power over long distances

[gavin.sibley]

Hello all,

Been asked to look at a project involving running power to CCTV cameras but over stupidly long distances, just wondering whether anyone on here had any experience with such things that could maybe help me out. And by long distances I mean up too 1 mile!!

Cheers,
Gavin

 

[telectrix]

well, 2.5 would have a R1+Rn of around 1K, so sereios VD issues. would not even attemmpt it.and that's without considering the signal transmission.

 

[gavin.sibley]

Signal transmission isn't an issue I've covered that hurdle, what I need to do now is send either 12/230v out to 16 cameras along a one mile run, each camera position will need approx 1.5 amps of power (230v) all will be in ducting underground

 

[shanky887614]

Signal transmission isn't an issue I've covered that hurdle, what I need to do now is send either 12/230v out to 16 cameras along a one mile run, each camera position will need approx 1.5 amps of power (230v) all will be in ducting underground

Can't you run a submain closer?

Would need a stupid size id guess at least 6/10mm

I could be completely wrong mind because I havent bothered to calc it

 

[telectrix]

thinking outside the box.... 17AH battery ( 12V ) with solar/wind charger?

 

[jeremy]

You don't say where these are but for really remote situations we manufacture a power cabinet that has about a square metre of PV and a hydrogen fuel cell. These are totally self sufficient for a year. Laser cutting, waterjet cutting and engineering fabrication from ICEE - Remote Power Enclosure Hydrogen and PV Solutions | Laser cutting, waterjet cutting and engineering fabrication from ICEE

 

[Davey1988]

Jeremy if you dont mind me asking what happens after a year? New hydrogen fuel cel required? Is the output 240v and do they last all day how much supply could you get out of a full charge etc

 

[Deleted member 9648]

Assuming a 1 mile length @1.5a a 10mm SWA would give a volt drop of around 11v.....so the furthest camera would need at least that.You would need to work out loadings and distances to each camera back from that to establish cable sizes for each section. Not very practical is it?.....As above....some sort of solar battery system has to be favourite.

 

[telectrix]

and the 1st @ 48A VD would be about 80V on 10mm. need some serious amount of copper for the first 8.

 

[D Skelton]

Are you sure their operating current is 1.5A? I would have thought it'd be more like 0.15A. Most mains cameras have an input voltage of between 100-250V, therefore you wouldn't need to worry about dropping shed loads. 2.5mm over a mile drawing a total current of 2.4A (16 x 0.15A) would drop 70V at the furthest end. This is only a quick calculation though and doesn't take into account the loss of 0.15A current draw every 100m so in reality your actual voltage drop is likely to be closer to 60V at the far end.

If your supply is 230V and you're only dropping 60V making 170V, then it doesn't matter one bit if your cameras will operate with a 100V input. You'd probably even get away with supplying them with 1.5mm!

 

[telectrix]

even the small dome cameras for internal use take more than that, D. i've had to fit 5A PSUs to feed 4 casmeras several times. where the original installer had used 1A PSUs. the infra red illumination takes a fair bit of juice.

 

[D Skelton]

even the small dome cameras for internal use take more than that, D. i've had to fit 5A PSUs to feed 4 casmeras several times. where the original installer had used 1A PSUs. the infra red illumination takes a fair bit of juice.

We are talking amps at 12V, milliamps at 230V Tel

 

[telectrix]

DOH. brain fart.

 

[telectrix]

yep, makes sense. 1.5A @ 12V is probably what OP meant. a lot of external camera housings have heaters, though, to stop misting.

 

[gavin.sibley]

sorry all for the slowness of response, just doing some planning and researching as i go along on this project. The cameras in question are something like these:-

Samsung SCP-2370TH 37x Zoom Auto Tracking External PTZ Domes Camera

these are showing a spec of 60w (max) at 24v - giving infact a total power consumption of 2.5A per camera, we will also be running some other equiptment on the bottom of each mast point but this comes to no more than 0.5A at most.

I like the idea of solar/wind, but how reliable could that be in terms of never loosing power to the units? bearing in mind i have to pull in a mile of signal cable anyway so putting in a power at the same time shouldnt be too bad!

thanks for the help so far,
gav