My SCADA/HMI on my PC has Modbus and the Gateway has Modbus, can I send my alarms from the SCADA/HMI to the Gateway?
Yes. But, since both the SCADA/HMI and the Gateway are Modbus RTU masters, they cannot talk directly.
Raco has a software package that can be put on you PC that creates a table that acts like a Modbus RTU Slave to other RTU Masters.
Contact Raco Sales for the Cost.