3 Detailed checklist
Checklist
Article ID: 109745536, V2.0, 05/2022
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3.12.3
WLAN iPCF
Menu path
You can find this information in IWLAN devices in the following menu:
"iFeatures > iPCF".
Recommendation
•
Use deterministic "iPCF" if you wish to transmit time-critical data
such as PROFINET over the wireless link.
•
Use "iPCF" together with IEEE 802.11a (not IEEE 802.11n) for a more stable
connection.
Note
"Standard DCF" cannot guarantee fixed transmission times and is therefore not
deterministic.
Note
"iPCF" is proprietary on SCALANCE devices and cannot be used with access
points or clients from third-party vendors.
3.13
Configuration
3.13.1
Storage information with MSPS devices
The devices save their configuration automatically in parallel:
•
Immediately after modification, in volatile RAM
•
With a 60-second delay after the modification, permanently in the flash storage
(and C-PLUG where applicable)
The goal is to minimize write access to the flash while the user is making changes.
After each change in the WBM, the following message will appear in the upper half
of the screen:
"Changes will be saved automatically in <xy> seconds. Press "Write Startup
Config" to save immediately".
Note
The change you made on the SCALANCE device is active immediately and has
been applied.
There is no reason to use "Write Startup Config" after each change. This way of
working runs contrary to the underlying idea, and is not necessary. The same
applies when restarting the SCALANCE device.
Only use "Write Startup Config" to save explicitly in the following cases:
•
If the device's power supply will be disconnected, otherwise causing the
changes from the last minute to be lost.
•
In trial mode (see
chapter 3.13.4
