Ubiquiti NanoStation loco M2 question

[Maverick52]

So I want to use a pair of these nanostations to setup a remote camera and view the camera's feed with an android device. The basic idea of this is I want...
[wireless IP camera] <-> [loco M2] <-----------> [loco M2] <-> [Android device]
If I need more hardware than this please let me know, I haven't messed with these yet so I'm in unknown territory.

Because this is a remote setup I will not have access to power, I need to run everything off battery, but I only need to run it for a few hours. I think I can accomplish this by using a 20,000 mah phone/tablet charger style battery pack. I know I can get a camera that will run off the 5v from the battery pack, however the nanostations are using a 110vac to 24vdc, 0.5a PoE injector for power.

Since I have no access to 110vac I want to supply the nanostation using a dc to dc booster converter to take the 5v, 2.4a from the USB plug on the battery pack and convert it to the 24v, 0.5a. I was thinking this should be as simple as taking a USB cable, splicing it to the input side of the booster and then taking the cat cable and splicing it to the output side of the booster. However, I am unfamiliar with PoE devices and I'm not sure if by excluding a "off the shelf" PoE injector am I getting rid of any functionality that I will need? I've also looked but cannot seem to find a PoE injector that is setup to work in those 2 voltages except the Ubiquiti AIRGATEWAY PRO INSTALLER but this PoE injector seems to be quite a bit more expensive than needed if I can simply use the dc to dc converter.

 

[bill001g]

It would be nice if they did not call multiple things PoE. The standard is called 802.3at and uses 48volts. It is a active protocol so no power is provided unless the device requests it. This can not be replaced by a simple voltage converter. There are also passive PoE devices. These provide the power all the time and you could just wire up the voltage to the proper pins...normally 7&8. Most these systems run less than 48 volts.

Ubiquiti sells both types unfortunately so you will have to read there documentation to see which. Some of their models they sell both kinds with a slightly different part number. I don't remember what the loco ones can do.

If it is a passive system you might get it to work. It might be simpler to use a couple small 12 volt batteries used for UPS that to mess with voltage converters.

Although most ubiquiti stuff runs the same software and it can run as a wireless repeater I am not sure it will work with directional bridges. The antenna are pointed the wrong way to let your wireless camera and android get a signal. They are designed to point to point use. Normally you plug things in via ethernet. You would need a small AP connected on both ends to provide the wifi if I were doing it.

I have used ubiquiti devices many times at point to point bridge. I have even played around with the router function but I never tried the repeater part. That is more used by their devices that have a second antenna or on their non directional equipment.

 

[Maverick52]

It would be nice if they did not call multiple things PoE. The standard is called 802.3at and uses 48volts. It is a active protocol so no power is provided unless the device requests it. This can not be replaced by a simple voltage converter. There are also passive PoE devices. These provide the power all the time and you could just wire up the voltage to the proper pins...normally 7&8. Most these systems run less than 48 volts.

Ubiquiti sells both types unfortunately so you will have to read there documentation to see which. Some of their models they sell both kinds with a slightly different part number. I don't remember what the loco ones can do.

If it is a passive system you might get it to work. It might be simpler to use a couple small 12 volt batteries used for UPS that to mess with voltage converters.

Although most ubiquiti stuff runs the same software and it can run as a wireless repeater I am not sure it will work with directional bridges. The antenna are pointed the wrong way to let your wireless camera and android get a signal. They are designed to point to point use. Normally you plug things in via ethernet. You would need a small AP connected on both ends to provide the wifi if I were doing it.

I have used ubiquiti devices many times at point to point bridge. I have even played around with the router function but I never tried the repeater part. That is more used by their devices that have a second antenna or on their non directional equipment.

If I've read the documentation for the M2 correctly it runs on 24v, 0.5a from the provided poe injector that comes with it. This is why I thought using a voltage converter to go from a USB 5v, 2.4a would work as the math lines up perfectly.

Could you explain why providing the 24v from the converter wouldn't be the same as providing the power from a passive poe device? To me it seems the same, so maybe if I understand the difference then I can get on track and figure out what I need to do.

I'm hoping the M2 wont need additional ap's at each end but if so I can take care of that pretty easily. Once I figure out how I'm going to power them then I can at least set it up and play with it to see what/how it works.

 

[bill001g]

A voltage converter will work in theory but they are not 100% efficient so you actually need more power going in than comes out. Then again most equipment does not actually use the full amount of power the included power supply provides.

You will have to build a special "cable" to connect inject the power. You need to see if ubuiquiti documents which pins are used for what. With passive power there is no standard so vendors can be different. Testing with a voltage meter would work. Most passive systems do not pass data over the same wires as the power which limits them to 100mbps.

 

[Maverick52]

You're right, there will be some loss. I would think the M2 would probably run fine though since it's spec is 24v, 0.5a and that is the max, it likely draws less amperage under normal conditions. If the loss was a problem I might be able to use a battery pack with multiple ports and wire 2 of them to the boost converter with the single output.

My plan was to basically make my own "cable" with the USB on one end, RJ45 on the other, and the boost converter in the middle. I planned to check the provided PoE adapter with a DMM to verify polarity & on what pins. Same with the USB.