Starret DataSure, Руководство оператора

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DataSure™ Operators Manual 29 PT 6*****
This example shows that multiple paths in a mesh network provide alternative paths for data thus
spatially and temporally avoiding corruption from EMI.
Unlike mesh networks, daisy chain or point-to-point networks suffer from “single points of
failure”. See Figure 2. If one link in the chain is corrupted via EMI, then OTA transmission will
stop at that break in the “chain”.
Suffice it to say, if the wireless network is capable of supporting a mesh configuration, then
simply adding Routers to the system will make the system more robust.
However, data errors are not isolated to EMI. There are other environmental and user related
means to cause data errors. The well informed system installer and network administrator will be
able to choose the right system and remedy for certain kinds of data integrity problems.
In paper and pen data recording, it is immediately apparent that data has been recorded. By
looking at the paper, you can easily see what was recorded. Wired systems for data collection are
typically connected to a local device that displays the most recent reading. Some installations of
data collection have PC’s at each work cell or bench showing the data and trend lines for the
measurements in progress.
One of the key advantages of wireless data collection is freedom from the bench; host PC’s,
wires and the limitations of bringing a part for inspection to the tool.
Therefore, with wireless systems, data being recorded may not be immediately or readily visible.
Consider a shop floor operator with a wireless tool. When data is recorded by pressing a button
on the tool or data cable, the data shows up at the gateway/PC screen. If the PC is not located in
the immediate vicinity of where the data is taken, and often it is not, then the operator is unsure
data has been received. Some wireless data systems have no capability to alert the operator of the
tool that the data actually made it to the intended destination – here it is the PC/gateway.
Advanced systems for wireless data collection have indicators/enunciators on the data
transmission device itself, to show the operator the status of the system and the successful
transmission of data. In many systems, the EndNode is “unaware’ that the network or host PC
loses power, and therefore, data will not be recorded. However, if the endpoint has the ability to
Figure 2