Room pressurization with air volume flow tracking and temperature control, heating coil, cooling coil or ceiling heating/chilled ceiling or radiator with two room segments

 

  • For pressurized rooms with VAV actuators and optional fume hoods
  • Supply and exhaust air volume control for fast, precise VAV damper actuators on 0...10 V outputs
  • Airflow coordination and tracking of supply air/exhaust air ratio for positive/negative air flow control
  • Ventilation control to remove and dilute air contaminants for rooms with defined air change rates
  • Temperature control by adapting volume air flow (air change rate), cooling coil, or ceiling heating/chilled ceiling or radiator
  • Monitoring of VAV air volume flows and min. room air volume flow (Air Change Rate)
  • Configurable control functions by means of unused inputs and outputs

Plant diagram

DXR2…
BE
BS
DW
DP
RU
R
YS
YC
YHC
YH
YE

Room automation station
Exhaust air temperature sensor
Supply air temperature sensor
Door switch/Window contact
Presence detector
Room operator unit with temperature sensor
Room
VAV supply air control including actuator YSM and pressure sensor YSP
Chilled water cooling coil
Cooling/heating coil
Hot water heating coil or electric heating coil
VAV exhaust air control including actuator YSM and pressure sensor YSP

 

Function diagrams / sequence diagrams

Heating and cooling valve, air volume flow

V
Y
YH
YC
TR
SpH
SpC

Air volume flow (Setpoint)
Output signal
Heating coil valve
Cooling coil valve
Room temperature
Heating setpoint
Setpoint cooling

Minimum air volume flow

VavSuAirFlMaxH
VavSuAirFlMinH
VavSuAirFlMaxC
VavSuAirFlMinC
VavSuAflMinVnt

Maximum volume flow Heating
Minimum volume flow Heating
Maximum volume flow Cooling
Minimum volume flow Cooling
Minimum volume flow Ventilation

Function description

Basic functions

  • PID control for supply and exhaust air VAV, room pressurization, temperature and air quality
  • The following priority prevails if functions conflict: 1. Room pressurization, 2. Air change rate, 3. Temperature control.
  • Alarms for room pressurization and ventilation
  • Room pressurization with door contact to freeze room pressure control loop
  • The room operator unit measures temperature, humidity, and air quality (CO2).
  • The application allows customers to adjust the room temperature setpoints and rapid ventilation via the room operator unit
  • Display of room air quality on room operator unit
  • The operating modes are Comfort, Pre-Comfort, Economy and Protection
  • The air flow for heating and cooling is operated in sequence to the valves. Parallel operation can be configured
  • Supports VAV damper actuators for supply and exhaust air 0…10 V.
  • Regular automatic pressure sensor calibration (DXA.S04P…)

Options

  • Exhaust VAV actuator 0…10 V
  • PID control LTHW radiator heating
  • Heating and cooling coils with 3-position valves controlled via triac outputs
  • Control for supply air humidification
  • Downdraft compensation
  • Outside temperature (for downdraft compensation) distributed over BACnet
  • Optimal energy efficiency by including the option for room/supply air cascade control, presence detector or window contact
  • Optional system alarms displayed on the management station notify building operators of possible faults
  • Optional trends can be activated for room sensors

Auxiliary functions

  • Rapid ventilation
  • Air volume flow tracking for positive and negative room air pressure
  • Damper position transmission for pressure-optimized fan control (Air-Opticontrol)
  • Green Leaf function (energy saving indication)
  • Multisegment use of DXR2 automation stations with VAV application
  • Control via central commands (e.g. scheduler for room operating mode)
  • Central optimum start control provides best room comfort at the start of occupancy
  • Central operation or reset of setpoints, timed valve kick function or outside temperature dependent heating limit
  • Central override functions for valves
  • Emergency function with maximum air change rate and tracking of supply air/exhaust air volume ration
  • Summer/winter compensation of room temperature setpoints
  • Configurable, generic universal control functions for free I/Os

Variants

  • PWM constant (including spring return) or PWM thermal control can be selected for valves
  • Room operator unit and sensor variants:
    KNX PL-Link wall-mount sensor
    KNX PL-Link flush-mount room operator unit
    KNX PL-Link flush-mount sensors
    Analog exhaust air temperature sensor
  • KNX PL-Link sensor or binary sensor detects presence

 

Siemens devices

Description

Device type

Data sheet

Type

Qty.

