This question was originally posted on the HVAC-Talk forum by T87F

I have a "S4 Open: BACnet-N2 Router" working at a school. They had a power failure for about two hours over the weekend. The S4 router lost its IP address settings, it reverted back to the default settings. I reset the IP address and it works fine now. I wonder why the S4 router lost its custom IP address after a power failure. I will most likely add a UPS for this router in the future.

Response:

You can contact us any time that you need support. The UPS is always a good idea as an additional precaution. Without knowing the details here is the most likely scenario of what happened. The S4 Open Appliances are hosted on an industrial PC running Windows CE.CE runs in memory after it is booted from the CF card. This includes the registry image. If you change any system parameters you need to explicitly save the registry to the CF using /Start/Programs/Advantech/Registry Saver. If the system is rebooted for any reason the new information will then be read from the CF card.

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