MGate 5111
Web Console Configuration
4-26
Fault Protection and Status Monitoring
Fault Protection
The Fault Protection function sends a predefined setting to field devices to prevent incorrect actions when the
upstream connection is lost. The MGate 5111 supports a Fault Protection function when selecting Modbus
RTU/ASCII master mode or Modbus TCP Client mode. You can configure the criteria used to determine what to
do when the write command is no longer received from the master side. For example, when a cable comes
loose accidentally, the most up-to-date write command from the master side will not be received by the
gateway. Hence, the slave device will use the latest command from the gateway, which is now out-of-date,
creating an inconsistency between the master and slave devices. To avoid this problem, the MGate 5111
supports options to determine which actions should be taken when the master’s side is disconnected from the
gateway.
Options
Description
Keep latest data
The gateway will write the same data to the slave
device.
Clear data to zero
The gateway will write zero values to the slave device.
User-define value
A user-defined value will be written to the slave device.
Status Monitoring
The
Status Monitoring
function provides status information of field devices when the MGate is being used as
a Modbus RTU/ASCII master or Modbus TCP client. If a slave device fails or a cable comes loose, generally the
gateway won’t be able to receive up-to-date data from the slave device. The out-of-date data will be stored in
the gateway’s memory and will be retrieved by the master device (e.g., PLC), which will not be aware that the
slave device is not providing up-to-date data.
The MGate 5111 allocates one bit of the gateway’s specified memory address to indicate the status of each
Modbus command as being normal or abnormal. If a command has run successfully, the status value will
continuously be 1. On the contrary, if a command has failed, the status will be set to 0. In this case, the master
device will be aware of the failure status of the slave device. Add PROFIBUS status input module in PROFIBUS
Slave Setting page. Max. modbus command is 128, so you can add 16 bytes input module to indicate all
Modbus command status.