MDT Technologies SCN-RT2UP.01, Manual

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Technical Manual Temperature Controller
MDT technologies GmbH • 51766 Engelskirchen • Papiermühle 1
Tel.: +49-2263-
880 • Fax: +49
-2263-4588
• knx@mdt.de • www.mdt.de
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The changeover of the operating modes via 1 Byte occurs by only one object, with the size of 1 Byte,
the DPT_HVAC Mode 20.102 of KNX-specification. Additional, there are 2 objects for the visualization
a aila le, the B te o je t DPT_HVAC “tatus a d the B te o je t DPT_RHCC “tatus . Fo the
changeover of the operating modes, a Hex-
alue is se t to the o je t ode sele tio .
The object
evaluates the received value and switches the belonging operating mode on and the active operating
mode off. If all operating modes are switched off (Hex-value=0), the operating mode standby will be
switched on.
The Hex-values for the operating modes are shown at the chart:
Operating mode (HVAC Mode) Hex-Value
Comfort 0x01
Standby 0x02
Night 0x03
Frost/Heat protection 0x04
Table 18: Hex-Values for operating modes
The following example shall clarify how the controller handles received Hex-values and switches
operating modes on or off. The chart is to read from the top to the down.
Example:
The priority was set as
Frost/Comfort/Night/Standby.
received Hex-value Handling adjusted operating
mode
0x01 Comfort=1 Comfort
0x03 Comfort=0
Night=1
Night
0x02 Night=0
Standby=1
Standby
0x04 Frost-/Heat protection=1
Standby=0
Frost-/Heat protection
Table 19: Example operating mode changeover via 1 Byte
The DPT HVAC Status communication object, DPT_HVAC Status (without number) of KNX-
specification, sends the hex value for the adjusted operating mode. When more than one testify is
valid, the hex values are added and the communication object sends the added value. The hex values
can be read from visualization afterwards.
The following chart shows the hex values for the single messages:
Bit DPT HVAC Status Hex-Value
0 Comfort 1=Comfort 0x01
1 Standby 1=Standby 0x02
2 Night 1=Night 0x04
3 Frost-/Heat protection 1= Frost-/Heat protection 0x08
4
5 Heating/Cooling 0=Cooling/1=Heating 0x20
6
7 Frost alarm 1=Frost alarm 0x80
Table 20: Hex-Values DPT HVAC Status
If you heat at the comfort mode, the communication object will send the value 20 (for heating) +1
(for the comfort mode) =21.