Hi guys,

We have used a DT80 to collect data sent by serial sensor, it works at 10 Hz at least. There is no problem when collect the data and save it in its internal memory.

The problem is when we set another schedule to copy all data from its internal memory to a USB disk which is connected all the time, the logger cannot keep up the the sensor's output and some data lost for some period.

Everything is fine when the disk copy job finishes, we are considering a DT800 as an alternative to the DT80, because it use a PC card. Does DT800 succeed in doing such job? Is there any data loss when inserting and ejecting the PC card?

It is pity we cannot do the test by ourselves because we are considering the plan and there is no DT800 at hand.

Regards,
Tony

I think the difference will be very minor.

The detail will vary depending on your serial sensor, string parsing and whatever else you have the logger doing, but in my opinion, Some reduction in sampling and logging speed during data transfer is inevitable.

If you are logging at a high rate on the DT800 you should stop logging before removing the PCMCIA card. Otherwise I believe you risk corrupting the file on the card. If you insert a card while the logger has been logging to internal memory (2 MB on the DT800) you will probably loose a small amount of data while the data is moved to the memory card.

Downside of designing to do everything fairly well instead of doing very little, but doing it exceptional well. DT loggers are fantastic as the 'do everything logger', but you can run into limitations like this.

Thanks a lot for the suggestion, your experience does help us!