Looking for combined / hybrid cable

[Stuart91]

I've got a little project on the boil, trying to get some PTZ CCTV cameras working in an elegant and easily-deployable fashion. Partly for a demo rig but also on-stage use when things start back up again.

 

Ideally I'd send a 12v supply along with two twisted pairs: one to carry the video signal and the other for the RS485 that's used for PTZ control. The power required means that at 12v the current required is going to be too much for the standard twisted pairs, so I'm looking for an option that's got separate cores for power, ideally 1 mm2 cross-section but I could scrape by on less if I keep the lengths under control.

 

It's a bit of a challenge finding a suitable cable. I can turn some options up online, but like this they're aimed at wholesalers. I'm only needing a couple of hundred metres, not 200 boxes.

 

Struggling to turn up anything via Google, probably because any search terms are turning up irrelevant results about PoE or various baluns etc.

 

Has anyone come across a potential (UK based) supplier?

Edited August 14, 2020 by Stuart91

[Dave m]

Would a rugged cat 6 do?

https://www.amazon.co.uk/MutecPower-Outdoor-waterproof-Ethernet-Network/dp/B00EOTHDWQ/ref=asc_df_B00EOTHDWQ/?tag=googshopuk-21&linkCode=df0&hvadid=309903005216&hvpos=&hvnetw=g&hvrand=4781234355672329188&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9050362&hvtargid=pla-565476416398&psc=1

[Stuart91]

Thanks, Dave. I might be missing something but it looks like the cable you've linked only has the standard four twisted pairs. More than ample for the signal transmission I need, but probably not enough cross-section for the 12v supply.

 

I've edited my original post since I suspect I wasn't clear enough.

[Glyn Edwards]

Syntax Cables produce a combined 2 x Cat5 & 1.5 sq mm mains cable. Probably overkill for your purposes but...

 

Sommer Cables may produce something useful...

 

Or this one?

Edited August 14, 2020 by Glyn Edwards

[Stuart91]

Probably overkill for your purposes

 

Correct, but it's an attractive option for getting out to a FOH desk - will keep it in mind for that.

[Dave m]

Would something from a cctv system be possible? Pretty use all our work cctv is mains powered before being sent back to monitoring but something between domestic and massive?

[Stuart91]

It is essentially CCTV cameras that I'm trying to run with this, so I've tried various suppliers and not found anything suitable. There's plenty of the traditional "shotgun" style cable around that has two-core power and an RG59 coax side by side. I'd take something like that if it had a CAT5/6 there instead of the coax.(There are versions that have CAT6 + coax with no power, but I can't see anything that's CAT5/6 + power)

 

Most IP cameras seem to be either mains powered or PoE - it seems like I'm sitting in a slightly awkward halfway house.

[Yorkie]

Can't work out whether the camera you're referring to uses one twisted pair or one cable of several twisted pairs for the video signal. Assuming it's one pair I found the following with some extended googling

 

Twin DMX plus 2x1mm power: (Light grey, 200m drum ~€400) https://gothamcable.com/en/gothamcables/dmxled110ohm/10682frnc2dmx230vacfrncled

Sommer Monolith 2: Twin DMX plus 3x1.5mm power https://shop.sommercable.com/en/Cable/Bulk-Cable-Audio/DMX-Power-SC-Monolith-2-500-0051-2.html

Cordial CDP 2-25:: Twin DMX plus 3x2.5mm power https://www.cordial-cables.com/en/products/cdp-2-25

Syntax 7XD2F315SX: Twin DMX plus 3x1.5mm power http://syntaxcables.valentiniinternational.it/sito/schedaprodotto.php?id=13

Cat 6a plus 3x2.5mm power: https://kelseyacoustics.co.uk/product/kelsey-combi-2/

Twin DMX plus 3x1.5mm power: (seller in China) http://propaudio.com/product/hc02p15-composite-cable-power-3g1-5-2x-DMX-cable/

Cat 6 plus 2x LV power https://tmb.com/proplex-powerdata-lv/

[musht]

What's wrong with PoE, got a IP PTZ camera at about 160ft on Cat5, uses PoE+, 60W delivered at lot less cost than the 100/72W delivered PoE stuff.

[timsabre]

Low tech suggestion but if it's only a couple of hundred metres, couldn't you DIY by taping 2 cables together? I've seen and used plenty of taped FOH multis.

[david.elsbury]

If it’s RS485 you want; remember that DMX is pretty much RS485....

sounds like a perfect job for scroller cable. Anyone remember scrollers? Ah, fond memories ;)

[gyro_gearloose]

I’m assuming your cameras are IP cameras, since you mention using twisted pair for video transmission. What’s the maximum voltage you can send down Cat5/6? Since your problem seems to be that you need 12VDC at a reasonable current, can’t you bump up the voltage that you send over the Cat5 and then step it down again at the camera? Voltage goes up, amps go down.

[musht]

Guessing it's not IP, on stage use , lag may be an issue.

 

802.3BT is '100W' PoE, actually 72W delivered, at up to 56V.Switches are expensive.

 

PoE + delivers 60W at lower cost.

 

Mebbe use midspan injection and splitter to carry power and SD video.

Edited August 15, 2020 by musht

[Tom Baldwin]

TMB sell "shotgun" style dual Cat5e cable: here - you could use two of the pairs for video & RS-485, and the rest for power. By my reckoning, you have 12x 0.22mm2 conductors available for power.

In a similar spirit of combining lots of conductors, there's Canford 8-pair FSM which is a single 11mm diameter cable

 

I had wondered about running a higher voltage down the cable and then dropping it at the camera, but introduces more active devices in the system which could fail, cf. the passive approach of the "right" cable.

[Stuart91]

Hi folks,

Thanks for all the contributions.

 

The camera's aren't IP, they are using TVI, which can run down bog standard RG59 coax but can also be adapted to come down one pair of a CAT5 or 6 cable. The control for the PTZ is RS485.

 

I'm keen to avoid a taped loom, partly for neatness but also for ease of deployment, I'm thinking I might be able to use a single connector (with a breakout box at the camera) if I can find a cable with a small enough outer jacket.

 

I'd originally hoped to be able to use a single CAT5/6 cable, using two pairs for the signal + control, and ganging the other two pairs together for power. But according to the manual the cameras will draw 1.7amps @ 12v. Plus I'm not sure how tight the voltage requirement is, I wouldn't want them flaking out if the delivered voltage drops over a longer run.

 

One suggestion I've had was to use 48v for the run, and step down at the camera. That would probably run happily down two pairs, maximum run is going to be 50m tops. But as Tom suggests it adds complexity, and I think I'd be happier getting the right cable, even if it means a bit of compromise on the form factor.