how to use csv log file with relative values in Excel

[mcinque]

I have a device that produces a log file with only relative values (see attachment), example:

Code: [Select]

Vertical Scale,50000V 

Value
12.000,
12.000,
12.000,
12.000,
12.000,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
1614.0,
29527,
29527,
29527,
29527,
29527,
40265,
40265,
40265,
40265,
40265,
40265,
I don't know exactly how to use it in excel: I can create a graphic but I miss the relative scale so I see the samples but they are not correlated to a reference; do you have any advice how to use it (and why some manufacturers prefer to use relative scale instead absolute?)

[PA0PBZ]

If these are relative values they must be relative to something, if you can't find the 'something' the values have no meaning.

[Vtile]

So is that a tension per sample number shown in the csv-file ?

[mcinque]

If these are relative values they must be relative to something, if you can't find the 'something' the values have no meaning.

exactly.

So is that a tension per sample number shown in the csv-file ?

Should be the exact value recorded by the meter (Volts)

----------------

I discovered the values are NOT relative. It's the scale that changes during the measure.
So they are absolute but they become odd (without the separator) when the value goes up a certain limit.

Take this log for example. It's a quick measure up to 240VAC and then down to 0.

0.4790,<--- MAINS DISCONNECTED, 500mVAC
0.4790,
0.5330,
24229,<--- MAINS CONNECTED, OF COURSE 242.29VAC
24229,
24229,<--- START LOWERING VOLTAGE TO ZERO
63858,<--- 63.858VAC
63858,
16386,<--- 16.386VAC
16386,
42931,<---42.931VAC
42931,
42931,
58169,<---58.169VAC
58169,
32437,
14743,<---14.743VAC
14743,
25050,
10469,
0.5700,<--- ZERO

It seems impossible for me to understand "14743" is 14.747VAC instead 147.43VAC without knowing the measuring scenario behind, and this is of course something that a log file shouldn't do since it's designed to log unattended and for many hours.

It's me that I'm wrong in something?

EDIT: this seems dued to the autoscale function of the meter that changes automatically the recording scale of the log. The scale are 0-6V, 6-60V, 60-600V so that numbers has sense now. Putting the meter in manual mode will "fix" the issue.

In my opinion, the meter should NOT be allow datalogging in auto range or at least should put in manual automatically.

The values recorded has no sense without manual mode if the reading exits from the initial range.
Are the other multimeters with datalogging doing the same than this (allowing autoscale in datalogging mode)?