●
Use the LCD console to run the Network Status test. This will attempt a number of things including a ping query to the
gateway address. If the AcquiSuite can ping an external machine such as a gateway, the ethernet port is most likely
connected properly. If the AcquiSuite does not use a gateway, try adding a gateway address, and make it the address of
your computer.
System Options
Status
The system status page shows the current memory and flash disk utilization values, system up-time, and load average. Also
included on this page are two buttons for
Reboot
and
Shutdown
. It is important to use the shutdown option prior to
removing power from the AcquiSuite. The LCD console will report the reboot or shutdown status.
Processes
The system process table is shown in both tree and tabular formats. The process list is useful when contacting Obvius
technical support.
Date and Time
The AcquiSuite keeps time using UTC or Universal time. All log files are recorded in UTC time as well. Timestamps shown
on the AcquiSuite local configuration pages are converted to local time for the convenience of the installer. The date/time
configuration page provides the following options
Date/time
in UTC and Local time.
Date/time
dropdown menus to select the current (Local) time manually.
Timezone
: a drop down list of the supported timezones.
Time sync protocol:
Select NTP or Rdate. Most Linux/Unix systems provide rdate, however many provide NTP as well.
Windows domain servers can also provide NTP. If possible use NTP as it is a more robust protocol.
Time Server:
Specify the dns name or ip address of your time server. The default “time.obvius.com” can be used if the
AcquiSuite has a connection to the Internet. The AcquiSuite will attempt to synchronize time with the time server every time
an upload session. This will ensure that the clock is checked and adjusted at a minimum of once per day. Typically, the
synchronization will align the clock to -1 second of the internet time source or atomic clock. You may need to
verify if your firewall will allow NTP or Rdate packets to pass through. Generally, it is better to use a local time server if
possible. The time server time.obvius.com supports both NTP and Rdate time protocols. If you use a GSM connected
system, you will probably need to use Rdate. NTP is blocked by many cellular service carriers.
Universal Time Is Your Friend
Log data is stored in UTC time. This allows data collection services such as BMO to collect data from multiple sites in
different time zones. If you are operating your own database system to store log data from the AcquiSuite, it is best to store
the data in UTC time in the database as well, and only convert it to local time when generating the final report or graph for
the user.
If you store data in Local time, you will have the following issues.
1) Local time is relative. Is Local the time where the AcquiSuite exists, or Local to where the data is stored. If local to the
AcquiSuite, you must shift each AcquiSuite data set depending on its location.
2) There are about 11 time zones in the US. Some observe DST, others do not. These include Alaska, Aleutian, Arizona,
Central, Eastern, Hawaii, Indiana, Michigan, Mountain, Pacific, and Samoa.
3) When converting to local time, there will be one hour of overlapping data in the fall when the time is adjusted for
Daylight Savings time. ie, log entries run 12:45, 1:00, 1:15, 1:30, 1:45, 1:00, 1:15, 1:30, 1:45, 2:00am. This will prevent
you from sorting your data by time in your database.
4) In the spring, you will have a gap in the data from 1:59 to 3:00am. This can cause problems if you are calculating
demand values based on consumption.
5) Converting Local time to any other timezone usually involves converting it to UTC first.
Using UTC time solves these problems elegantly. The best practice is to store data in the database in UTC format and then
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A8810 AcquiSuite – Data Acquisition Server
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