Wireless SLC network

[tjmurf]

Does anyone have much experiance with wireless networking using SLC's As usual, the AB solution is very expensive. I like the ethernet speed but don't the $2000.00+ price tag for each 505. I am going to settle with 503's

What advantages are there using a DF1 to ethernet converter, 1761-NET-ENI.

Will I need to reprogram any existing message instructions that exist on the DH-485 network?

Any third party 2.4gig radio modems that are less than $800.00 ea

I'll have 6 slc's with 2 workstations. 3 to 4 will be wireless. All less than 1000'

 

[youcantbeserious]

I have completed a number of projects using SLC5/03 with various radio telemetry types. Most recent comprised 3 SLC5/03 Outstations communicating with a Master SLC5/03 via DF1 protocol at 9600bps using radio modems. Data was volumetric flow, totalised flow and discrete digital signals.
The radio acts as a serial link simply passing data - it is transparent to the PLC. It is a short range device operating at a frequency of 458.825MHz (unlicensed in UK)
Each PLC has to be configured to be slave or master and data is best located in contiguous blocks.
A MSG instruction in the Master reads specified data addresses from each specified Node. Thats it.
If you require further detail - just ask.

 

[tjmurf]

Have you ever used Ethernet/IP?

Any problems with using the 458.825MHz band?, and how far apart are your radios?

 

[youcantbeserious]

Hi,
1. Not used Ethernet/IP myself.
2. No problems experienced with radio band - supplier carried out a frequency scan to determine how busy. Installation is on a large Chemical site with lots of large structures and other radio systems.
3. Largest distance is 1320 metres.
4. I have copied the Slave PLC seconds register to the Master PLC as a 'heartbeat' check. This produces an alarm on the associated Wonderware InTouch Scada on loss of heartbeat.
5. Each PLC has a DH485 Panelview connected to Channel 1 and the Wonderware is connected via a Link Coupler over DH485 and a 1770-KF3 converter.

This was an overall satisfactory solution, cheaper than the original proposed Modbus SLC.