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5.7.20 Operation with up to four return air sensors - only UA 131 E LS
Only controller type UA 131 E LS
Using the parameter Temperat. R4.3orTemperat. R4.4 (menu 6-3 Return air sensors), the operation of up to
four return air sensors (in one temperature zone) can be enabled, see table.
Number of return air sensors
Temperature zones UA 401 E CC UA 400 E CC / UA 410 E AC
Single-zone operation 2
Zone 1: R4.1 / R4.3
2 up to max. 4
Zone 1: R4.1 / R4.3 / R4.2 / R4.4
Two-zone operation
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2
Zone 1: R4.1 / R4.3
Zone 2: R4.2 / R4.4
For details, see Terminal assignment of the analogue inputs for temperature sensors.
Configuration
The parameters Temperat. R4.3andTemperat. R4.4mustbesetto"ON"forthisoperatingmode.Usingthe
parameter Wichtung R4.3, the temperature regulation between the sensors R4.1 and R4.3 and between R4.2
and R4.4 with the parameter Wichtung R4.4 can be set. With a weighting value of 0%, regulation is carried out
completely according to the original sensor (R4.1 or R4.2), and with a weighting value of 100% completely
according to the respective second sensor (R4.3 or R4.4). Intermediate values result in regulation to the
weighted average of both sensors.
5.8 Defrosting
5.8.1 Typesofdefrosting–anoverview
The following types of defrost are described in the following chapters:
Defrost in general
Discharge gas defrosting (hot gas defrosting)
Master/slavemode–defrostsynchronisationviaCANbus
Master/slavemode–defrostsynchronisationviawiring
Defrost sequenz (DS) via CAN bus
ATTENTION
In this operating mode the sensors R5.1 and R5.2 for determining the superheat are not required! As
the emergency features are thus omitted (failure of the suction pressure measurement via R5.1 or
R5.2), suitable measures must be taken to take into account the absence of the evaporator inlet
sensors R5.1 and R5.2. A suitable measure is the standalone operation using activated local pressure
transmitter.
ATTENTION
Fire hazard! On grounds of fire prevention, during the planning of the installation a device for shutting
downthedefrostheatingintheeventofexcessivetemperature(e.g.”KLIXON”)mustbeprovided.