C
Recommended Wireless Network
Practices
Follow all recommended practices to ensure highest data reliability. Deviation from these
best practices may require device repeaters in the network to maintain 99 percent data
reliability. Follow these guidelines to achieve the best possible Emerson Wireless Network:
1. Scope each wireless network field to a single process unit.
2. Minimize the number of hops to the Gateway to reduce latency. Contain a
minimum of five wireless instruments within effective range of the Emerson
Wireless Gateway.
3. Have at least three devices with potential communication paths. For stronger
performance, increase the required number of wireless neighbor devices to four or
five. This increases the number of potential paths and optimizes network
performance.
4. Have 25 percent of wireless instruments in the network within range of Emerson
Wireless Gateway. Other enhancing modifications include creating a higher
percentage of devices within effective range of the Gateway to 35 percent or more.
This clusters more devices around the gateway and ensures fewer hops and more
bandwidth available to WirelessHART
®
devices with fast scan rates.
5. Minimize the path distance from the gateway. For better performance, the path is
typically within range of one or two hops. This will utilize path redundancy and
create very short transit times.
6. Determine effective range by type of process unit and density of the infrastructure
surrounding the network.
C.1
Effective range
Heavy Obstruction: 100 ft. (30 m)–Typical heavy density plant environment; a truck or
equipment cannot be driven through this. Medium Obstruction: 250 ft. (76 m)–Typical
light process areas; lots of space between equipment and infrastructure. Light
Obstruction: 500 ft. (152 m)–Typical of tank farms; despite tanks being big obstructions
themselves, lots of space between and above makes for good RF propagation. Line of
Sight: 750 ft. (230 m)–No obstructions between WirelessHART
®
devices and devices
mounted a minimum of 6 ft. (2 m) above ground or obstructions.
For examples and complete explanations, refer to the IEC62591
Wireless
HART System
.
Reference Manual
Recommended Wireless Network Practices
00809-0100-4708
June 2022
Rosemount 708 Wireless Acoustic Transmitter Reference Manual
47
