5/11
Siemens
Temperature Controller RRV851
CE1N2725en
Building Technologies
27.08.2007
Commissioning notes
When powering up, the QAX850 will display all LCD icons for approximately 3 seconds,
and then the software version number for another 3 seconds. It will then revert to the
normal display. The time segments will be blinking if the time needs to be set. Set the
time of day as per Operating Instructions. There will be a delay before operation
commences due to polling of all values.
The user should not have access to the DIP switches or parameter settings. User
operation is via the QAX850 master room unit. For user operation details, refer to the
Operating Instructions included in the packaging box (document B2725en.01).
Generally, there is no need to recalibrate the sensor. However, the room temperature
displayed on the QAX850 LCD can be recalibrated if there is any discrepancy from the
actual temperature measured with a certified thermometer. The calibration function can
be accessed by pressing simultaneously the and buttons for 5 seconds. The
displayed value can then be adjusted via the same buttons in increments of 0.1 K. The
range is ±3 K.
The RRV851 controller is operational after the DIP switch settings have been made and
power is connected. Default parameter settings are based on the application selected
and may be modified if required. Refer to the list below. Parameters cannot be
accessed if the system is in Off mode. Refer to the Installation Instructions for setup
details and the Application Manual for default parameter values.
No. Parameter
Range
P00
Temperature scale
°C / F°
P01
Frost protection limit in Off mode
Off / 5…8 °C
P02
Overtemperature limit in Off mode
Off / 30…35 °C
P03
Min. off time delay
0…600 s
P04
Min. on time delay
0…600 s
P05
Dead band between cooling and heating off points
0.5…6 K
P06
RV on in heating or cooling mode
Heating/Cooling
P07
Fan run on after heating output turns off
0…300 s
P08
Fan run on after cooling output turns off
0…300 s
P09
FCU flush pipe time
120…600 s
P11
Water temperature heating mode changeover
22…32 °C
P12
Water temperature cooling mode changeover
10…21 °C
P13
Fan auto speed high range
H: 80…100 %
P14
Fan auto speed medium range
M: 30…75 %
P15
Fan auto speed low range
L: 1…15 %
P17
2- or 3-position control selection
2-pos / 3-pos
P18
P-band in heating mode / switching differential
0.5…10 K
P19
P-band in cooling mode / switching differential
0.5…10 K
P20
Integration time
0…60.0 min in
0.5 min steps
P21
3-position valve actuator running time
50…300 s
P23
Ventilation in dead zone
Off, H/C, C only
Response on startup
User operation
Sensor calibration
Commissioning
Setup parameters
