Created Date: May 24,2012

Created by: bcarlton

In the 'Address Picker ' be sure to enable the 'display MODBUS Addresses ' in the lower right. This will give you Modbus addresses of the Slave unit. You will place all communication instructions in the Master. From the Master send 'X ' input states to Slave 'C ' bit states. Similarly read Slave 'X ' input states into local 'C ' bit states.

For communications check establish a self-resetting timer in each unit using a 1 second time base and timing for a minute (value not really critical). Each cycle send the accumulated value of the local timer to a Slave number location. Also read the slave's accumulated time into a local numeric variable. Code in each unit should be checking for the other's timer value changing. If it stops, then assume communication is down and take appropriate action.

Created Date: May 31,2012

Created by: speakerman

Hey shawn8791;

In the D2-260 I send SP4 as a heartbeat toggle, with a POSCON and NEGCON resetting a TMRAF set to one second as the confirmation watchdog. This gives me a half-second refresh resolution, which is okay for non-critical applications and 1/2 sec is much slower than any comm should be. If you need faster response for safety and the comm rate is fast enough you can use SP5, for 50ms on/off, and a lower setting for the TMRAF. Depends on the speed of the comm versus safety of the system - how long is it safe for the outputs to persist when comm is lost, versus nuisance trips for tiny comm interruptions.

Do they have the SP4 and SP5 bits in the click? Haven't used that processor yet.

Speakerman.

Created Date: May 24,2012

Created by: shawn8791

Does anyone have a program example that I could look at for an example of how this works or some explanations? I have read the manual and can get the communication to work but am a little unfamiliar to the addressing of the communication values. I am basically needing to put one PLC on each end of an energy chain to eliminate most of the wires thus using a communication cable instead of many different I/O wires. I will just need to get an input to one PLC and make it an output on the other. This will go both ways as there will be both discrete and analog signals that will need to go to and from both PLCs.

I am using an analog Click PLC C0-02DR-D and using the RS-485 port3 with Modbus protocol.

Any help would be appreciated.

Thanks