User Guide

Trends

Trend Data Storage

173

Siemens User Guide Version 2.1

A6V10415471_en_a_21

Building Technologies 2015-07-15

Change to Daylight Savings Time

 Date/time data is saved in UTC format. Entries are in double for one hour when

setting back to normal time. In this case, the curve is displayed using both

values. When switching to daylight savings times, no value is displayed in this

hour and the displayed line is straight between the two measured values.

 A system message Anomaly is generated when changing times that must be

acknowledged.

Application Examples for Online or Offline Trend

Online Trend: You can create the online trend if the room temperature is too low

and record data for specified period and analyze measured values in a trend curve

directly on the management station.

Offline Trend: Assign the outside temperature to the Trendlog object in the

automation station if you want to calculate energy consumption and need the

outside air temperature series for measured values. You can then manually or

automatically (periodically) upload the recorded temperature data to store in the

management station.