Wiring 4 PTZ done cameras

[_Spud_]

Hello all, this is my first post so a big hello to you all.

I am looking at wiring 4 PTZ dome cameras running on the Pelco D protocol to a small controller board, I need to know how I would wire this unit.

I know I need 2 cables RS485 + & - so I was planning on using Cat 5 cable (2 pairs of cable) my question is, do I run one CAT5 cable to each PTZ camera and then back to where the PTZ board is and put them all into a multi block and then into the CCTV system, or do I have to run one cable from camera 1 to 2, from to 3, from 3 to 4 then 4 back to the controller board.

I hope this makes sense; I have never wired a PTZ camera before.

Thanks

[Rich]

As long as the domes are addressed correctly it shouldn't matter which way you do it, Are you not using coaxitron convertors over coax to each camera?

What cables are you intending to run to each camera?

[_Spud_]

As long as the domes are addressed correctly it shouldn't matter which way you do it,  Are you not using coaxitron convertors over coax to each camera?

What cables are you intending to run to each camera?

31548[/snapback]

hi, i was going to run RG59 to each cam, as well as Cat5 for the PTZ system.

[Rich]

If the cameras are close to each other then run the control from one to another, if the cameras go off at very different directions and connecting one to another would be alot of work then use a star network from the main controller like you say, maybe it would be worth looking into coaxitron control from the controller so you only need to run the coax.

What is the controller board you are refering to and what unit are you using to control the domes (model)

[_Spud_]

If the cameras are close to each other then run the control from one to another, if the cameras go off at very different directions and connecting one to another would be alot of work then use a star network from the main controller like you say, maybe it would be worth looking into coaxitron control from the controller so you only need to run the coax.

What is the controller board you are refering to and what unit are you using to control the domes (model)

31550[/snapback]

Thanks

If I setup a star network, would i need to do anything else, i.e buy any other hardware?

The cameras are about 150 meters apart; I would prefer to put a star network in as it would be much easier for wiring.

I am unsure what cameras/domes are going to be used, all I know is that they are standard RS485 running on Pelco D protocol.

I know the unit that they are going into is a remote access Linux based DVR unit, the unit has a connector on the back setup for RS485 connections, well I believe it goes threw a comport into a small RS232 converter to RS485

Where do I get a

[Rich]

Ive sent you my msn on condition that once you have got it all worked out and everything is fine that you come back to this post and make it clear what you had to do so everyone can benefit from it.

[ian.cant]

Im not a pelco boffin but i would suggest belden would be better for telemetry(shielded twisted pair).

[CompostCORNER]

Im not a pelco boffin but i would suggest belden would be better for telemetry(shielded twisted pair).

31799[/snapback]

I remember ringing VCL a few months ago after a fellow engineer had ran 8 core alarm cable some 250 meters strictly for twisted pair telemetry. What the chap from VCL said, didn't half surprise me.

He said that you could actually run two lengths of wet string through each dome making sure it's all in series and ID'd correctly and the system should work. He said that the signals down this string would only deteriorate if the string was installed where it could pick up electronic interference.

I still told my fellow engineer to run Beldon anyways otherwise I'm sure we'd now be installing string as company policy.

[Brian c]

signals down this string would only deteriorate if the string was installed where it could pick up electronic interference.

32733[/snapback]

Hence Ian's recommendation of Belden (Shielded) twisted Pair!

[Guest cctvman]

As the other post's say belden

The longer the run the worse the signal gets

Key Points :!:

Make sure that you earth your screen cable to a nice clean earth, dirty earth will produce noise when can affect transmission & give false signals (roaming dome)

Calculate what the total run will be if it's a long run use a scope to see voltage drop & any bad data or pick up

Remember you wiil probley have your power running in the same duct which does give off rf so use decent cable

If its a screened cable to the dome head make sure you follow the earth loop

Daisy chain is better but not always poss, use a stardiver @ the control end & most will boost the launch signal to each camera

Poor signal fit an amp half way down the line & that goes for the video signal too

Spare cores ? if your data cable has spare core use them it will increase signal

Phew !

Last & not least you may instal a system that works fine for a year or two but problems will appear if it not done right spent a year working on & off a system that was in for 3 years most service tech just changed the domesbut the problem would move from dome to dome, poorly installed & to think what the company i worked for lost in profit with my time on site @ no charge to the customer

On the spectras great domes although a bit of a nightmare setting up in low light with the digital zoom/focus but other than that thumbs up 9/10

Regards

Cctvman