correct, There are quite a few brands using either 24v or 48v, designed to run off POE (its a pain there are two standards)
:-(
CCTV, workshop security
- Thread starter Housey210
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:-(
Mine are Unifi (using 2 LR routers- still to be installed)
The 'flying saucer' lol
I have one up 5m in the air already, that one is going at the gate, once I buy the metal pole and do all the installing required (its right at its limit, I tested it holding it up in the air at the gate on a broom handle lol- it links, but the throughput at that distance is well down from its rated ghz range- but I don't need that kind of speed for a single camera (ok maybe two), and the intercom and gate remote...
The ones using 24v tend not to be compliant with 802.3at as they use proprietary connections even though it is down standard CAT cable. The issue there is you can’t use other devices or standard PoE routers - they usually use PoE “Injectors” which are used as pairs to apply/extract the voltage on the spare cable pairs and the wiring then is up to the vendors. I’ve seen injectors using both spare pairs as +/- and it creates noise on the Tx/Rx pairs. For installations that don’t need to be highly secure then IP cameras on PoE are probably the quickest and easiest route.
How about cutting excess cable and use Wago connectors?
802.3at PoE is 48v, 802.3af PoE is 24v... (usually)
Then there are the 'propriety' ones that use whatever they want- a pain when you are mixing and matching...
The difference in at and af is the power not the voltage - af is the PoE standard at 15.3W max, at increased this under PoE+ to 30W and bt is now available to take to PoE++ in carrier class units which is between 60-100W per channel.
Useful link here on what can be powered by each type
https://community.fs.com/blog/understanding-poe-standards-and-poe-wattage.html
Like phones and their 'fast chargers' the POE injectors have increased the power, but as the cables are the same, you can have the same amperage (limited by the cable size). but increased wattage by upping the voltage...
(W=VxA for those who aren't into the electrickery stuff on the side)
(you want more watts, you need to make the volts bigger, or the amps... The amps is limited by the cable size- to increase them, you need thicker cables- or you raise the volts instead... Raising the voltage has the added advantage of making the voltage drop caused by the cable resistance to become less of a % of the supply voltage- A 5% drop caused by the resistance of the cable at a specific voltage and wattage is smaller in voltage terms the higher the voltage is...)
Thats why say cross country powerlines are hundreds of thousands of volts, rather than 240v... if they were at240v, those cables would be the size of a bus!!!!
(none of this is aimed at you btw PDW125, just for those who might not be versed in the magic electrickery stuff lol and why any of this matters)
(W=VxA for those who aren't into the electrickery stuff on the side)
(you want more watts, you need to make the volts bigger, or the amps... The amps is limited by the cable size- to increase them, you need thicker cables- or you raise the volts instead... Raising the voltage has the added advantage of making the voltage drop caused by the cable resistance to become less of a % of the supply voltage- A 5% drop caused by the resistance of the cable at a specific voltage and wattage is smaller in voltage terms the higher the voltage is...)
Thats why say cross country powerlines are hundreds of thousands of volts, rather than 240v... if they were at240v, those cables would be the size of a bus!!!!
(none of this is aimed at you btw PDW125, just for those who might not be versed in the magic electrickery stuff lol and why any of this matters)
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One of the funniest things I saw just before I retired was a remote POE camera modification at one of the units I supported. The technician was tasked to install a camera in a remote area, which was well beyond the range of the copper cable. Instead of asking for help, he decided it can't be that difficult and spent about two weeks trying to troubleshoot his project until his Commander called for help. The technician added a media converter to the POE injector output, ran several hundred meters of OC3 fiber to the camera location, and then put another media converter at the camera end. He was clueless why it didn't work until I explained the problem to him. We approached the problem with a different solution to meet the Commander's intent.
Had a look at the site, some really good stuff on there. and good prices considering the technology. Are you able to get connection with these units, or do you need a high gain antennas? What speed did you get with your broom test? Did you have to get above the tree line?
Well the
The LR has its own internal antenna, indeed it has no provision for an external one...
I was well below the treeline (I was standing on the tailgate of the ute, holding that exact LR electrical tapped to a broom handle- it wasn't that high... and the trees are much higher than I'd plan on putting it (I need a way to lift anything higher than a 5m pole up into the air- they aren't light...)
The one already in the air is on a TV antenna J pole at the peak of the shed roof- making the LT about 7 to 8m above ground level...
The other one was tested where the gate now is (where the mail lockbox is a bit down the driveway) it was maybe 3.5 to 4m up in total, the final one up the metal pole will be 5m up- that gate is exactly 500m away from the shed...
Getting above those trees would be 'problematic', many are 10 to 12m tall, some higher...
The camera could hit its full speed (I didn't have any way if actually doing a speed test, as I wasn't going to drag the laptop and the inverter down to the gate lol (its internal battery died years ago- its well over decade old!!!)
The LR has its own internal antenna, indeed it has no provision for an external one...
I was well below the treeline (I was standing on the tailgate of the ute, holding that exact LR electrical tapped to a broom handle- it wasn't that high... and the trees are much higher than I'd plan on putting it (I need a way to lift anything higher than a 5m pole up into the air- they aren't light...)
The one already in the air is on a TV antenna J pole at the peak of the shed roof- making the LT about 7 to 8m above ground level...
Getting above those trees would be 'problematic', many are 10 to 12m tall, some higher...
thanks for that. My son in law's place has a band of oak trees about 5 trees deep and this time of year, they are in full foliage. it sounds like it might still get usable bandwidth. Once you do get it all set up if you ever do a speed test it would be interesting to see the results.
Update
Voltage readings at camera. 18mtr factory terminated lead - daytime reading 11.68v. Night time reading with leds on 10.49v- 1amp.
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Your daytime reading looks OK, but I feel that the night time value is a little low. The ultimate solution is to do what others have suggested and fit a 12V regulator at the camera end of the long cable, with a higher voltage supply feeding it at the other end. A heavier gauge cable is also an option, but perhaps more tricky to install. Or you could do as I've done and use one of those variable output supply things which can be found on Ebay - I started it off at 13V and bit by bit increased that until the dropouts stopped. I have no idea what the voltage is at the camera end, but it is still working fine after a year or so.
G.
G.
Awaiting delivery of a dedicated psu, fan cooled with variable 2v voltage increase, so I just hope that solves the issue. If not, then the 12v regulator may be the solution. thanks to all
