Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Data acquisition 03.10.2011
9 Data acquisition
9.1 Trend
9.1.1 Connections and application
The Trend function block is used for time-related recording of measured values.
It provides four independent trend channels.
A trend channel can record one measured value.
Two trend channels can be displayed per Trend view: Primary channel plus extra
channel as a reference.
It is possible to record signals from local inputs of the controller as well as room
temperatures and outside temperature via bus.
9.1.2 Views
The following illustration shows a 24-hour view on the operator unit with primary
trend curve and reference curve for an extra channel:
 The current 24-hour views (8 minutes, 8 hours, 24 hours) show the date and the
current value of the primary trend curve at the top
 The primary trend curve is shown as a solid line, the reference curve as a dotted
line
 The Y-axis label refers to the settings of the primary channel. If the Y-axes of the
two channels do not match, a warning symbol appears below the axis
Use the press-and-turn button on the operator unit to navigate between the four
different views:
 8-minute view: Sampling every 5 seconds, last 8 minutes
 8-hour view: Sampling every 5 minutes, last 8 hours
 24-hour view: Sampling every 15 minutes, current day
 Rolling over the last 6 days: Sampling every 15 minutes, last 6 days
Comment: The 24-hour view shows the last 6 days.
Purpose
Example
Contents
Change between views