I hoped to run an R200P powering an ePMP 5 GHz SM and an ePMP Hotspot (on the auxiliary port) as follows:
12V Supply --> R200P --> ePMP SM --> ePMP Hotspot
It seems 2 radios are too much of a draw on the R200P. The primary radio reboots every time the secondary radio tries to start.
I had not noticed a POE power rating, but I assumed with a provided 12 Volt, 3 Amp (36 Watt) power supply, it could handle at least 2 radios. Is there something I'm missing? Configuration change on the R200P? Can it simply not handle this output? With the R200P powering one ePMP, the total power draw I'm measuring is only 4.6 Watts.
We only intended one SM, PMP or ePMP, to be powered at a time from the PoE port, so the port is designed to power and communicate with only one. You may be drawing more power than the port can handle or you may be seeing a limitation we didn't find because we did not test with two radios connected. We will change our documentation to make it more clear what is officially supported.
Your answer also makes me curious about the power draw. We see much higher power draws than 4.6 Watts for two radios. Was the R200P or ePMP SM sending data over their RF link?
Your answer also makes me curious about the power draw. We see much higher power draws than 4.6 Watts for two radios. Was the R200P or ePMP SM sending data over their RF link?
The 4.6 W measurement was with only the R200P and ePMP SM. Neither were actively sending data. When I have all three connected separately, I was measuring 7.9 W (also not sending data). This makes me wonder where the power output cutoff is (If it cannot handle the radios at idle, what about a radio transferring data on a long cable run?). Perhaps I'll spend some time checking power consumption under various conditions another time.
Thank you for clarifying. I think it would be nice for the R200P / R201P PoE output to at least match that of the included ePMP power adapter. Further, a maximum current specification in the data sheet would help.
I want to say I remember hearing that the 200P WAN PoE is designed for a 10 or 12 watt max load (350 or 400mA, basically the same as a standard Canopy/ePMP PoE brick), which would pretty much be the upper limit for something like a 450SM on a 120-150 foot cable run.
If we daisy-chain a Canopy or ePMP to the aux port of an ePMP SM, we use only the Laird POE-24-iR since it's rated 800mA at 24VDC.
We did design the 200P and 201P models to deliver 12W max load to a PMP or ePMP SM at 100M of ethernet cable, which would be the highest power consumption use case in a normal configuration. Chris may have run into a problem unrelated to power with the three radios all connected at once that we did not test. Both the ePMP and Hotspot consume much more power when transmitting anything, so if they both tried to transmit at the same time, I could easily see them combine for more than the 12W max load.
We are updating the cnPilot Home User Guide to make it clear only one SM is supported. The user case of powering a SM and a Hotspot or other accessory probably isn't common enough to justify redesigning the cnPilot PoE.
There are use cases for some I'm sure, but probably not us.
For example, we have installed 450 SMs on a customer's barn or other out building to get LOS and used integrated ePMP radios to power the 450s and also to shoot to an ePMP integrated SM at the customer's house. In that example, we wouldn't need the 200/201P in the garage/barn, just a Laird POE.
The only possible case I can think of is a neighbor has LOS, but a potential customer doesn't want 900MHz service, so simply adding an integrated ePMP to the existing customer (on the existing line and not needing to add a second cat5 cable) would be useful. But again, we can just swap them to a Laird POE.
I would agree with the assessment that changing the WAN POE to provide more current is probably not worth the effort.
We did design the 200P and 201P models to deliver 12W max load to a PMP or ePMP SM at 100M of ethernet cable, which would be the highest power consumption use case in a normal configuration.
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We are updating the cnPilot Home User Guide to make it clear only one SM is supported. The user case of powering a SM and a Hotspot or other accessory probably isn't common enough to justify redesigning the cnPilot PoE.
I'm not specifically concerned about how many SMs are supported, I'd rather just know the power output and work out the details from there (12W, as you stated). I was just surprised that the output could not handle two ePMP radios.
I've been told the R200P will run a PMP450 radio. Working backward, the PMP450 SM spec sheet states the maximum power consumption as "12 W (5 GHz AND 2.4 GHz), 15 W (3 GHz)". With the assumption that the R200P would be designed to handle the maximum power of a PMP450 (15W) and some reasonable length of Cat5e, I figured it could handle 2x ePMP radios that are specified at a 7 W maximum each (total 14W), especially if I was running a very short cable length.
I realize the reasons for running dual radios on an R200P are minimal, and I would certainly not request a "redesign" just for my handful of examples. I do think it should function as intended, though. My [perhaps rusty] math suggests a 12W max PMP450 5GHz radio on 100m of 0.15 ohm/m Cat5e will have a power loss around 4.5W. This would suggest the PoE output should handle 16.5W or more, plus some margin (and higher for 3 GHz radios).