patterns increases the likelihood of a successful deployment.
With the FL WALN 2011 models I was testing with, I used two shorter rubber duck style dual band omni-directional antennas with a low gain of 2db. These were directly attached to the access point.
Connection Capabilities
The FL WLAN 2011/2101 is capable of both 2.4GHz and 5GHz, but not simultaneously. So, while it is in dual band in spirit, it can only broadcast in one single band at any given time. They operate on the 802.11abgn standard with no Bluetooth options.
Wireless security types include the standard fair of WEP through WPA2 PSK and an EAP option. Additionally, there is a section for RADIUS configuration as well.
The flexibility of these radios comes into play by way of the multiple operating modes they are capable of. These modes are:
Access Point – This is standard access point functionality. The software has DCHP services built-in, but its use is optional.
Client (FTB) – This mode is for wireless bridging between Phoenix Contact radios only providing network connectivity for wired devices behind each radio.
Client (SCB) – The mode allows for a single client with no wireless capabilities to be hard lined to a 2011/2101 and then wirelessly bridged to an access point. This mode is compatible with all other manufactures wireless access points.
Client (MCB) – This mode allows for multiple hard lined clients behind a 2011/2101 to be wireless bridged to another network. This mode is compatible with MOST other wireless manufactures, but not all.
MESH – This is a vendor proprietary mesh that only works with other Phoenix Contact radios. This mode was not tested for lack of enough radios for a fully functional evaluation.
So how much bandwidth can be pushed across these multiple modes? I stood a pair of these radios up in my lab on my development network to test this very thing.
***DISCLAIMER***
These tests were performed in my lab which is a controlled setting with low wireless contention and virtually no non-WiFi based interference. Your experiences will vary depending on the environment you install them in.
***END DISCLAIMER***
My bandwidth testing software of choice is jperf. It is essentially the same iperf we all know and love but wrapped in a nice little GUI for ease of use on Microsoft Windows computers.
The tests I performed were:
- Access point mode (802.11n, Max EIRP of 15 dBm)
- 2.4 GHz wireless client to workstation on the development LAN
- 5 GHz wireless client to workstation on the development LAN
- FTB mode (802.11n, Max EIRP of 15 dBm)
- 2.4 GHz wireless bridge connecting hard lined clients on either end
- 5 GHz wireless bridge connecting hard lined clients on either end
- SCB Mode (802.11n, Max EIRP of 15 dBm)
- 2.4 GHz wireless bridge connecting to Phoenix Contact, Cisco and Aruba APs with hard lined clients on either end
- 5 GHz wireless bridge connecting to Phoenix Contact, Cisco and Aruba APs with hard lined clients on either end
- MCB Mode (802.11n, Max EIRP of 15 dBm)
- 2.4 GHz wireless bridge connecting to Phoenix Contact, Cisco and Aruba APs with hard lined clients on either end
- 5 GHz wireless bridge connecting to Phoenix Contact, Cisco and Aruba APs with hard lined clients on either end
The throughput results for 2.4GHz were solid. In 2.4GHz, the average value was 20.63mbps. It is interesting that the average of this value really didn’t change much through the various modes until I got to MCB mode with other vender access points. With these the average dropped about 5mbps. Overall, I feel comfortable in saying that these radios will typically get approximately 20mbps in 2.4GHz across the board.
5GHz performance was also very consistent with one exception. While all of the bridge modes were averaging around 41 or 42mbps, access point mode steadily got results of 74mbps or better.
The persistent results of the throughput tests speak to the quality of these radios. The only real variance being Multi-Client Bridge mode when used with other vendors access points. The only thing I can think of is perhaps it’s the extra overhead the 2011 has to deal with when involving non-Phoenix Contact radios. Maybe I can get an answer from the PXC guys and if so, Ill post an update. The official test results are linked below for each of the tested application types.
FL WLAN 2011/2101 Throughput Test Results
Device Interface
Phoenix Contact has done a great job with the web interface. It is a straightforward design with little fluff. It is easy to navigate and configure. To be honest, the most complicated thing about these was figuring out the mode types and how to test them. Out of the box and having never touched one of these before, it took me about 15 minutes to stand up a single radio in AP mode. Most of that time was figuring out what channel I wanted to use. Once I understood the various bridge modes, config time for those was minimal. Attached below are a few screen grabs of the GUI.
My Thoughts
I really like these radios. Though the 2101 is somewhat limited in applications due to its funky elevation radiation patterns, but the sky is the limit with the 2011’s. When you combine the multiple operational modes with the sheer variety of antenna types that can be used with the 2011, the versatility of deployment possibilities becomes staggering. They could be:
- combined with “Leaky Coax” for assembly lines
- combined with omni-directional antennas and used as single client radio adaptors for AVGs running around a plant floor
- used in MESH mode to connect smaller network islands of automation
- standard point to point links
- stand-alone access points for specific cabinets
You get the idea; flexibility is these radios middle name.
The throughput speeds that these radios maintain, while certainly not gigabit, are more than enough for most industrial applications with plenty of room to spare. However, if you are looking to link up with multiple HD wireless cameras transmitting at full 4K video resolution, then the 2102/2011 series may not be for you.
The nice thing is that these are not super expensive. A quick internet search (practicing my Google-Fu) shows that the average retail price for a single unit is approximately $700 (this was for base cost of the radio, not including any additional support or accessories). Most sites give discounts for multiple unit purchases too. Conceivably, if you are looking a multi-radio MESH deployment, you could really keep your hardware costs down.
Overall, I think these are great APs at a reasonable price point and can support numerous roles on the factory floor.
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