Siemens Desigo RXC32.1 User manual

CA2N3845en_06
2013-06-18
Building Technologies
3845
Desigo™ RXC
Room controller
RXC32.1 / RXC32.5
for VAV systems,
with LONMARK-compatible bus communication
The RXC32 controller is used for VAV room temperature control in individual
rooms.
•Control of the supply or extract air with volume control dampers, with or
without reheaters
•Downloadable application software
•LONMARK-compatible bus communications
•For use in the Desigo building automation and control system
•Control of damper actuators with AC 24 V, 3-position signal
•Control of electric or LPHW reheaters with AC 24 V or AC 24 V 3-position
signals
•Built-in air flow sensor
•AC 24 V operating voltage

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Application
The RXC32 controller is optimised for the control of variable air volume (VAV) systems.
It is designed for control of the supply or extract air with volume control dampers. The
controller may also be used for the control of electric or LPHW reheaters.
The controller application is determined by downloadable application software, also
referred to simply as the “application”. The various applications and the associated
functions are described in detail in the applications library (V1: CA2A3810,
V2: CA110300).
The controllers are delivered pre-loaded with a particular application or with basic
application 00032. The basic application, which contains only I/O module functions, is
overwritten with the definitive application in the commissioning phase. The RXT10
commissioning and service tool is used for this purpose (see “Commissioning”).
In conjunction with a building automation and control system, the RXC32 controller can
also be used as a universal I/O module, e.g. to register digital signals or to control
various equipment (ON/OFF or pulse control with AC 24 V). In this case the controller is
loaded with basic application 00032. The inputs can then be read and the outputs
overridden via the building automation and control system.
Functions
The controller functions are determined by the selected application and its parameters.
For a detailed description of functions, refer to the Desigo RXC applications library (V1:
CA2A3810, V2: CA110300).
Certain input and output parameters can be set for various functions making it possible
to cover a wide range of VAV systems. (For parameter settings for the various
applications, refer to the Desigo RXC applications library (V1: CA2A3810,
V2: CA110300).
Input
Function
D1
−Occupancy sensor (volt-free contact)
−Window switch (volt-free contact)
D2
X1 −LG-Ni 1000 temperature sensor (passive)
−
Air quality sensor (DC 0…10 V)
Output
Function
Y1 and Y2
−
3-position damper actuators (AC 24 V)
Y3
−Radiator with thermic valve (AC 24 V, PDM)
−Electric reheater (AC 24 V, on/off)
Y4
Y3 and Y4
−
LPHW reheater with motorised valve (AC 24 V, 3-position)
When Desigo RXC is integrated into a building automation and control system
additional functions become available such as time scheduling, central control of
setpoints, etc. (refer to the Desigo INSIGHT documentation for further information).
Use as an I/O module
Inputs and outputs
Integration into the
building automation
and control system

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Types
Type SSN Description
RXC32.1
RXC32.5
S55373-C116
Room controller for VAV systems
RXZ30.1 Accessory: Terminal covers
Ordering
When ordering please specify the quantity, product name and type code.
The controllers will be delivered with basic application 00032.
The RXZ30.1 terminal covers are supplied in packs of 1 pair and must be ordered
separately).
Example:
30 Room controllers for VAV systems RXC32.5/00032
30 Pairs of terminal covers RXZ30.1
Compatibility
For operation of the RXC32 room controller, a room unit from the QAX… series may be
used in conjunction with conventional momentary contact switches for lighting and blind
control. Alternatively, the flexible room units, QAX50.1 or QAX51.1 may be used.
See the RX hardware overview (CA2N3804) for a summary of the available field
devices.
Mechanical design
The RXC32 controller consists of a housing base, a housing cover and the printed
circuit board with connection terminals. The controller also has a tool socket, a service
LED and a service pin.
Connection
for volume
measurement (+)
Housing cover
Connection
for volume flow
measurement (-)
90130
Cable restraints
Plug-in
connection terminals
for LONWORKS® bus
Housing base
Service LED
Service pin
Tool socket

