Basic Documentation

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Siemens Bus operator unit RMZ792 Series B CE1P3113en
Building Technologies 4 Supply 07.07.2011
4.2 External supply
We recommend AC 24 V external device supply for fixed installation (e.g. on control
panel door). In this case, the decentralized/central bus supply does not have to carry
the power load required by the bus operator unit, which is thus available to other bus
devices.
• AC 24 V voltage is required to power the bus operator unit externally. It must meet
requirements for SELV/PELV (safety extra low-voltage).
• The transformers used must be safety isolating transformers featuring double
insulation as per EN 60742 or EN 61558-2-6, designed for 100% duty.
• The slider on the rear of the bus operator unit must be set to "EXT".
• AC 24 V is supplied to the bus operator unit via terminals G and G0.
3113A02
KNX
S
EXT
CE+
G0
G
CE
KNX
SP
SN
AC 24 V
4.3 Supply via Synco 700 control unit
In exceptional cases, power may be supplied to the RMZ792 bus operator unit via
a Synco 700 control unit.
• A Synco 700 control unit can only supply power for a bus operator unit if it features
3 or more extension modules.
• The slider on the rear of the bus operator unit must be set to "EXT".
• The bus operator unit is plugged into the service interface of the Synco 700 control
unit using the supplied cable.
S
CE+
G0
G
CE
3113A06
Synco RM...
KNX TP1
45 mA
S1
N1
KNX
EXT
Fault status messages from extension modules may be displayed when the bus
operator unit is plugged in during plant operation. The faults may result in short-term
interruption of plant operation. You must acknowledge and reset the fault status
messages.
Important note