[Mogster]

I have a 5 year old Davis data logger in my VP2 console. When I download it it says it holds 500 or so records, obviously the time that takes to fill depends on your set recording interval.

The new ones seem to hold more records than mine, 2500 I think is advertised. Are the new data loggers larger than my old one? It would make sense as flash memory is so cheap now and not to put too fine a point on it Davis loggers are rather pricey.

[Dave K]

Mogster, on 29 April 2012 - 12:34, said:

I have a 5 year old Davis data logger in my VP2 console. When I download it it says it holds 500 or so records, obviously the time that takes to fill depends on your set recording interval.

The new ones seem to hold more records than mine, 2500 I think is advertised. Are the new data loggers larger than my old one? It would make sense as flash memory is so cheap now and not to put too fine a point on it Davis loggers are rather pricey.

I have a 6510 datalogger for my VP1 which I bought in 2004, like the current one it stores 2 650 records, which is 17 days of data at 10 minute intervals in my case. I'd be surprised if yours only stores a max of 500?

[Mogster]

I've probably got the same version as you Dave, it might be 500 or 600, I'd have to check the next time I download. Its certainly not 2500 though.

I do forget to download sometimes, which is annoying. Extra capacity would be good, although expensive.....

[Dave K]

Mogster, on 29 April 2012 - 13:02, said:

I've probably got the same version as you Dave, it might be 500 or 600, I'd have to check the next time I download. Its certainly not 2500 though.

I do forget to download sometimes, which is annoying. Extra capacity would be good, although expensive.....

The longest time I have actually gone away from home while I have had the VP1 & datalogger was 14 days, and it retained all that data at 10 minute intervals - and that with the extra sensors for Sol Rad and UV too. What is your logging interval set to? How many days data can you download max before it writes over the old data?

This is the blurb

Quote

Data Logger Archived Data
The Data Logger stores up to 2560 archive records (one 52-byte record per archive interval) for later transfer to your
computer. The archive records are stored in 128K of non-volatile memory; protecting the data even if the console
loses power. Maxima, minima, averages, and totals are taken over the archive interval.

The amount of disk space necessary for the data files depends on the archive interval. Each archive record in the
database is 88 bytes. Every day in the database has an additional two records totalling 176 bytes that store daily
summary information. A database containing data stored at a 30-minute archive interval requires approximately 4400
bytes of disk space per day or 132 KB of disk space per month. The file size changes in a linear fashion depending
on the archive interval. For example, data stored at a one-minute interval requires approximately 3.9 MB a month
while the data stored at a two-hour interval requires approximately 33 KB a month.

This from an online doc but my own one printed in 2003 says the same.

This post has been edited by Big Dave's Gusset: 29 April 2012 - 13:19

[prodata]

All Davis VP data loggers, ever since they were first introduced in 2001 was it, will store 2560 records - they've always been fitted with the same 128K memory. But I think you're confusing pages and records. The 2560 records are organised as 512 'pages' and IIRC the download dialogue shows the number of pages not the number of records. So when the logger is totally full it will show 512 _pages_ as available for download.

If you're consistently seeing the 512 figure then either you're leaving it too long between downloads (for the archive interval currently set) or there's something amiss with your configuration.

The only exception to the logger memory size would be the newish Envoy8X console which can store far more data, though this is a property of the 8X console and not the logger fitted.

[Mogster]

Yeah that's it thanks. If I forget to download I see 512 pages, I try to avoid that. At 30 minute intervals the logger seems to hold about 6 weeks of data.
I wish the console flagged when the logger's full.

Hmmm 128K is almost medieval in 2012.

[belfryboy]

Mogster, on 29 April 2012 - 13:53, said:

Yeah that's it thanks. If I forget to download I see 512 pages, I try to avoid that. At 30 minute intervals the logger seems to hold about 6 weeks of data.
I wish the console flagged when the logger's full.

Hmmm 128K is almost medieval in 2012.

I would suggest that this is due to available size of Dataflash at the time of design. The firmware only seems to recognise 128k of memory and nothing else, and I suspect the if the console firmware was re-written for larger Dataflash chips then the older loggers would stop working, resulting in a lot of very unhappy Davis customers.