teamfrisbee
Member
Hi,
I am working on a project in which I kind of have to "use the resources at my disposal as best and cheaply as possible." I need some help troubleshooting the system.
The situation is as follows... I have a master site, repeater, and remote site. The master and remotes both have S7 315-2 DP (315-2AF03-0AB0 / V1.2) PLCs, as well as MDS 9710A Licensed Radios. The repeater is an MDS of some sort (I have yet to see it).
What I would like to do is be able to poll the PLC at the remote site using the built-in Profibus ports on the PLCs. There is no additional Profibus hardware at my disposal. Speed is not really an issue here, 9600 baud is acceptable.
If these PLCs were next to each other (but same concept applied), it seems like the method would be to use I_PUT and I_GET instructions. At least this is what I have gathered from Hans Bergers' books and the use of intelligent slaves.
I was able to get a couple RS-232/485 converters, the Black Box ICD100A to be exact. After setting everything up and loading a simple edited program (Siemens actually publishes an example program under the name 20987910_BaseComm_Islaves_CODE_v10) I am still getting the "System Fault" and "Bus Fault" LEDs on each of the PLC processors. The problem now is that I am trying to find out if the concept itself is even possible, or if it is, where along the link the problem is. Let me give a quick diagram to show the total connection:
PLC-T--PBUSCABLE--T-RS485/RS232--RAD )) REP (( RAD--RS232/RS485-T--PBUSCABLE--T-PLC
LEGEND
PLC= S7-315
PBUSCABLE= Purple Profibus Cable, 2 conductor (green/red)
RS485/RS232= The ICD100A converter
RAD= MDS 9710A radio
REP= Repeater
T= A place where a terminating resistor has been put in the "on position"... for the PLC side, this is the Profibus connector... for the Converters, this is Dip Switch 5. Is termination a requirement of the electrical characteristics of the cable or the protocol of Profibus?
Other notes... the only thing that we have confirmed so far is that the radios successfully can poll one another using their proprietary software. Outside of that "box" we are not quite sure where to start.
If anyone would like to know anything else, I would be happy to provide it. Does anyone have any tips on this one? Much appreciated,
Ryan
I am working on a project in which I kind of have to "use the resources at my disposal as best and cheaply as possible." I need some help troubleshooting the system.
The situation is as follows... I have a master site, repeater, and remote site. The master and remotes both have S7 315-2 DP (315-2AF03-0AB0 / V1.2) PLCs, as well as MDS 9710A Licensed Radios. The repeater is an MDS of some sort (I have yet to see it).
What I would like to do is be able to poll the PLC at the remote site using the built-in Profibus ports on the PLCs. There is no additional Profibus hardware at my disposal. Speed is not really an issue here, 9600 baud is acceptable.
If these PLCs were next to each other (but same concept applied), it seems like the method would be to use I_PUT and I_GET instructions. At least this is what I have gathered from Hans Bergers' books and the use of intelligent slaves.
I was able to get a couple RS-232/485 converters, the Black Box ICD100A to be exact. After setting everything up and loading a simple edited program (Siemens actually publishes an example program under the name 20987910_BaseComm_Islaves_CODE_v10) I am still getting the "System Fault" and "Bus Fault" LEDs on each of the PLC processors. The problem now is that I am trying to find out if the concept itself is even possible, or if it is, where along the link the problem is. Let me give a quick diagram to show the total connection:
PLC-T--PBUSCABLE--T-RS485/RS232--RAD )) REP (( RAD--RS232/RS485-T--PBUSCABLE--T-PLC
LEGEND
PLC= S7-315
PBUSCABLE= Purple Profibus Cable, 2 conductor (green/red)
RS485/RS232= The ICD100A converter
RAD= MDS 9710A radio
REP= Repeater
T= A place where a terminating resistor has been put in the "on position"... for the PLC side, this is the Profibus connector... for the Converters, this is Dip Switch 5. Is termination a requirement of the electrical characteristics of the cable or the protocol of Profibus?
Other notes... the only thing that we have confirmed so far is that the radios successfully can poll one another using their proprietary software. Outside of that "box" we are not quite sure where to start.
If anyone would like to know anything else, I would be happy to provide it. Does anyone have any tips on this one? Much appreciated,
Ryan
