Time of rain logging Discrepancy by one hour early

[PaulMy]

I still run CU1 with a Davis Envoy and USB logger. This is at 10-minute interval logging and on a Windows 8 PC.
I also run CMX with a WiFi-logger and a WLL. These are at 5-minute interval logging and this on a Windows 10 pc.

As I was comparing the Cumulus 24 hour rainfall since 8:00 am yesterday to today 8:00 am for comparing to my daily CoCoRaHS submission I noticed the time for the rain in CU1 was logged one hour ahead of my CMX logging. Usually I just look at the Yesterday and Today rain on the CU1 console but this time I also looked at the CMX Today and noticed a difference:

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CU1-Time CU1-Rain	MX-Time	 MX-Rain 
16:00			17:00	
16:05			17:05	
16:10	0.2 		17:10	 0.2 
16:15			17:15	 0.4 
16:20	0.4 		17:20	
16:25			17:25	 0.6 
16:30	0.6 		17:30	
16:35			17:35	
16:40	0.8 		17:40	 0.8 
16:45			17:45	 1.0 
16:50	1.0 		17:50	
16:55			17:55	 1.2 
17:00	1.2 		18:00	
17:05			18:05	 1.4 
17:10	1.6 		18:10	 1.6 
17:15			18:15	 1.8 
17:20	2.0 		18:20	 2.0 
17:25			18:25	 2.2 
17:30	2.4 		18:30	 2.4 
17:35			18:35	 2.6 
17:40	2.8 		18:40	 2.8 
17:45			18:45	 3.0 
17:50	3.2 		18:50	 3.2 
17:55			18:55	
18:00	3.4 		19:00	 3.4 

All the other data items seemed to be about the same for each logged time (some minor differences due to 5-minute vs 10-minute logging), just the rain out by one hour. From my recollection around supper time yesterday, CMX is logged correctly, and that is also confirmed by my WU and PWS Weather uploads. I checked a previous time of some ongoing rain and that time CU1 and CMX logging was the same times. The PC date and time is the same on both PCs.

I will watch for it during the next rain...

Enjoy,
Paul

[mcrossley]

Interesting

[PaulMy]

Update:
We had 0.6 mm of rain overnight and the CU1 logging times are the same as the CMX installs, so seems normal now.

Looking in the Diags files for the time when the one-hour early logging occurred all that it shows is the 10-minute interval entries like :

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Writing today.ini, Last UpdateTime = 05/10/2023 4:10:01 PM raindaystart = 789 rain counter = 789.200012207031

which is the first 0.2 mm rain, and similar logging every 10 minutes including new rain within each interval period.

I did also see in Diags on 06/10/2023 (which is the following day after the one-hour logging)

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06/10/2023 03:00:01.456 : Writing today.ini, Last UpdateTime = 06/10/2023 3:00:01 AM raindaystart = 797.4000024414063 rain counter = 799.799987792969
06/16/2023 04:00:25.601 : Windows TIMECHANGE message received
06/16/2023 04:00:25.608 : Windows TIMECHANGE message received
06/16/2023 04:00:25.610 : Windows TIMECHANGE message received

so no logging after 03:00:01 to 04:00:24 and continues normal after 04:00:25.

Then also the next day

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07/10/2023 03:00:17.000 : Windows TIMECHANGE message received

but there is then the usual every 10-minute logging of : Writing today.ini... at 03:10 and 03:20 and 03:30 and 03:40 and 03:50 and 04:00, etc.
We have not had a time change yet and still on daylight savings.

I also see that there have been a number of

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*** Data input appears to have stopped, restarting

and then, from the various Diags files, CU1 seems to be restarted which I wasn't aware of (forgotten that in Program Settings I have ticked to Restart if data stops).

The Diags also shows at

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 04:00:00 : VP2: Setting station clock

From those Diags messages the one-hour early logging could be a Windows or CU1 time issue, but that doesn't really make sense as it occurred the previous day and the time on the PC shows correct for our daylight savings time whenever I've looked at it. The automatic restart of CU1 may be the cause! I'll keep an eye on it.

Enjoy,
Paul