Machines from different generations rarely speak the same fieldbus: one line runs Modbus RTU, another talks Modbus TCP, and the rest expose proprietary PLC links. V-BOX H series sits between that mix and the cloud, collecting, translating and forwarding without a PC in the loop.

Why does a gateway need three serial ports and three Ethernet ports?

Because the plant does not rewire itself for one protocol. COM1 handles RS232 or RS422/RS485 and COM2/COM3 add two more RS485 drops, so a machine with a servo drive, a VFD and a controller can be connected at once; three Ethernet ports let the gateway sit inline between the PLC network and the office LAN. Modbus RTU and Modbus TCP are native, and major PLC protocols are covered for free-tag reads, while Lua scripting handles logic that fixed protocol stacks cannot.

When does the 4G module earn its keep?

When the site has no IT network or the machine is mobile - an aggregate plant, a remote pump station, a skid that ships with the product. The H-4G option pushes the same data to the cloud over the mobile network, and the WiFi variant (H-WF) covers warehouses where cabling is impractical. With 128 MB Flash and RAM, 500 live points, 300 alarm points and 10,000 history points, the gateway keeps enough context locally that a cloud outage does not erase the data.