Siemens Desigo RXC20.1 User manual

CA2N3834en_09
2013-06-16 Building Technologies
s
3834
Desigo™ RXC
Room controllers RXC20.1 / RXC20.5
RXC21.1 / RXC21.5
RXC22.1 / RXC22.5
For fan-coil systems, chilled ceilings and radiators
with LONMARK® compatible bus communications
The RXC20, RXC21 and RXC22 room controllers are used for temperature control
in individual rooms.
For 2-pipe or 4-pipe fan-coil systems, with or without change-over
For chilled ceilings and radiators
Control of AC 24 V PDM 1) thermic valve actuators, 3-position AC 24 V valve
and damper actuators, or electric heating coils
Volt-free relay contacts for fan control and electric heating coils
PI or PID control (depending on application)
Downloadable application software
LONMARK® compatible bus communications
For use in the Desigo building automation and control system
AC 230 V operating voltage
1) PDM = pulse/duration modulated

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Use
The RXC20, RXC21 and RXC22 room controllers are optimized for control of fan-coil
systems, chilled ceilings and radiators in individual rooms.
The following versions are available for fan-coil systems:
RXC20: 1-speed automatic fan control
RXC21: 1- to 3-speed automatic fan control
RXC22: 1- to 3-speed automatic fan control
with integrated relay for electric re-heating
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 RXC applications library. (V1: CA2A3810,
V2: CA110300).
The room controllers are delivered with the basic application 00020 (RXC20),00021
(RXC21) and 00022 (RXC22), respectively. 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 system, the RXC20, RXC21 and RXC22 room
controllers can also be used as universal I/O modules, e.g. to register binary signals or
to control various equipment (ON/OFF or pulse control with AC 24 V or volt-free relay
contacts).
In this case, the room controllers are loaded with basic application 00020, 00021 and
00022, respectively. The inputs can then be read and the outputs overridden via the
building automation system.
Functions
The room controller functions are determined by the selected application and its pa-
rameters and by the input/output configuration.
For a detailed description of functions, refer to the Desigo RXC applications library (V1:
CA2A3810, V2:CA110300).
When Desigo RXC is integrated into a building automation system additional functions
become available such as time scheduling, central control of setpoints, etc. (refer to the
Desigo INSIGHT documentation for further information).
The RXC20, RXC21 and RXC22 room controllers differ only in the number of outputs
they provide:
Type SSN AC 24 V triac outputs Relay outputs
RXC20.1
RXC20.5
S55373-C111
For two thermic valve actuators
or one 3-position actuator
For 1-speed fan control
RXC21.1
RXC21.5
S55373-C112
For four thermic valve actuators
or two 3-position actuators
For 3-speed fan control
RXC22.1
RXC22.5
S55373-C113
For two thermic valve actuators
or one 3-position actuator
For 3-speed fan control
Internal relay for electric
heating coil
RXZ20.1 Accessories: Terminal covers
Use as an I/O module
Types

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Ordering
When ordering please specify the quantity, product name, type code and application.
The controllers are delivered with the basic application 00020, 00021 or 00022, respec-
tively.
The RXZ20.1 terminal covers are supplied in packs of 1 pair and must be ordered sep-
arately.
Example:
30 RXC20.5 room controllers RXC20.5/00020
30 Pairs of terminal covers RXZ20.1
Compatibility
The QAX… room units and the Siemens field devices can be used with the RXC20,
RXC21 and RXC22 room controllers.
For details, refer to the RX hardware overview, CA2N3804.
Design
The RXC20, RXC21 and RXC22 room controllers consist 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.
Plug-in Connection terminals
Housing cover
Plug-in Connection terminals
70198
Cable restraints
Plug-in
connection terminals
for LONWORKS® bus
Housing base
Service LED
Service pin
Tool socket
Terminal covers (RXZ20.1) are available as an option, to protect the connection termi-
nals from physical contact and dirt. The service LED remains visible when the terminal
covers are in place, and the service pin can be operated with a pointed implement. The
cable is connected to the room controller by breaking out the perforated cable entry
guide.
70200
Removing the terminal cover
Terminal cover

