43
<DATA LOG> Page
The longer the sampling time, the fewer the improvement of accuracy and the fewer the data
logged.
Usually, when sampling rate is set to 500ms or 1s, can ensure the best accuracy and faster
response.
The shorter the sampling time, the faster the buffer inside the instrument will use up, the
following list is the logging time of internal RAM buffer (2,000 thousand groups data for each
channel) of 10 channels after all is turned on. If exceeding MAX recording time, the previous
data will be covered.
Table 9-1 Sampling rate and internal buffer logging time
Sampling Rate
Buffer’s MAX Logging Time
10ms
5.56 hours
20ms
11.12 hours
50ms
27.78 hours
(
1.1 days
)
100ms
55.56 hours
(
2.3 days
)
200ms
111.11 hours
(
4.6 days
)
500ms
11.5 days
1s
23 days
2s
46 days
5s
115 days
10s
231 days
20s
1 year 97 days
1m
3 years 293 days
TIP
20,000 thousand groups data is available for internal buffer, and they are allocated to 10 channels, each
channel gets 2,000 thousand group data,
Internal buffer is high speed RAM, power failure will make data lose.
When sampling with high speed, accuracy will be low, to reach instrument’s technical specifications,
users can get this at higher than 1s sampling rate.
Steps of setting sampling rate:
Step 1
Enter <DATA LOG> page
Step 2
Under state of stopping data logging, touch screen or use cursor to select sampling [Rate] field;
Step 3
Touch functional field at right side of screen, click & select sampling rate value.
19 types of sampling rate is available for instrument:
10 ms
20 ms
50 ms
100 ms
200 ms
500 ms
1 s
2 s
5 s
10 s
20 s
30 s
1 m
2 m
5 m
10 m
20 m
30 m
1h
TIP
Sampling rate can only be set after data logging stops, it cannot be set during logging.
Under sampling rate of less than 50ms, due to limitation of storage speed of external disk, instrument
will only use binary format to save files to external memory, and will not be decided by the file format of
[Real-time Saving] in <SYSTEM CONFIG> page.
Due to the bottleneck of external disk’s speed, users cannot ignore the time of writing external disk in
the course of high-speed record, so the graph will nap for a while every time writing into external disk.
Under sampling rate of less than 100ms, saving data into external disk manually is recommended, don’t
insert disk during logging.
9.2
Horizontal Axis Gridding Setting
The larger the time of gridding setting, the more the sampling site one screen displays, the more
obvious the trend.
21 types of horizontal axis gridding setting are available for the instrument:
