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James;
Im logging to the SD card. Logging Interval: No Wait
It all works well, Im able to collect data and transfer to the phone w/Bluetooth and to my PC using email or by moving the SD card. Very nice!
My issue is the sample rate appears to be 12 per second based on the UTC data time stamps. Im graphing shock displacement data from a string pot on a race car and 12Hz is a little slow. 30 to 100Hz would be great.
As I understand the Moshi sample rate and buffer depth only affect the display not logging rate.
Am I correct that 11Hz is my max log rate?
Thanks
Dan AllfordPCB: 007
ASM: 000
LOT: 00000
FW: 1477971088
CH1: AMPS 10A
CH2: OHMS 10kO
SMPL: 0032 8000Hz
UTC TIME SEC CH1 AMPS DC CH2 OHMS DC
1522790202 1.61E-03 4.88E+03
1522790202 8.94E-05 4.88E+03
1522790202 -5.81E-04 4.88E+03
1522790202 -2.09E-04 4.88E+03
1522790203 -2.46E-04 4.88E+03
1522790203 -2.83E-04 4.88E+03
1522790203 -6.56E-04 4.88E+03
1522790203 -2.46E-04 4.88E+03
1522790203 -3.95E-04 4.88E+03
1522790203 -9.16E-04 4.88E+03
1522790203 -3.95E-04 4.88E+03
1522790203 2.01E-04 4.88E+03
1522790203 -9.69E-05 4.88E+03
1522790203 -3.95E-04 4.88E+03
1522790203 -8.05E-04 4.88E+03
1522790203 -1.34E-04 4.88E+03
1522790204 -5.44E-04 4.88E+03
1522790204 -2.09E-04 4.88E+03In older posts I have found people getting 30hz SD card log rates which would be enough for me.
Ive found that low sample rates reduce the log rates. So Ive played with both sample rates and buffer depth. But I cant seem to get more than 12 logs per second.
Dan
Hi Daniel,
The sample rate and buffer depth do affect the logging rate, so I recommend raising the sampling rate if you want to log data faster.
However the other constraint is the amount of time it actually takes to log to the SD card, which unfortunately varies from card to card. So to push it as fast as it can go, I recommend setting your sampling rate to 2000Hz, buffer depth 32, logging with no wait between readings. If this does not give you a satisfactory logging interval, I suggest swapping out the SD card for one of lower capacity (I’ve found them to be quicker in the Mooshimeter, not 100% sure why).
~James
Thanks for the response. All I need is a small gain so Im optimistic.
Report to follow.Dan
I tried 2000hz sample and 32 depth with a 8gb (smaller) SD card. My SD card logging rate remained at 12 hz. I will install it on the race car and see if I have sufficient data.
Dan
Hi,
Just received the meter.
Any recommendations for SD card make and model to maximise logging frequency?Thanks
Riccardo
