How to estimate data acquisition storage requirements

[JohnMetcalf]

How can I estimate the size of my data files so I can implement the correct size data storage device (like an external USB hard drive) given;

Measurement type: Accelerometer transduced to voltage

Frequency Range: 0 to 800 Hz

Measurement Range: +/- 10 g

Channels: 12

Sample Rate: 1.652 kS/s

ADC: 24 bit

FSR: +/- 5V

Time: varies and can vary depending on the size of the storage space

Below is the setup I'm considering which is a cRIO 9030 with three NI 9234 c-modules.

Thanks for the pointers - John M

[crossrulz · Accepted solution]

How do you plan to store the data?

Let's assume TDMS, which will store the data a DBLs.  12 channels * 1.652k Samples/second * 8 bytes/sample = 158592 Bytes/second = 154.875kB/s.

[JohnMetcalf]

crossrulz -

TDMS is correct. Can you tell me why this matters for this problem, or point me to a reference?

Regardless of data acquisition equipment and instrumentation, will every sample contain 8 bytes?

Thank you for helping

Sincerely

-John M

[crossrulz]

If you are storing the data as text, that makes a huge difference.

A DBL (Double Precision floating point number) is 64 bits (8 bytes).  That is just what the data is.  You could also save the data as a SGL (Single Precision floating point number), which uses 4 bytes per sample.  That would use half the disk space, but will lose some resolution if calculations (like scales) are done on the data.