User Manual

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Siemens QAX84.1/PPS2 – Flush-mounting room unit with PPS2 interface CA2N1649en_04
Building Technologies 2015-12-23
Operating notes
During commissioning and operation, the LCD panel displays error messages:
Display Description
Type of
error
C: No communication with controller for over 64 s
02: Firmware version (e.g. Version 2.0)
D
Room temperature sensor outside range 0 … 40 °C S
Controller has not yet added the room unit to its list of mem-
bers (during controller start-up)
D
Controller does not recognize room unit type D
Initial value, after room unit is switched on and before a con-
troller has sent a value.
S
Controller has not transmitted a valid temperature value S
S Static error: The error display remains valid until the error has been cleared.
D Dynamic error: For 5 s after its occurrence, the error is displayed instead of the room temperature.
The display then reverts to normal.
If the error persists, it can be displayed again by pressing the + or – button. Pressing the button
again implements a setpoint adjustment.
All other error codes indicate a hardware error.
Technical data
Supply voltage
Operating voltage range
DC 12 ... 15 V
The device receives its power via the PPS2 interface from the connected room controller
Power consumption (controller)
Max. 0.10 VA
Operating data
Temperature sensor
Measuring element
NTC resistance sensor
Measuring range
0 ... 40 °C
Response time
≤ 14 min
Measuring accuracy (5 … 30 °C)
± 0.5 K
Measuring accuracy (25 °C)
± 0.25 K
Setpoint correction
Correction range
(defined by controller)
Max.
± 10 K (basic setting ± 3 K)
Accuracy over full correction range
10 %
Display
Type
LCD
Functions displayed
–
Room temperature
–
Setpoint adjustment
–
Control mode ( / Auto)
–
Manually selected fan speed
–
Control sequence
– Type of error
Ports/interfaces
Type of port between controller and room unit
PPS2 (point-to-point interface, V 2)
Baud rate
4.8 kbps