Siemens RWD68U Owner's manual

RWD68U
Technical Instructions
Document No. 155-738
January 14, 2005
Universal Controller
Description The Universal Controller is intended for heating, air conditioning, ventilation and
refrigeration in comfort control applications. RWD68U main loop control applications
are designed for temperature, static pressure, humidity, air pressure, fluid pressure,
refrigeration, air quality and air fluid velocity control. The controller contains pre-
programmed applications.
Auxiliary control functions include:
• Day/night setpoints
• Remote setpoint control
• Limiter control
• Cascade control
• Maximum priority
• Setpoint compensation
• Summer/winter operation
Control parameters are adjusted for maximum comfort control via three buttons on the
face of the device, or with a laptop computer and Siemens Building Technologies
program software.
NOTE: For complete supporting technical documentation, including training
presentations, see www.us.sbt.siemens.com/hvp/components.
Features • Stand-alone electronic temperature controller with P or P+I response
• 24 Vac operating voltage
• Control application selectable via Application Number
• Active input scale can be selectable
• Limit and direction of the output scale can be freely assigned
• Two universal inputs for Siemens 1000 ohm nickel (Ni 1000), 1000 ohm platinum
(Pt 1000) temperature sensors and 0 Vdc to 10 Vdc signals
• Unit can be set as °F, °C, % or no specified unit
• One modulating 0 to 10 Vdc signal output, direct or reverse action
• One two-position output, direct or reverse action
• One digital input for day/night changeover
• Entering or changing of all data via operating buttons on the controller, is possible
without additional tools
• Computer connection for downloading pre-programmed applications via the
software tool
Product Number RWD68U
Siemens Building Technologies, Inc.

Technical Instructions RWD68U Universal Controller
Document Number 155-738
January 14, 2005
Accessories ARG62.21 Protective enclosure for wall mounting.
SEH62.1U Program Clock
SHM62.2U 24/120 Vac Transformer
125-3481 RWD Controller Programming Tool (CD)
RWDTKU Tool Kit
Warning/Caution Notations
CAUTION:
Equipment damage may occur if you do not follow a
procedure as specified.
Specifications
Power Supply
Operating voltage 24 Vac + 20%
Frequency 50/60 Hz
Power consumption 3.0 VA
LCD Actual and nominal values Four digits
Setpoint adjustment range -58°F to 302°F (-50°C to 150°C)
Display Resolution
(does not relate to controller
accuracy)
Siemens Ni 1000 ohm 1°F (0.5°C)
Pt 1000 ohm 1°F (0.5°C)
Active sensor Depends on setting range
Environmental Conditions Storage and transport
Temperature -13°F to 158°F (-25°C to 70°C)
Humidity <95% rh
Operation
Temperature 32°F to 122°F (0°C to 50°C)
Humidity <95% rh
Regulatory Approvals Conforms to requirements
UL UL listed to 916 Energy
Management Equipment
Terminals Screw terminals, min./max. conductors Minimum: 24 AWG (1)
Maximum: 16 AWG (2), or 14 AWG (1)
Weight RWD68U Controller 10.72 oz (304 grams)
With packaging 12.64 oz (358 grams)
Analog Inputs X1, X2
Siemens Ni 1000 ohm @ 32°F
(0°C)
Controller measuring range -58°F to 302°F (50°C to 150°C)
Maximum cable length for 14 AWG 984 ft (300 m)
Pt 1000 ohm at 32°F (0°C) Controller measuring range -4°F to 356°F (-20°C to 180°C)
Maximum cable length for 14 AWG 984 ft (300 m)
Analog voltages
(For measured variable in °F.
°C, % or without unit)
Range 0 to 10 Vdc corresponding to
adjustable range from –100 to
8000 (°F, °C, % or no unit)
Maximum cable length for 14 AWG 984 ft (300 m)
Remote setpoint X2 Range 0 to 1000 ohm corresponding to
adjustable range from –100 to
8000 (°C, °F, % or no unit)
Maximum cable length for 14 AWG 984 ft (300 m)
Digital input D1 Polling voltage for control commands (D…M) 15 Vdc
Current consumption <15 mA
Analog outputs Y1, Y2 Range 0 to 10 Vdc
Maximum current +1 mA
Digital output (Q1) Relay contacts (potential-free)
Voltage: 24 Vac
Maximum rating: 24 Vac to 240 Vac
6A RES/5 FLA/30 LRA/1/2 HP
30 Vdc, 4A
Page 2 Siemens Building Technologies, Inc.

