Communications between two SLC 5/03's and a PV 550

[demmons]

I currently have a SLC 5/03 1747-L532 communicating to a DTAM via DH485. I would like to add another SLC 5/03 and replace the DTAM with a PV550 that will communicate with both SLC's.

I know I can set up the DH485 network using 1747-AIC modules, but as speed is not an issue, and cost is...

Is there a way to have the PV communicate with both SLC's without using the AIC modules?

Thanks

 

[Eddie Willers]

Isolator modules are not that expensive, compared to the toasted machines they prevent.

The smallest network I could envision for this would use a single 1761-NET-AIC module, which has two RS-232 ports and one DH485 trunk connection. You can connect each SLC-5/03 controller via the serial port to the two RS-232 ports, and connect the DH485-equipped PanelView 550 to the trunk port with a 1761-CBL-AS03 or -AS09 cable.

There are quite a few permutations because the SLC-5/03 can run DH485 on its network port or on its serial port, and PanelView 550 terminals can be obtained with DH485 protocol on either a DH485 network port or on an RS-232 port.

If you already have the PV550, or if you need to keep the SLC-5/03 Channel 0 serial ports available for online programming, the "lowest cost" answer will change. It will also change if the second controller is more than about 30 feet from the first controller.

Unless you are building an OEM product, I strongly recommend that you connect these controllers using the proper isolator modules. The couple of hundred bucks you spend today will be forgotten, but if you cripple your maintenance access or the network is unstable, your network decision will be remembered.

 

[demmons]

Thanks Eddie,

I also brought up another option to the boss, use two C600 panel views (one for each SLC), communicating via serial cable instead of a single PV550.

The price for this option is actually a little bit less than the price for the PV550 alone, and a lot less complicated.

Thanks again for the input.