This article provides a summary of steps needed to configure a Modbus Slave Outstation in Geo SCADA. This functionality allows a Geo SCADA system to be polled by Modbus masters such as RTUs, another Geo SCADA system or third party SCADA applications.
For simplicity, the master in this example is going to be another Geo SCADA application via a TCP connection. The example is not going to focus on how a master outstation is to be created and configured. The Geo SCADA installer comes with a detailed video guide on how master communication may be set up.
At first, a Modbus Slave Channel object needs to be created. This object may be found in Create New > Modbus Slave > Channel.
The slave channel needs to use the TCP port the master is configured for.
Once the Modbus Slave Channel is configured, a Modbus Slave Source needs to be created. It may be found in Create New > Modbus Slave > Source. The Slave Source needs to be pointing to the newly created Modbus Slave Channel and have a unique Modbus Address.
Next is to associate certain data points within the Geo SCADA application to the Modbus Slave source in order for the master to poll them. This is done by using Value Maps.
In this example, an Internal Digital Point named DP will be associated with a Discrete point and an Internal Analog Point named AP will be associated with a Holding Register.
Create a BIT Value Map ( do not confuse with FILTERED BIT Value Map) for DP and configure as follows:
Create a WORD Value Map ( do not confuse with FILTERED WORD Value Map) for AP and configure as follows:
In configuration of the Source object, attach the BIT Value Map to the Discrete Map and the WORD Value Map to the Holding Register Map.
At this point, the slave functionality should be completed and the Geo SCADA application can be polled by a Modbus master.
In the master configuration, the Modbus Master Outstation needs to be pointed to the Slave Outstation as follows:
The communication settings need to be configured to use the IP address of the machine hosting the slave Geo SCADA application and the port number configured in the Modbus Slave Source:
For simplicity, the master in this example is going to be another Geo SCADA application via a TCP connection. The example is not going to focus on how a master outstation is to be created and configured. The Geo SCADA installer comes with a detailed video guide on how master communication may be set up.
At first, a Modbus Slave Channel object needs to be created. This object may be found in Create New > Modbus Slave > Channel.
The slave channel needs to use the TCP port the master is configured for.
Once the Modbus Slave Channel is configured, a Modbus Slave Source needs to be created. It may be found in Create New > Modbus Slave > Source. The Slave Source needs to be pointing to the newly created Modbus Slave Channel and have a unique Modbus Address.
Next is to associate certain data points within the Geo SCADA application to the Modbus Slave source in order for the master to poll them. This is done by using Value Maps.
In this example, an Internal Digital Point named DP will be associated with a Discrete point and an Internal Analog Point named AP will be associated with a Holding Register.
Create a BIT Value Map ( do not confuse with FILTERED BIT Value Map) for DP and configure as follows:
Create a WORD Value Map ( do not confuse with FILTERED WORD Value Map) for AP and configure as follows:
In configuration of the Source object, attach the BIT Value Map to the Discrete Map and the WORD Value Map to the Holding Register Map.
At this point, the slave functionality should be completed and the Geo SCADA application can be polled by a Modbus master.
In the master configuration, the Modbus Master Outstation needs to be pointed to the Slave Outstation as follows:
The communication settings need to be configured to use the IP address of the machine hosting the slave Geo SCADA application and the port number configured in the Modbus Slave Source: