Four kinds of wireless

PROFIBUS and PROFINET are involved in three of the four kinds of wireless. (Yes, wireless is not one monolithic thing: Wireless or Wireless.)

My take on the four kinds:

1. Long-distance like to RTUs
2. Process instrument networks like WirelessHART (PI cooperated with HART Communication Foundation and Fieldbus Foundation to standardize this: Simplified Wireless Communication)
3. Discrete sensor and actuator networks like PI’s FA WSAN
4. Backbone like PROFINET uses (WiFi and Bluetooth)

There is some confusion as to why we need a separate standard for discrete sensors and actuators – why can’t we use the process standard? I think the answer is mostly speed – discrete sensors and actuators need faster response times. But there are other different requirements, too, as this chart that we provided to Control Engineering shows (Sensor-actuator wireless industrial network technologies):

–Carl Henning