V430 and remote Access via two Enfora GSM modems

[vmencin]

Hi

 

I have V430-J-T2 and two GSM modems Enfora (GSM-KIT-41J). I would like to remote access operands, data tables,... from PLC.

 

Both modems are initialized properly, on PLC SB80 = 1 (modem initiailized on COM1). But any remote access failed.

 

Also COM port is properly initialized in ladder. But when I dial there is always either "Dial timeout exceeded" or "No carrier". SIM cards are enabled for GPRS data transmission.

 

One more thing - in Help there is written that Enhanced Vision (like V430) should have baudrate = 57600. But in that case there is never succesful PLC side modem initialization. Only in case that baudrate is 9600 initialization of PLC modem is succesful.

 

PLC OS is up-to-date.

 

Can you prepare an example that remote access with such hardware configuration is working.

[Walkerok]

A couple of things that might help (or maybe not).

 

When connecting Vision or Enhanced vision controllers to a modem you can never have anything different than 9600.  The modem is able to be faster and the PLC is able to be faster, but the behind the scenes programming in Visilogic willnever give a successful connection at anything other than 9600.

 

On your modems connections to cellular service.  The Enfora modems are only capable of 2G service.  Depending on where you are 2 G service may not be available.  2G service will be gone nationwide in the USA in 2017 from all carriers and At&T has been dropping 2G service early in several location in the USA.  Check your SIM card carrier and thier coverage maps to be sure that 2G service even exists where you are trying to use the modem.

 

Thanks

Keith

[vmencin]

Thanks Keith

 

I have checked SIM cards carrier. They are both 2G.

 

But there is some progress - in fact what helps was the fact that I installed both SIM cards from the same provider.

 

But to download 5000 records in Data Tables at 9600 baudrate it takes more than 12 minutes.

 

How to solve this?

 

You can imagine how long would it take to download new firmware from PC to PLC via two GSM modems at 9600.

 

Do you have any solution?

 

Regards

[Walkerok]

This is one of those multiple possible solution questions, but because of the size of data you want to send you are pretty well limited using the modem to Unitronics solution.

 

I am not sure that you will like the answer very much, but to send a large quantity of data what we have done in the past is to make an ethernet connection with an "Embeded arm" controller sending an email with the file you want to transmit to the embeded arm product (you have to program that to be an email server) and then used it to make the connection with the modem since it will allow a full speed connection to the modem up to the maximum the enfora will allow.

 

You can use a celular router directly (again using an ethernet connection) but the Unitronics will perform poorly unless you have a 3G or 4G connection.  See Older Post from Jweav2223 that does this router method.  On the plus side the method used in that post has the benefit of being low cost.

 

Thanks

Keith

 

http://forum.unitronics.com/index.php?/topic/2692-ethernetcellular-commnication-ios-app/