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Neuron ID
Bar code, Code 39
(ID number)
Protection standard
Temperature range
(0 … 50 °C)
Serial No.
Test date, series
(Z, A, B, C…)
Observe notes
in this document
Factory-loaded
application
Definitive
application
Location
Options for use of the labeling fields “Appl.” and “Loc.”:
Hand-written entry of the location and the loaded application ... or
Printed adhesive label (printed from the RXT10 commissioning and service tool)
All connection terminals are detachable plug-in terminals.
To avoid incorrect wiring, terminals which can be connected to AC 230 V (supply and
relay outputs) are physically separate from the other terminals.
Cable restraints must be used for the wires to termi-
nals 19 … 28 (AC 230 V). The conductors must be
secured with cable ties (see diagram).
3834J01
Ensure that the power is off before inserting or removing plug-in terminals
connected to a mains voltage.
The RXC20, RXC21 and RXC22 room controllers communicate with other devices via
the following interfaces:
L
ONWORKS® bus (terminals CLA and CLB) for communication with:
PXX-Lxx, PXR system controller or NIDES.RX interface (to Desigo)
Other Desigo RXC devices
L
ONMARK®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 room controller or room unit, for:
RXT10 commissioning and service tool (LONWORKS® bus)
RXT20.1 service terminal (PPS2)
Label
(example RXC22.5)
Note
Connection terminals
STOP Note!
Warning!
Communication

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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 room controller by
means of different flashing patterns (see the RXT10 user manual, CM110669).
The service pin is used to identify the room controller in the commissioning phase.
When the pin is pressed the room controller’s identification number is transmitted to the
RXT10 commissioning and service tool.
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 RX installation guide, document CA110334, contains the relevant engineer-
ing 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.
The room controllers have an AC 230 V mains supply voltage. The controlled devices
(valves and damper actuators) are supplied directly from the room controller.
This means that a separate AC 24 V supply is not necessary for the RXC20, RXC21
and RXC22 room controllers and the associated field devices.
LONWORKS® bus
and PPS2
Service LED
Service pin

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The dimensions and fuse protection for the supply cables depend on the total load
and on local regulations. The cables must be secured with cable restraints.
If serial wiring is applied on the terminal block 19/21, the connection will be inter-
rupted if the block is removed from the controller (the jumpers 19-19 and 21-21 are
on the PCB, not in the block, see terminal diagrams on pages 10 … 12).
The volt-free relay outputs allow switching of loads up to AC 250 V, 5 A (4 A). The heat-
ing coil relay in the RXC22 switches resistive loads up to 1.8 kW.
The cable dimensions depend on the connected load and the local installation regula-
tions. The circuits must be externally fused (10 A) as there are no internal fuses.
The cables must be secured with cable restraints.
Parallel operation of the fans is not permitted.
The simultaneous load on outputs Y1 … Y4 must not exceed 9.5 VA.
Example: Y1 (heating) 2 thermic valve actuators, type STP72E 6 W
Y2 (cooling) 2 thermic valve actuators, type STP72E 6 W
Y3, Y4 (outside air) 3-position damper actuator 3.5 VA 3.5 VA
The maximum load is 9.5 VA for the heating sequence and 9.5 VA for the
cooling sequence. This is acceptable because the two sequences never
operate at the same time.
When using small loads (< 2VA), the voltage tolerance may be > + 20%
(see technical data, Triac outputs below)
Mounting instructions
The room controllers can be mounted in any orientation using the following fixing options:
70202
70203
Rail mounting
The housing base is designed for snap-
mounting on DIN rails, type EN50022-35 x
7.5 (can be released with a screwdriver).
Surface mounting
There are two drill holes for screw-mounting (see “Dimensions” for drill-
ing template). The housing base is fitted with raised supports.
Screws: Max. diameter 3.5 mm, min. length 38 mm
STOP Note!
Tightening torque for fixing screws max. 1.5 Nm
AC 230 V supply cables
AC 230 V volt-free
relay outputs
STOP Note!
AC 24 V triac outputs