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Terminal covers (RXZ30.1) are available as an option to protect the connection
terminals from physical contact and contamination. The terminal covers also provide
strain relief for the cables. The service LED remains visible when the terminal covers
are in place, and the service pin can be operated with a pointed implement. When
fitting the terminal covers ensure that they lock into place.
80049
Removing the terminal cover
Bar code, Code 128
(Identification)
Identification number
Protection standard
Temperature range
(0 … 50 °C)
Test date, series
(Z, A, B, C…)
Serial No.
Factory-loaded
application
Definitive
application
Location
Options for use of the labeling fields “Appl.” and “Loc.”:
−Hand-written entry of the location and the actual application… or
−Printed adhesive label (printed from the RXT10 commissioning and service tool)
All connection terminals are detachable plug-in terminals. They are arranged so that,
under normal circumstances, all incoming and outgoing cables can be connected
without crossing.
The conductors to the connection terminals can be
secured with cable ties to the housing base.
80170
Terminal covers
Label
Note
Connection terminals
Cable strain relief

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The sensor uses an integrated NTC thermistor to measure the cooling effect of the air
flow. The effect of the air temperature is compensated by the sensor. The controller
processor calculates the air flow by means of the sensor signal.
The RXC32 controller communicates with other devices via the following interfaces:
•LONWORKS® bus (terminals CLA and CLB) for communication with:
−the PXR system controller or the NIDES.RX interface (to Desigo)
−other Desigo RXC devices
−LONMARK-compatible 3rd party devices (e.g. presence detector)
•PPS2 (terminals CP– and CP+):
−Interface to the QAX… room units. (In addition to PPS2, the LONWORKS® bus is
also looped to the tool socket on the room unit.)
•Tool socket (RJ45) on the controller or room unit, for:
−RXT10 commissioning and service tool (LONWORKS® bus)
−RXT20.1 service terminal (PPS2)
The diagram below shows the wiring of the LONWORKS® bus and PPS2 interface when
a QAX… room unit is connected. It also shows the options for connecting the RXT10
commissioning and service tool and the RXT20.1 service terminal.
The yellow service LED shows the current operational status of the controller by means
of different flashing patterns (see the RXT10 user manual, CM110669).
The service pin is used to identify the controller in the commissioning phase. When the
pin is pressed the controller’s identification number is transmitted to the RXT10
commissioning and service tool.
Flow sensor
Communication
LONWORKS®-Bus
and PPS2
Service LED
Service pin

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Disposal
The devices are classified as waste electronic equipment in terms of the European
Directive 2002/96/EC (WEEE) and should not be disposed of as unsorted municipal
waste.
The relevant national legal rules are to be adhered to.
Regarding disposal, use the systems setup for collecting electronic waste.
Observe all local and applicable laws.
Engineering notes
The Desigo RXC installation guide, document CA110334, contains the relevant
engineering information for the LONWORKS® bus (topology, bus repeaters, bus
termination, etc.) and for the selection and dimensions of connecting cables for the
supply voltage and field devices.
See “Connection diagrams” for information on connecting field devices.
The controller operates with an AC 24 V supply voltage (SELV / PELV). The supply
cable must be protected with at least 10 A.
The controlled devices (valves and damper actuators) are supplied directly from the
controller. The maximum load on the outputs must not be exceeded (see “Technical
data”).
This device has no circuit breakers for supply lines to external consumers (field power
supply)!
Line insulation must always be sufficient for the available rated voltage.
When forwarding supply voltage (for 24 V low voltage as well) to external consumers,
the wiring cross sections must at any rate be adapted to the preswitched overcurrent
protection device. Please comply under all circumstances with local regulations.
The power consumption of the connected devices must be taken into account when
sizing the transformer.
•The simultaneous load on outputs Y3… Y6 must not exceed 24 VA.
•The maximum load on each output must not exceed 12 VA.
Equipment
Y1, Y2
1 3-position motorised actuator GDB…1E
2 VA
Y3 (Cooling)
2 thermic valve actuators, type STP72E
6 W
Y4 (Heating)
2 thermic valve actuators, type STP72E
6 W
Simultaneous load:
2 motorised actuators (both ON continuously)
4 VA
2 thermic valve actuators *
6 W (12 W) **
10 W (16 W)
* The heating and cooling sequences are never operative simultaneously. Therefore,
only the actuators for one of the two sequences need to be included when
calculating the total load.
** When cold, thermic valve actuators have a consumption of approximately 6 W. A
maximum of two thermic actuators may be connected to any one Y... output.
AC 24 V supply
Caution
AC 24 V triac outputs
Example

