I am looking into purchasing a data logger that will collect voltage,
amperage with a time scale.
Below is a sample of the data and a summary to be generated above the
data. I have some problems with how I can have a msexcel spreadsheet
automatically calculate averages and total times for each zone.
I would like a summary for many separate zones with a dozen or so
sessions that have recording to last from 10 to 100 seconds within
each session and automatically disregard calculating any values in
column C that are <30 & all rows in column B that have been
disregarded in column C.
Averaging for volts and amps will include all readings within each
zone.
To calculate time, I would like to calculate the difference between
when the amps go above 30 & the time when the amps drop below 30 + the
time one row down.

Formulas
In A2    =(A11-A9)+(A15-A13)+(A20-A15)
In B2    =AVERAGE(B9:B10,B13:B15,B18:B19)
In C2    =AVERAGE(C9:C10,C13:C15,C18:C19)
In A3    =(A24-A22)+(A29-A26)
In B3    =AVERAGE(B22:B23,B26:B28)
In C3    =AVERAGE(C22:C23,C26:C28)

    A    B    C    D
1    total time    avg volts    avg amps    total zone
2    00:00:54    25.3    122    b
3    00:00:30    25.0    125    f
4
5
6
7
8    time    volts    amps    zone
9    13:30:12    24.9    131    b
10    13:30:18    25.3    124    b
11    13:30:24    39.4    12    b
12    13:30:30    38.4    9    b
13    13:30:36    26.3    130    b
14    13:30:42    24.9    114    b
15    13:30:48    25.3    125    b
16    13:30:54    39.4    2    b
17    13:31:00    38.4    8    b
18    13:31:06    25.2    111    b
19    13:31:12    25.1    117    b
20    13:31:18    39.4    3    b
21    13:31:24    38.4    13    b
22    13:31:30    25.1    125    f
23    13:31:36    25    131    f
24    13:31:42    38.4    7    f
25    13:31:48    37.6    11    f
26    13:31:54    25    124    f
27    13:32:00    24.9    130    f
28    13:32:06    24.8    114    f
29    13:32:12    37.6    11    f

Can anyone help me with this? And an I on the right track?
Can this be accomplished without VBA? (as I have no success with it in
the past)
Thank you for your consideration.