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When mounting note the following:
The controller should not be freely accessible after mounting.
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.
Commissioning notes
The RXC20, RXC21 and RXC22 room controllers are commissioned with the RXT10
commissioning and service tool. The RXT10 is plugged into the tool socket on the
room controller or room unit for connection to the LONWORKS® bus.
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.” 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”).
All applications (including basic applications 00020, 00021 and 00022) allow interroga-
tion of the inputs and control of the outputs using the RXT10 commissioning and ser-
vice tool. This enables the fan-coil manufacturer to test the installed units before deliv-
ery.
The LONWORKS® bus plug (terminals 17 and 18) can be removed and reconnected at
any time, even while the controller is in operation. Only the original bus plug may be
used.
In the event of a long-term short circuit (approx. 4 minutes) or overload,
the thermal fuse in the transformer may trip.
Subsequently, the device must be exchanged.
There is no protection against accidental connection on the AC 24 V side.
Mains AC 230 V for the supply and for the relays must be disconnected before
plugging and unplugging the terminal blocks (danger of electric shock!)
If serial wiring is applied on the terminal block 19/21, the connection will be
interrupted if the block is removed from the controller (the jumpers 19-19 and
21-21 are on the PCB, not in the block, see terminal diagrams on pages 10 … 12).
Labeling
Function test
Note
STOP Note!

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Technical data
Power supply Operating voltage
A
C 230 V ± 10 %
Rated voltage
A
C 230 V
Frequency 50/60 Hz
Power consumption with
output field devices connected max. 12 VA
Internal fuse Thermal, non-resetting
Operating data Control algorithm PI or PID
Inputs
Signal inputs D1, D2 Quantity 2
(for volt-free contacts) Contact voltage DC 16 V
Contact current DC 8 mA
Contact transfer resistance max. 100 
Contact insulation resistance min. 50 k
Not suitable for pulse control
Measured value input B1 Compatible temperature sensors LG-Ni 1000
Quantity 1
Measuring range 0 ... 50 °C
Sensor current 2.3 mA
Resolution 0.2 K
Measuring error at 25 °C sensor temp. (exclud-
ing cable)
max. 0.2 K
Outputs
A
C 24 V triac outputs, Y1 ... Y4 Quantity 2 (RXC20, RXC22)
4 (RXC21)
Output voltage
A
C 24 V ON/OFF, PDM or 3-position: +/–20%
(May exceed +20% with loads under 2VA)
Output current max. 0.5 A
Total nominal load
(at both outputs simultaneously)
max. 9.5 VA (e.g. 2 thermic valves, type
STE72 per heating and cooling sequence +
1 damper actuator 3.5 VA)
Relay outputs Q14, Q24, Q34 Quantity 1 (RXC20)
3 (RXC21, RXC22)
Relay type single pole
Contact rating with AC voltage
Switching voltage max. AC 250 V, min. AC 19 V
Nominal current, resistive/inductive max. AC 5 A/4 A (cos = 0.6)
Making current 200 ms half-time max. 20 A
Switching current at AC 29 V min. AC 10 mA
Contact rating with DC voltage
Switching voltage max. DC 250 V, min. DC 5 V
Switching current at DC 5 V min. DC 100 mA
Switching capacity max. 20 W
Inductive load L/R max. 7 ms
Q44 Relay type single pole
Contact rating with AC voltage
Max. admissible load (purely resistive) max. 1.8 kW
External fuse (essential) max. 10 A
STOP ..Note! Q44 is only permitted for mains voltage,
not for security extra low voltage
Interfaces
Interface to room unit Number of room units connectable max. 1
Interface type for room unit
for RXT10
PPS2
LONWORKS® bus
PPS2 baud rate 4.8 kbps
LONWORKS® baud rate 78 kbps
LONWORKS® bus Interface type LONMARK® compatible,
electrically isolated
Transceiver on RXC2X.1: FTT-10A, on RXC2X.5: FT 5000
Baud rate 78 kbps
Bus topology, bus termination see installation guide, CA110334

