Motor-operated valve (MOV) communication

It receives and reads data from the MOV based on the set communication configuration, such as device address, register, function code, baud rate, parity and other communication parameters. Once the ECU Advantech 1051 has received and processed the MOV data, communication to the InduSoft SCADA goes over a LAN/Ethernet network.

On the LAN line between the ECU and the SCADA there is also a LAN Arrester as network protection. The LAN Arrester protects against overvoltage or surges that can enter through the Ethernet cable, and so helps protect the Ethernet port on the ECU, the switch or network devices, and the SCADA computer.

It has a similar protective function to the SPD, but it is applied on the LAN/Ethernet line, while the SPD protects the RS-485 line. Overall, the MOV restoration signal path is: Flowserve Limitorque MOV → RS-485 → SPD → RS-485 → Advantech ECU-1051 → LAN Arrester → InduSoft SCADA.

On the SCADA side, the data received from the ECU is shown as tags used to monitor and control the MOV. The tags can show OPEN and CLOSE status, valve position, Local/Remote, thermal, torque and fault, and can send OPEN, CLOSE and STOP commands according to the system configuration.

With the SPD on the RS-485 side and the LAN Arrester on the Ethernet side, the MOV communication system has a protection layer on both main communication lines. The SPD protects communication from the field to the ECU, and the LAN Arrester protects the network line from the ECU to the SCADA.

Once all physical connections and communication settings were confirmed correct, a test was done: a command was sent from the SCADA, the MOV received it, and the MOV feedback was read back on the SCADA. This test is an important part of MOV restoration. It confirms that monitoring and control match the actual condition in the field.