Connecting A Rs485 Dome To 2 Controlers, Is This Possible?

[Alexg]

Guys,

At the moment we have a Ultrak KD6 dome connected to a Ultrak Diamond series controller via 1 twisted pair.

I have now added a new videoswitch VI400 DVR which has the capability to connect a dome to it.

I would like to do this so I can controll the dome off site, via the DVR.

Can I just connect the 2 in parallel so either of them will controll the dome, is this possible?

Thanks.

[jelly belly]

I'm not sure about Ultrak but normally you can't have two control sources like you have if either controller polls the Dome. This will cause a conflict. Sennetech make a Code merger that gets around this problem. http://www.sennetech.net

Jelly Belly

http://www.software4cctv.co.uk

[C.S TEK.]

You can fit a relay that trips when you dial up and switches over the data. A bit like when you set some system up on Adpro and monitoring take over.

Chris

[Alexg]

ISC,

Can I use a standard relay on the RS485? or will this mess up the data transmission, I can trigger a relay in the DVR remotely...

[Matt the Teckie]

ISC,

Can I use a standard relay on the RS485? or will this mess up the data transmission, I can trigger a relay in the DVR remotely...

The problem you have with using a relay is that when the switch closes, it can bounce very slightly. This action can generate a signal that other systems can perceive as an instruction. Depending on the resiliance and error checking capabilities of the RS485 drivers, this can cause lock up problems and spurious dome movements. You're always better off using a proper data switch, it might cost a few more quid but at least you know it'll work.

Just as a side point, sites that have an Adpro system on site in addition to a matrix switch often use this kind of system to switch between on site and off site control. Do the Videoswitch product and the Ultrak controller share a common data protocol? If so, why use the Ultrak controller at all?

[Alexg]

Yes they do share a comon protocol, is the box that Jelly Baby posted about a data switch? I couldn't actually work out what it does.

Yes I could technically control the domes solely from the DVR, I'd need to get a joystick controller for it though, might be the better soloution I guess.

Thanks for your help