RWD68U Universal Controller Technical Instructions
Document Number 155-738
January 14, 2005
Function Summary • Controller
Stand-alone controller with one direct or reverse acting 0 to 10 Vdc output and
one two-position (ON/OFF) output with dependent and independent adjustment
on each sequence for direct acting or reverse acting. Adjustable parameters,
including proportional band and integral action time.
• Auxiliary selectable function
• Universal input X2 for one of the following auxiliary functions:
− P+I limiter function (Absolute and Relative)
− Remote setpoint
− Cascade control
− Setpoint compensation
− Winter/summer operation
− Maximum priority
• Digital input D1 for setpoint changeover day/night
Equipment
Combinations
The following Siemens devices can be connected to RWD68U Universal Controllers.
Other combinations with units from third-party manufacturers are possible, if the
input and output specifications match the RWD68U.
Table 1.
Description Document Number
Sensor with Siemens Ni 1000 temperature sensing element
QAA25U Room temperature sensor with setpoint adjuster
155-330
Differential Pressure Sensor 155-719
GIB Series 310 lb-in Non Spring Return Actuators
GBB Series 177 lb-in Non Spring Return Actuators
155-176P25
155-177P25
GEB Series 132 in-lb Non Spring Return Actuators 155-318P25
GCA Series 142 in-lb Spring Return Actuators 155-173P25
155-174P25
155-175P25
GMA Series 62 in-lb Spring Return Actuators 155-315P25
SKD Valve Actuator with proportional input
SKD Valve Actuator with floating input
155-180P25
155-181P25
SKB/SKC Valve Actuator with proportional input
SKB/SKC Valve Actuator with floating input
155-163P25
155-171P25
SQX Valve Actuator with proportional input
SQX Valve Actuator with floating input
155-182P25
155-186P25
SQS Actuator with proportional input
SQS Actuator with floating input
155-190P25
155-191P25
SSC Actuator with proportional input
SSC Actuator with floating input
155-313P25
155-314P25
SSB Actuator with proportional input
SSB Actuator with floating input
155-192P25
155-195P25
SFA/SFP two-position valve actuators 155-321P25
Electric Rack and Pinion two-position actuator 155-541P25
1/2 to 2-inch two-way globe valves 155-184P25
1/2 to 2-inch three-way globe valves 155-185P25
2-12 to 6-inch two-way flange valves 155-159P25
2-1/2 to 6-inch three-way flange valves 155-160P25
MT Series 1/2 to 1-1/2-inch two-way globe valves 155-196P25
MT Series 1/2 to 1-1/2-inch three-way globe valves 155-197P25
MZ Series 1/2 to 1-inch two-way globe valves 155-198P25
MZ Series 1/2 to 1-inch three-way globe valves 155-199P25
1/2 to 1-inch zone valves 155-320P25
Siemens Building Technologies, Inc. Page 3