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Mounting
The controller can be mounted in any orientation as follows:
90131
90131
Rail mounting
The housing base is designed for snap-
mounting on DIN rails, type EN50022-
35x7.5 (can be released with a
screwdriver)
Surface mounting
There are four drill holes for screw
mounting (see “Dimensions” for drilling
diagram). The housing base is fitted
with raised supports.
Screws: Max. diameter 3.5 mm
When mounting note the following:
•Ensure adequate air circulation to dissipate heat generated during operation.
•Easy access is required for service personnel.
•Local installation regulations must be observed.
The mounting instructions and a drilling template are printed on the controller
packaging.
•Avoid bends and constrictions when connecting the tubing
•Connect the “+” connection to the higher pressure side and the “–“ connection to the
lower pressure side.
•The recommended tube length is in the range 700 mm … 2 000 mm
•When using an air filter, install it on the high pressure side (“+”), with the air flowing
through the filter in the correct direction.
•Use an air filter to prevent the accumulation of dirt particle deposits on the sensor
element, especially when the extract air is contaminated (see technical data).
Commissioning
The RXC32 controller is commissioned with the RXT10 commissioning and service
tool. This is connected to the LONWORKS® bus via a tool socket (on the controller or
room unit).
The commissioning procedure for the entire Desigo RXC range is described in detail in
the RXT10 user manual, document CM110669.
The labeling fields “Appl.” and “Loc.” on the controller are used to indicate the
application actually loaded and the location of the controller, either in writing or by use
of printed adhesive labels (see “Label” under “Mechanical design”).
Connection, flow sensor
Labeling

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All applications (including basic application 00032) allow direct interrogation of the
inputs and control of the outputs using the RXT10 commissioning and service tool. This
makes it possible to test the installation and to operate connected plant provisionally
before the complete Desigo RXC system is commissioned.
•The LONWORKS® bus plug (terminals 23 and 24) can be removed and reconnected
at any time, even while the controller is in operation. Only the original bus plug may
be used.
•Overloading outputs Y1 … Y4 may cause the thermal fuse to trip and disable the
controller. After solving the problem, briefly disconnect and reconnect the power
supply. The controller will resume normal operation after a delay of approximately 10
minutes.
•Outputs Y1 … Y4 are not protected against accidental connection to AC 24 V.
This can damage the triacs.
•For accurate measurement of the air volume, make sure that the tubes are
connected correctly.
Technical data
Power supply Operating voltage SELV / PELV AC 24 V ± 20 %
Rated voltage
AC 24 V
Frequency
50/60 Hz
Power consumption
Without field devices
With field devices
6 VA
Max. 33 VA
Caution
Internal fuse
Thermal, automatic reset
Supply cable protection (external fuse)
Transformer with secondary limitation
of
max. 10 A or
External secondary power fuse with
max. T 10 A non-renewable fuse or
max. C 13 A circuit breaker
is required in all cases
Inputs Signal inputs for volt-free contacts
Quantity
Contact voltage
Contact current
Contact transfer resistance
Contact insulation resistance
Not suitable for pulse control
2 (D1, D2)
DC 33 V
DC 8 mA
Max. 100 Ω
Min. 50 kΩ
Measured value input for temp. measurement
Quantity
Suitable temperature sensors
Measuring range
Sensor current
Resolution
Accuracy
1 (X1) 1)
LG-Ni 1000
–40 ... 110 °C
2.5 mA
≤0.2 K
At 25 °C ±0.2 K
1) X1 selected by option button in RXT10 tool LG-Ni 1000 / 0 ...10 V
Function test
Notes
STOP
Note!

