Industrial IoT in a process plant. A process plant with three wireless networks: an instrument mesh, LoRaWAN tank gauges and a microwave hop.

Layers

Scenario

A process plant with three wireless networks: an instrument mesh, LoRaWAN tank gauges and a microwave hop.

01/05

EU868 LoRaWAN: 863–870 MHz · λ 35 cm · LPWAN, 1 % duty cycle · LoRa Alliance RP002-1.0.4

Network scenes

Industrial IoT in a process plant

Wireless instruments on the pipe racks and process units form a mesh to the control building, tank gauges report over LoRaWAN, and a microwave hop links the control building to the substation.

The place: Process plant

In this scene

Wireless instrument gateway

Gateway and network manager for the wireless field instruments, on the control-building roof, with the plant historian behind it. (IEC 62591 (WirelessHART), IEC 62734 (ISA100.11a))

Wireless pressure and temperature transmitters

Battery transmitters on the process units and racks, each a router for its neighbours: steel is everywhere, so the mesh finds paths around it. (IEC 62591, IEEE 802.15.4)

LoRaWAN gateway on the stack platform

Tank-level and corrosion sensors on the tank farm report to a gateway on the stack platform at 60 m. (LoRaWAN L2 1.0.4 (TS001-1.0.4), LoRa Alliance RP002-1.0.4)

Substation automation

Protection and control in the plant substation, linked to the control building by a licensed microwave hop. (IEC 61850, ITU-R F.595)

Computed for this scenario

18 GHz hop to the substation

0.35 km · 18 GHz

Worst clearance of F1

793 % (clear)

Knife-edge loss (P.526)

0.0 dB

Free-space loss (P.525)

108.4 dB

Received level

-12.7 dBm · margin 57.3 dB

Gateways in service

1 of 1

End devices served

12 of 12

Mean spreading factor

SF7.0

Mean time on air, 20 B

57 ms

SF12 ring radius

9.2 km

Uplinks an hour at SF12 under 1 % duty cycle

27

Mesh nodes reaching the sink

0 of 20

Longest route

—

Cut off

20

Scenarios

Normal

Every instrument reaches the gateway; the microwave hop clears its Fresnel zone F1.

Shutdown scaffolding

Scaffolding for a shutdown blocks two rack routers; their neighbours re-route. A new structure rises in the microwave path.

Tour transcript

1. A process plant with three wireless networks: an instrument mesh, LoRaWAN tank gauges and a microwave hop.
2. Instruments on the units and racks route through one another to the gateway on the control building.
3. Tank gauges report over LoRaWAN to a gateway on the stack platform.
4. The 18 GHz hop from the control building to the substation, with its Fresnel zone F1.
5. Shutdown scaffolding: two routers are blocked and a structure rises in the microwave path. Routes and the link budget are recomputed.

How the numbers are computed

Mesh links join instruments within 95 m; routes minimise the sum of 1 + (d / range)² per hop and are recomputed when routers fail. The microwave hop is judged on its profile over the plant: Fresnel zone F1 radius √(λ d1 d2 / d) (ITU-R P.530), 60 % clearance, single knife-edge loss J(v) (ITU-R P.526), free-space loss (ITU-R P.525) and 0.6 m dishes (ITU-R F.699 gain).