SSP Safety Simplifier, Руководство пользователя

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SSP North AB 30/08/2018 Manual V2f
84
13.10.4 Designing systems that communicate via radio
In general, to achieve the best possible radio quality there are three rules:
1. Every node in the system should have good radio connection to at least three other nodes in
the system
2. Every node should have good radio connection to the previous node (node 2 should hear
node 1, node 3 should hear node 2, etc)
3. Node 1 should have connection to the last node in the system.
For systems with 2, 3, or 4 nodes, each node should have a good radio connection to every other
node in the system.
To achieve a good radio connection between two given nodes, the nodes must be within a certain
range of each other. This range depends on walls and other obstructions.
13.10.4.1 Radio quality
For the system in Figure 13.3, a very good radio quality can be expected. All nodes are within range to
each other and hear each other directly. This means that no node in the system relies on repeated
information.
If a radio disturbance makes for example node 3 miss the information sent by node 1, it still has a
chance to hear the repeated information from node 2. This makes the system more resistant (but of
course not immune) to random disturbances, and thus more reliable.
Figure 13.3: An example of a system with good radio
quality. Blue circles indicate signal range, arrows indicate
direct radio contact. Note that the recommended distance
between nodes depend on walls and other obstructions
between the nodes.