HI

I am doing a job at the moment, where we require 3 remote dataloggers, to provide continuous live data. I am wondering how do I use the internal modem as the modbus interface between the DT82EM and the SCADA/PLC,

I understand the DT82EM will have to have a fixed I.P. address attached to it, or else go in through a Dynamic DNS, but what i am wondering is,

1. Is the logger automatically set to have its registers queried through the modem? or does it have to be done similar to the Ethernet port where a line of code has to be put into the logger to get this working.

2. what is the line of code to do this, if needed.

I know the codes for the other ports from looking in the manual but I don't see anything for doing the above through the modem.

any help would be appreciated

with thanks

Conor

read the manual a bit better this time, it can be done and doesn't require any extra configuration,

good news then

Hi Connor4613,

Register address will have a corresponding Channel Variables number, i.e.: address 400001 will correspond to 1CV.
You can use a host name for replacing IP address.

You may need to set a specific APN to get public IP address from your phone provider,
otherwise you may only get local IP address* in which the connection can't be established if you are outside their network.

*local IP address starts with IP header of 10 (i.e.: 10.125.70.80)

The syntax to read 1CV (assuming the public IP address is 123.209.132.215) would be
4MODBUS(AD"123.209.132.215",R4:1)

At some point you may need to define different format using SETMODBUS syntax.

Best regards,
Rudy Gunawan

Thanks for that Rudy,

Does the datataker support a VPN,

the end user wants to use the VPN to connect to the logger to increase security.

with thanks

Conor

Hi Conor,

Internal modem of dataTaker does not support mobile VPN at this moment (we are still working on its firmware).
If you want to use mobile VPN, please use external modem (3G modem or 3G router).

Best regards,
Rudy Gunawan

Hi Rudy

Is there a setting in the datataker to change to get it to work with a Moxa interface over Modbus,

a PPP setting etc?

with thanks

Conor

Hi Conor,

dataTaker setting will depend on the choice of MODBUS communication and the position of DT in MODBUS network (Master/ Slave).

• MODBUS Master + MODBUS over SERIAL -> serial port setting
• MODBUS Master + MODBUS over TCP IP -> none
• MODBUS Slave + MODBUS over SERIAL -> serial port setting, slave address
• MODBUS Slave + MODBUS over TCP IP -> none

Best regards,
Rudy Gunawan

Hi Rudy

the datataker will be the modbus slave, with the Moxa being used on the plants network, while the Datataker is on a remote location, the Moxa will be using 3G/GPRS to communicate to the logger through its modem.

the information can be accessed correctly, if you go from the scada direct to the logger, but once you put the moxa in the middle, it stops working.

we are only working on the logger side, Schneider are doing the scada work.

so would you think its the logger that needs a bit more configuration or the Moxa?

with thanks

Conor

Hi Conor,

So you are using Moxa to make MODBUS call through TCP IP to 3G modem.

What is the Moxa model?

Is the modem connected to private network (IP address has a header of 10) or public network?
What is the header of your 3G IP address? (For security reason do not write complete IP address in this forum).

Best regards,
Rudy Gunawan

Hi Rudy

its a moxa one cell,

both units are using a public i.p. address, as the datataker is currently on a dyn.com web address.

the i.p. address of the moxa is 95.83.XX.XX.

with thanks

Conor

Hi Conor,

Can you give me a link to this Moxa model? I tried to google it without success.
If the modem creates a transparent connection to internet, it should be able to pass MODBUS request from your SCADA.

I will email you for further investigation.

Best regards,
Rudy Gunawan