User Manual

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Siemens Room Temperature Controllers N3067en
Building Technologies 2014-04-04
Control sequences
Used in conjunction with a valve, either for heating / cooling with changeover, heating
only or cooling only.
Used in conjunction with a 1-stage compressor for cooling only or heating only.
Heating mode Cooling mode
T[°C] Room temperature SDH Switching differential “Heating”
W Room temperature setpoint SDC Switching differential “Cooling”
Y11 Control output “Valve” or “Compressor”
The valve or compressor receives the OPEN command via control output Y11 when
1. the acquired room temperature lies by half the switching differential below the
setpoint (heating mode) or above the setpoint (cooling mode), and
2. control output Y11 was not energized for more than the “Minimum output off time”
(factory setting 1 minute, adjustable via parameter P16)
The valve or compressor receives the CLOSE command via control output Y11 when
1. the acquired room temperature lies by half the switching differential above the
setpoint (heating mode) or below the setpoint (cooling mode), and
2. control output Y11 was energized for more than the “Minimum output on time”;
(factory setting 1 minute, adjustable by parameter P15)
When pressing the heating / cooling changeover button
, the controller will change
from heating to cooling, or vice versa.
If the controller was set to ”Cooling only” or ”Heating only”, changeover will not be
possible (parameter P22, factory setting ”manual changeover”), instead NOP will flash
on the display, indicating continuous cooling or heating is set respectively.
The minimum output on time and off time of Y11 can be adjusted from 1…10 minutes
via parameters P15 and P16. Factory setting is 1 minute. In this case, any readjustment
of the setpoint or of heating / cooling mode changeover will be used immediately for
computing the output status and output Y11 may not hold the minimum on / off time of
1 minute.
If parameter P15 or P16 is set to a level above 1 minute, the minimum on / off time of
Y11 will be maintained as set, even if the setpoint or changeover mode has been
readjusted.
Water-based fan coil
application
Compressor based
application
ON
OFF
Heating / cooling
mode
Minimum output
on time / off time Y11