Modicon Quantum

I have very little experience with Modicon. I am trying to connect my laptop using proworx nxt and using the modbus port and cable but can not seem to connect to the CPU. When I do a device scan it shows no devices?

Have you used this laptop and Modbus cable to successfully connect to other 984 based PLC's in the past? When you try to attach to the PLC does the Modbus LED on Quantum briefly blink?

Here is a link concerning the Modbus cable wiring and a few other interesting notes...
http://www.plctalk.net/qanda/showthread.php?t=7502&page=2

Is your laptop running XP/Windows 7? We run ProWorx32 on XP Operating Systems without any problems, and I know Schneider Electric released a patch to run ProWorx32 on Windows 7 but we never tried it to connect to any PLC's.

Are you receiving Modbus Error Code 199 when you try to connect?

I have not used the laptop to connect to a different PLC We dont really have access to one but I may have the opportunity this coming week. The equipment is in our shop and has been stored for almost 4 years. The laptop runs XP. I do not have an RS232 port but I am pretty sure I have an adapter that actually works properly.The MODBUS light blinks green continuos. The error code that comes up is DIM Mode. I will check the link Thank you!

The message you are receiving indicates the controller is in DIM AWARENESS-which means it has lost its program and configuration and has reverted back to its 'out of the box' configuration (it basically doesn't know what it is)

(Going from memory since I'm not at work currently), this means it is Modbus address 1, 9600 baud, even parity, RTU (or at least I believe that is correct)

In this mode, you cannot simply goes 'online' with it. You must create and download a new configuration.

Ensure your ProWorx communication settings match the PLC settings.

Start by creating a new project and selecting the appropriate Quantum in the configuration (via the part number). Then, download this new configuration and you should be good to go!

Good luck!

ok I am not getting a blink from the modbus light when attaching the cable. I have tried two seperate RS 232 to usb adapters and I have a feeling we are not communicating to the PLC. I do not have access to a running Quantum. Any Ideas?

Greetings,

Post #3 (August 4th) indicated the 'Modbus light blinks green continuous'. However the recent reply states the Modbus light does not blink. What has changed?

Please ensure you are attaching your serial cable to the Modbus serial port and not trying to attach to the Modbus Plus port as this will produce an error message in ProWorx of 'Controller in Dim Awareness' (as indicated in a previous post)

I believe this PLC has a Modbus Plus port as well as a Modbus port (not sure as I am not at work). If the Modbus Plus port is not communicating to a MB+ device it will blink 3 times per second. It blinks 6 times per second when communicating to a MB+ device. The Modbus port LED does not illuminate until it has established communications with a Modbus device, ie your laptop.

I'm assuming the 'ready' LED is illuminated as well on your PLC, please confirm.

Might you be able to attach a schematic of the serial cable that you are using? (to ensure proper connections); and of course, your USB to serial adapters have successfully communicated to other devices in the past...yes?

Thank you!