Section 4 error messages, 1 gsm/gprs, 2 vpn tunnel – Hach-Lange SC 1000 Controller Enhanced Communications User Manual
Page 41: 3 modbus tcp, 1 gsm/gprs 4.2 vpn tunnel 4.3 modbus tcp, Er also to

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Section 4
Error messages
4.1 GSM/GPRS
See GSM error messages in the sc1000 controller manual.
There are no specific status messages for GPRS.
4.2 VPN tunnel
There are several status messages associated with establishing the VPN tunnel
connection. These are displayed under SYSTEM SETUP>BROWSER ACCESS>VPN:
•
OFF: The OpenVPN client is deactivated
•
LINK CONNECTION : The OpenVPN client is attempting to establish a connection to
the server.
•
CONNECTION: A connection to the server has been established.
•
INTERRUPTED: The connection to the server has been interrupted. This status is
displayed if the Internet connection is disrupted, e.g. the Ethernet cable is removed or
the GPRS connection is terminated. The connection is automatically established
again once the communication error has been resolved.
4.3 Modbus TCP
If an error occurs, the Modbus TCP server returns corresponding exception codes to the
querying client (
).
The last exception code returned to each connected client is displayed in the SYSTEM
SETUP>MODBUS TCP>STATUS menu.
SYSTEM SETUP
BROWSER ACCESS
VPN
SYSTEM SETUP
MODBUS TCP
STATUS
Table 4 Modbus exception codes in accordance with Modbus specification
Exception code
Designation
01
Illegal Function
02
Illegal Data Address
03
Illegal Data Value
04
Illegal Response Length
05
Acknowledge
06
Slave Device Busy
07
Negative Acknowledge
08
Memory Parity Error
10
Gateway Path Unavailable
11
Gateway Target Device Failed to Respond