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Cable connections Plug-in terminal blocks
Solid conductors
Stranded conductors without connect-
or 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 mm2
Max. tightening torque 0.6 Nm
Single cable lengths see also installation guide, CA110334
Signal inputs D1, D2 max. 100 m with diameters 0.6 mm
Measured value input B1 max. 100 m
AC 24 V triac outputs, Y1 ... Y4 max. 100m where A 1.5 mm2
Relay outputs Q14, Q24, Q34, Q44 depends on load and local regulations
Interface to room unit max. 115 m where A= 0.75 mm2
(including tool connecting cable)
Cable type 4-core, twisted pair, unscreened
LONWORKS® bus max. 500 m
Cable type see installation guide, CA110334
Tool connecting cable max. 3 m
Housing protection standard Protection standard to EN 60529 IP30 with terminal cover fitted and
wall mounted without DIN rail
IP20 for all other mounting arrangements
Protection class Suitable for use in systems with protection class I or II
Ambient conditions Operation class 3K5 as per IEC 60721-3-3
Temperature 0 ... 50 °C
Humidity < 85 % r.h.
Transport class 2K3 as per IEC 60721-3-2
Temperature – 25 ... 65 °C
Humidity < 95 % r.h.
Standards and directives - Product standards EN 60730
marking
- EMC
Immunity (industrial & residential)
Emission (residential)
2004/108/EC
EN 60730-1
EN 60730-1
- Low Voltage Directive
Electrical safety
2006/95/EC
EN 60730-1
- RoHS
Techn. RoHS proof
2011/65/EU
EN 50581
Electronic individual zone control equipment EN 15500
UL compliance UL916
C-Tick conformity (EMC)
A
S/NZS 61000-6-3
eu.bac Meets the requirements for eu.bac certification
See product list at: http://www.eubaccert.org/ licences-by-criteria.asp
Type License
A
pplication Control
accuracy [K]
RXC20.5 20737 Fancoil 2 pipes heating / coooling 0.2 / 0.1
Heating systems (radiator) 0.3
Electric convectors 0.2
Chilled ceiling systems 0.3
RXC21.5 20705 Fancoil 2 pipes heating / coooling 0.2 / 0.1
Fancoil 2 pipes / 2 wires heating / coooling 0.2 / 0.1
Fancoil 4 pipes heating / coooling 0.2 / 0.1
Chilled ceiling systems 0.3
Environmental compatibility The product environmental declaration
CA2E3834 contains data on RoHS compliance,
materials composition, packaging, environmental
benefit, disposal
ISO 14001 (Environment)
ISO 9001 (Quality)
Dimensions See dimension diagrams
Weight Excluding packaging 0.59 kg

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Connection terminals
3804A02
123456789 13141516 1718
M D1 GND D2 Y1 G Y2 G CP– CP+ CLA CLB B1
CLA CLB
1234
QAX...
T
M
19 19 21 25 26
N L Q13 Q14 N
AC 230 V 5(4) A
21
L
LonWorks®
Bus
Measured value input
B1 1 Measured value input with LG-Ni 1000 sensor
M 2 Measured value input ground
Signal inputs
D1 3 Signal input
GND 4 Signal ground
D2 5 Signal input
Triac outputs
Y1 6 AC 24 V, 0.5 A switching output
G 7 AC 24 V actuator supply
Y2 8 AC 24 V, 0.5 A switching output
G 9 AC 24 V actuator supply
Room unit
CP– 13 PPS2 ground
CP+ 14 PPS2 data
CLA 15 Data A
CLB 16 Data B
LONWORKS® bus (plug-in)
CLA 17 Data A
CLB 18 Data B
Power supply
N 19 Neutral conductor
L 21 Phase line AC 230 V +/- 10 %
Relay output
Q13 25 Feed for Q14
Q14 26 N/O contact AC max. 250 V, 5 (4) A
Observe the technical data for the relay output: Max. AC 250 V, 5 (4) A
Local installation regulations must be observed.
Standard RJ45 tool socket for LONWORKS® devices.
1
3206Z01
2345678
1 LONWORKS®, Data A (CLA)
2 LONWORKS®, Data B (CLB)
3 Unoccupied
4 Unoccupied
5 Unoccupied
6 unoccupied
7 PPS2 (CP+)
8 PPS2 (CP–)
RXC20
STOP Note!
Tool socket