Technical Instructions RWD68U Universal Controller
Document Number 155-738
January 14, 2005
Software Tool An optional, user-friendly, Windows® 95 (or later) based software tool for controller
application selection and parameter adjustment is available. It provides you with a
printout of the controller settings. This tool allows controller programming prior to
installation.
Functions
Controller Type
The RWD68U is a stand-alone universal controller, which performs both primary and
auxiliary control functions. The respective mode is defined by entering the
corresponding configuration and setting parameters via the push buttons on the
controller or the software tool.
Main Functions The RWD68U controller can be programmed as follows:
• One sequence: Q1 Reverse or direct acting
• Two sequences: Y1 and Q1 Reverse and direct acting or
Y1 and Q1 Reverse and reverse acting (independent
and dependent control loop) or
Y2 and Q1 Direct and direct acting (independent and
dependent control loop)
NOTE: Direct Acting – As air temperature increases, the control output increases.
Reverse Acting – As air temperature increases, the control output
decreases.
TH0599R3
= TEMPERATURE SENSOR
= AIR DAMPER ACTUATOR
= HEATING COIL
= COOLING COIL
= HEATING OR COOLING COIL (TWO-PIPE)
= FAN OR PUMP
= TIME CLOCK
= REMOTE SET POINT UNIT
= OUTSIDE AIR SENSOR
+
+
-
-
Figure 1. Frequently Used Symbols in Application Drawings.
TH0746R1
OFF
ON
SD SD
22
SD
Setpoint
Temp.
Figure 2. Reverse Acting Sequence
(Application 10 to 19).
TH0747R1
OFF
ON
SD SD
22
SD
Setpoint
Temp.
Figure 3. Direct Acting Sequence
(Application 80 to 89).
TH0748R1
Y1
XP
OFF Temp.
Setpoint
Heating Cooling
Q1
SD
SD SD
22
ON
Min V
Ouptut
Voltagee
Max V
Figure 4. Reverse and Direct Acting
Sequences
(Application 40 to 49).
TH0749R1
Y1
Min V
Temp.
Setpoint
Heating Cooling
Ouptut
Voltagee
OFF
ON
Q1
SD1
SD1 SD1
22
Max V
Figure 5. Direct Acting Sequences
(Application 50 to 59).
Page 4 Siemens Building Technologies, Inc.

RWD68U Universal Controller Technical Instructions
Document Number 155-738
January 14, 2005
Dependent Control Loops
TH0751R1
Y1
Max V
Heating
Temp.
Setpoint
Output
Voltage
Q1
OFF
ON
Min V
Figure 6. Two Direct Acting
Sequences
(Application No.: 20 to 29).
TH0750R1
Y1 Max V
Cooling
Temp.
Setpoint
Output
Voltage
Q1
OFF
ON
Min V
Figure 7. Two Reverse Acting
Sequences
(Application 60 to 69).
Independent Control Loops
TH0752R1
Y1
Min V
Temp.
Setpoint
XP
Heating Heating
Ouptut
Voltagee
OFF
ON
Q1
SD
SD SD
22
Max V
Figure 8. One Reverse Acting, One
Direct Acting Sequence
(Application 30 to 39).
TH0753R1
Y1
Min V Temp.
Setpoint
Cooling Cooling
Ouptut
Voltage
OFF
ON
Q1
SD
SD SD
22
Max V
Figure 9. Two Direct Acting
Sequences
(Application 70 to 79).
Universal Input X1 The primary input for a Siemens Ni 1000 temperature sensor, a Pt 1000 temperature
sensor, or a 0 to 10 Vdc active input.
Universal Input X2 The secondary input for a Siemens Ni 1000 temperature sensor, a Pt 1000
temperature sensor, an active/passive remote setpoint transmitter, or a 0 to 10 Vdc
active input.
Digital Input D1 Selects the day/night changeover. Changeover occurs via potential-free contacts
between D1 and M. Typically, a time clock controls D1 input.
Analog Output Y1 Output Y1 can be configured for either reverse or direct acting. The modulating
voltage output (Y1) controls the devices requiring a 0 to 10 Vdc signal.
Digital Output Q1 Output Q1 can be configured for either reverse or direct acting control.
Example
TH0754R1
X1
Y1Q1
Temp.
Y
Q1
X1 Room temperature
Q1 Heating, reverse action
Y1 Cooling, reverse action
Figure 10. Constant Volume with Temperature Control,
Reverse Acting/Reverse Acting.
TH0754R1
X1
Y1Q1
Temp.
Y
Q1
X1 Room temperature
Q1 Heating, direct action
Y1 Cooling, direct action
Figure 11. Constant Volume with Temperature Control, Direct Acting/Direct Acting.
Siemens Building Technologies, Inc. Page 5