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Outputs
Caution
Supply outputs For field supply
Output voltage
Fuse
AC 24 V (transit power)
No internal fusing
Fusing on the supply line required
under all circumstances
Triac outputs AC 24 V
Quantity
Output voltage
Permissible load current
Power limitation
Total nominal load
(load on all triacs simultaneously)
4 (Y1 ... Y4)
AC 24 V on/off, PDM or 3-position
(selected by switch)
Max. 0.5 A
1.85A PTC, resetting
(common for all triacs)
Max. 24 VA
Flow sensor
Tube connections (nipple diameters)
Measuring range
Overload range
Volume measurement
Accuracy with dynamic calibration
Accuracy with static calibration
∅5.2 mm
0…300 Pa
0…100 k Pa
CEN TC247 Accuracy class 2
CEN TC247 Accuracy class 1
Air filter Example: air filter ALG 3 ½ SPF Can be ordered from Schupp AG
(www.sf-filter.ch), order number AL700/1.
Interfaces Interface with room unit
Number of room units connectable
Interface type for room unit
for RXT10
PPS2 baud rate
LON baud rate
Max. 1
PPS2
LON
4.8 kBit/s
78 kBit/s
LONWORKS®-Bus
Interface type
Transceiver
Baud rate
Bus topology and bus termination
LON (LONMARK-compatible),
electrically isolated
on RXC32.1: FTT-10A
on RXC32.5: FT 5000
78 Kbps
See Installation guide, CA110334
Cable connections Plug-in terminal blocks
Solid conductors
Stranded conductors without
connector sleeves
Stranded conductors with connector sleeves
(DIN 46228/1)
Rising cage terminals
1 x 0.2 ... 2.5mm2
or 2 x 0.2 ... 1.0 mm2
1 x 0.2 ... 2.5mm2
or 2 x 0.2 ... 1.5 mm2
1 x 0.25 ... 2.5mm2
or 2 x 0.25 ... 1.0 mm
2
Max. tightening torque
0.6 Nm
Single cable lengths
Signal inputs D1, D2
Measured value input X1
Triac outputs AC 24 V, Y 1 … Y4
Interface to room unit
Cable type
LONWORKS® bus
Cable type
Tool connecting cable
See Installation guide, CA110334
Max. 100 m with diameters ≥0.6 mm
Max. 100 m with diameters ≥0.6 mm
Max. 100m where A ≥1.5 mm2
Max. 115 m where A= 0.75 mm2
(including tool connecting cable)
4-core, twisted pair, unscreened
See Installation guide, CA110334
See Installation guide, CA110334
Max. 3 m length

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Housing protection standard Protection standard to EN 60529 IP30 with terminal cover fitted and
wall mounted without DIN rail
All other mounting arrangements: IP20
Protection class
Insulation protection class
III
Ambient conditions Operation
Temperature
Humidity
Class 3K5 to IEC 60,721-3-3
0 ... 50 °C
< 85 % rh
Transport
Temperature
Humidity
Class 2K3 to IEC 60,721-3-2
– 25 ... 65 °C
< 95 % rh
Standards and directives
Product safety
Automatic electronic controls for household
and similar use
EN 60730
-1
Electromagnetic compatibility
Immunity (ndustrial & residential)
EN 60730-1
Emissions (residential)
EN 60730-1
compliance
Meets requirements of EMC directive
2004/108/EC
Meets requirements of RoHS directive
2011/65/EU
UL compliance
UL916
C-Tick conformity (EMC)
AS/NZS 61000-6-3
Environmental compatibility The product environmental declaration
CA2E3840 contains data on RoHS com-
pliance, materials composition, packaging,
environmental benefit, disposal
ISO 14001 (Environment)
ISO 9001 (Quality)
Dimensions See dimension diagrams
Width in DIN modular spacing units 8.5
Weight
Excluding packaging
0.28 kg