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Entry type: FAQ Entry ID: 51563241, Entry date: 07/25/2011

What should you watch out for when setting the time of day on the TIM modules with an integrated DCF77 radio clock receiver?

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On SINAUT ST7 TIM communication modules with an integrated DCF77 radio clock receiver, the maximum deviation of the DCF77 clock is 4 seconds per day. This value applies if the clock has been set at least once by DCF77 and if there is a failure in the contact to the transmitter (Mainflingen).

If the DCF antenna is not connected when the TIM module with integrated DCF77 radio clock receiver starts, the time of day is set to "invalid" internally.
If the time of day is now set on this TIM module, via a programming device for example, the time of day is validated as winter time, and the TIM module synchronizes the stations.
Winter time is the default setting when the time of day is set via the programming device.
When operating ST7cc or ST7sc by contrast, the time of day of the ST7cc or ST7sc in summer is always set to summer time. Enable the "Automatically adjust clock for daylight saving changes" function under "Date and Time" in the Windows Control Panel on your PC.

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