Technical Instructions RWD68U Universal Controller
Document Number 155-738
January 14, 2005
Auxiliary Functions One of the following auxiliary functions can be selected:
• P+I limiter (Absolute, #x2 and Relative, #x3)
• Remote setpoint, #x1
• Cascade control, #x5
• Setpoint compensation, #x4
• Winter/summer operation, Digital #x6, Analog #x7
• Maximum priority, #x8
• Main loop 0 to 10V input, #x9
Day and night operation mode is also available.
P+I Limiter Function
NOTE: In the following
illustrations, heating
and cooling outputs
are Direct Acting.
Outputs can be
reversed.
TH0755R1
X1
Q1Y1
Temp.
Y
X2
Q1
Figure 12. P+I Limiter Function.
The limiter function with P+I control
enables absolute (or relative) maximum
or minimum limitation of the supply air
temperature (X2).
When the value drops below or exceeds
the limiter setpoint, the limiter function
controls and takes priority over the main
setpoint.
Remote Setpoint
NOTE: You cannot select
the remote setpoint
auxiliary function in
Night mode.
TH0756R1
X1
Y1Q1
Temp.
YX2
Q1
Figure 13. Remote Setpoint.
A remote setpoint transmitter (QAA25U),
connected to X2 and configured
accordingly, enables setpoint
adjustment.
Active measurement from 0 to 10 Vdc
corresponding adjustable range from
–100 to 8000 units.
Passive measurement from 0 to 1000 Ω
corresponding adjustable range from
–100 to 8000 units.
Cascade Control
TH0757R1
X1
Y1
Temp.
Y
X2
Figure 14. X2 Supply Air Temperature
Sensor.
You can select the P+I/P+I room/supply
air temperature cascade control. In this
case, the virtual P+I room temperature
controller determines the setpoint within
the limiter setpoints for the P+I supply air
temperature controller.
Maximum Priority
NOTE: You cannot select
the maximum priority
auxiliary function in
Night mode.
TH0758R1
X2
Y1
Temp.
YX1
Q1
Q1
Figure 15. Maximum Priority,
Cooling.
If the value (0 to 10V) of the input X2 is
greater than the calculated output of the
cooling sequence, the output will use the
X2 input value as output value. This is
active even when the controller is
working with the heating sequence.
Page 6 Siemens Building Technologies, Inc.

RWD68U Universal Controller Technical Instructions
Document Number 155-738
January 14, 2005
Setpoint Compensation
TH0759R1
X2
Y1Q1
Temp.
YX1
Figure 16. Setpoint Compensation.
The temperature setpoint X1 is shifted
by the temperature as measured at
sensor X2.
Configuration of the RWD68U defines
the influence on setpoint X1.
The example shows the room air
temperature setpoint as shifted by the
outside temperature.
Winter/Summer Operation
TH0760R1
X1
Y1
Temp.
YX2
T
Summer
Setpoint Winter Setpoint
Figure 17. Winter/Summer Operation.
A digital switch or analog input between
terminals X2 and M can be used to
implement winter/summer changeover.
When adjusting setpoints, the heating
setpoint must be less than the cooling
setpoint.
Digital changeover
Summer operation is selected when the
contact is closed. Reverse acting output
(Y1 only) is set to direct action (cooling).
Analog changeover
Summer operation is selected when the
X2 input exceeds the Setpoint. Reverse
acting output (Y1 only) is set to direct
action (cooling).
NOTE: The reverse acting output
changeover occurs in Y1 only
for application numbers 36, 37,
56 and 57; and in Q1 only for
16, 17, 46 and 47.
Day/Night Setpoint
TH0761R1
X1
Y1
Temp.
Y
D1 Q1
Q1
Figure 18. Day/Night Setpoint.
A contact between terminals D1 and M
can be used to implement setpoint
changeover for day/night operation.
When the contact is open, the setpoints
for day operation are selected.
When the contact is closed, the setpoints
for night operation are selected.
During the night mode, the following
auxiliary functions are disabled: remote
setpoint, absolute/relative limiter,
setpoint compensation, and maximum
priority.
Siemens Building Technologies, Inc. Page 7

Technical Instructions RWD68U Universal Controller
Document Number 155-738
January 14, 2005
Mechanical Design
Protective Housing
ARG62.21
• This UL-approved plastic housing protects the controller when mounted outside a
control panel, such as on ducts, walls and in mechanical rooms. This housing
also prevents inadvertent contact with voltage supplying parts such as the
connecting terminals.
• The RWD68U clips into the housing.
• The cable entries are located at the top and the bottom of the ARG62.21
housing.
• The front has an opening for the LCD display and the programming buttons.
Terminals Plug-in screw terminals
Operating and Display
Elements The RWD68U is operated by the buttons on the controller front. Additional tools are
not necessary. The controller can also be programmed via the software tool, which
plugs into the nine-pin port.
TH0762R1
LCD Display
Software Tool
Nine Pin Port
Program and Display
Function Buttons
Figure 19. RWD68U Universal Controller.
LCD The LCD shows the following information for normal operation:
• Current operating values (maximum four digits)
• Current setpoints (day/night)
• Application number
• Control sequencing diagram
• Auxiliary input value
• Selected auxiliary function
Operating Buttons The controller has three operating buttons for the following functions:
The SELECT ●button is used to enter or save the value adjustment.
The operating buttons are used for viewing and adjusting parameters.
Configuration To configure the controller, follow the instructions supplied with the controller.
Page 8 Siemens Building Technologies, Inc.

RWD68U Universal Controller Technical Instructions
Document Number 155-738
January 14, 2005
Installation Notes The RWD68U Controller can be mounted as follows:
NOTE: Observe all local installation regulations and building codes.
A On a DIN rail at least 4.7 inches (120 mm) long
B Wall-mounted with two screws
C Front-mounted using standard hardware:
• One DIN rail 5.9 inches (150 mm) long
• Two hexagonal blocks 1.97 inches (50 mm)
• Washers and screws
D In the ARG62.21 protective housing
AB C D
TH0550R1
Figure 20. Mounting Options.
Electrical Installation Notes
CAUTION:
• Standard cables can be used for the controller. However, when
mounting in an environment greatly exposed to Electrical Magnetic
Interface (EMI), use only shielded cables.
• The RWD68U is designed for 24 Vac operating voltage.
• Use safety insulating transformers with double insulation; they
must be designed for 100% duty.
• When using several transformers in one system, the connection
terminals G0 (ground) must be galvanically connected.
• Supplying voltages above 24 Vac to low voltage connections may
damage or destroy the controller or any other connected devices.
• Connections to voltages exceeding 24 Vac endanger personal
safety.
• The ARG62.21 Protective Housing does not provide grounding
between conduit connections. Use grounding bushings and jumper
wires or equivalent.
Commissioning Notes A commissioning booklet is included with the RWD68U Controller.
Observe the following:
• The controller must be configured for application-specific operation using the
standard application number.
• Application-specific fine tuning can be performed if required (see the
commissioning booklet).
• Power supply to the controller and the connected devices must be guaranteed.
• Values and settings entered remain available even on power failure.
Siemens Building Technologies, Inc. Page 9

Technical Instructions RWD68U Universal Controller
Document Number 155-738
January 14, 2005
Wiring Diagrams
TH0763R1
G0 Q11
D1 M X1 M X2 M G
Q14
Y1 M
Tool
Q12
Figure 21. RWD68U Wiring Diagram.
D1 Digital input
G, G0 24 Vac supply
M Ground (G0) for signal inputs and
universal inputs and analog
outputs
Q11 Common for digital contact
Q12 NC digital contact
Q14 NO digital contact
X1 Signal input (main input: Siemens
Ni 1000, Pt 1000 and
0 to10 Vdc)
X2 Signal input (aux. Input:
Siemens Ni1000, Pt 1000,
0 to10 Vdc and 0 to 1000 Ωor
0 to 10 Vdc remote setpoint)
Y1 Analog output
Tool Communication port for PC
(9-pin plug)
TH0764R1
Y1
G
Y1
S1
D1
GO
Y..
BM BM
X1 X2MM
X2X1
M
M
GO
G
24 V SN
24 V SP
N1
TOOL
PC
Q12 Q14
Q11
Q1
E1
GG
E1 Electrical load
N1 RWD68U Controller
PC Personal computer
Q1 Potential-free relay contacts for two-position control
S1 Time clock or switch
SN System neutral
SP System potential
X1 Main input (Termination G appears when X1 is an active sensor)
X2 Auxiliary input or remote setpoint (Termination G appears when X2 is an
active sensor)
Y1 Valve actuator/Damper actuator
Figure 22. Connection Diagram.
CAUTION:
If you use a DESKTOP computer, the TOOL signal ground is
galvanically connected to G0 inside the controller. If the signal line of
the computer is grounded to Earth, the G0 line after TOOL connection
will be grounded as well.
Page 10 Siemens Building Technologies, Inc.