DXR2…

Compact room automation station, BACnet/IP, 24 V,
DIN housing, 3 DI, 2 BI, 4 UI, 4 DO triacs, 4 AO 0…10 V

A6V10959860

DXR2.E17CX-103A

1

RU

KNX PL-Link room operator unit with sensors for temperature, humidity, CO2, segmented backlit display, touchkeys

N1602

QMX3.P34

1

YS, YE

VAV damper actuator, AC 24 V, DC 0...10 V, 6 Nm, 2 s

N4608

GAP191.1E

2

YSP, YEP

Airflow Pressure Sensor, AC 24 V, SCOM, 0..250 Pa with or without installation box

A6V101063803

DXA.S04P1 or DXA.S04P1-B

2

 

Optional 1)

Description

Device type

Data sheet

Type

Qty.

BP, BS, BE

Cable temperature sensor PVC 2 m, LG-Ni1000

N1831

QAP22

4

DW

Door/window contact, white

2)

S 290/11

23)

DP

KNX PL-Link presence detector with brightness sensor

2)

UP 258D12

1 - 4

YC

2-port, 3-port valve or 3-port valve with bypass, PN16

N4847

V...P47...

1

 

Motorized 3-positioning actuator for V...P47..., AC 24 V

N4864

SSP81...

1

YH

2-port, 3-port valve or 3-port valve with bypass, PN16

N4847

V...P47...

1

 

Motorized 3-positioning actuator for V...P47..., AC 24 V

N4864

SSP81...

1

YHC

2-port, 3-port valve or 3-port valve with bypass, PN16

N4847

V...P47...

1

 

Motorized 3-positioning actuator for V...P47..., AC 24 V

N4864

SSP81...

1

YSP,
YEP

Differential pressure sensor, AC 24 V, DC 0...10 V, 0...300 PA

N1925

QBM3460-3

4

1) Can be combined as per available on-board I/Os on controller.
2) Additional documents available at www.siemens.com/gamma-td.
3) Type of operation (NC or NO). Multiple devices of the same type can be connected.

Connection diagram

Application configuration

Group

Equipment

Values/range

Template settings

On-board output

Variable air volume
Supply air

Y1, Y2; 3-position
Y10; Y30; 0...10 V
Setpoint for air volume flow; Y10, Y30; 0...10 V

Y10; 0...10 V
Y30; 0...10V

Variable air volume

Exhaust air

Y3, Y4; 3-position
Y20; Y40; 0...10 V
Setpoint for air volume flow; Y20, Y40 0...10 V

Y20; 0...10 V
Y40; 0...10V

On-board input

Exhaust air differential pressure

X1; X3; 0…10V, 4...20mA; SCOM

P1; P3; SCOM

Supply air differential pressure

X2; X4; 0…10 V, 4...20mA; SCOM

P2; P4; SCOM

KNX PL-Link devices

Room operator unit 1

QMX3.P02, QMX3.P34, QMX3.P36, QMX3.P37, QMX3.P74

QMX3.P34

Optional configuration

Group

Equipment

Values/range

Template settings

On-board output

Cooling coil valve

Water; Y1/Y2; Y3/Y4; 3-position
Water; Y1; Y3; pulse width modulation thermal
Water; Y1; Y3; pulse width modulation spring return
Water; Y10; Y20; Y30; Y40; 0...10 V

 

Heating/cooling valve

4-pipe, 6-way; Y10; Y20; Y30, Y40; 0..10 V
4-pipe; Y1, Y2, Y3, Y4; pulse width modulation thermal
4-pipe; Y1, Y2, Y3, Y4; pulse width modulation spring return
4-pipe; Y10; Y20; Y30, Y40; 0...10 V

 

Heating coil valve

Water; Y1/Y2; Y3/Y4; 3-position
Water; Y1; Y3; pulse width modulation thermal
Water; Y1; Y3; pulse width modulation spring return
Water; Y10; Y20; Y30; Y40; 0...10 V
Electric 1-stage; Y1; Y3; NC (normally closed)
Electric 2-stage; Y1, Y2 or Y3, Y4; NC
Electric modulating; Y1; Y3; pulse width modulation constant period
Electric modulating; Y10; Y20; Y30, Y40; 0..10 V

 

Enable electric heating coil

Y1; Y3 NC

 

Ceiling heating/chilled ceiling valve 1...2

Cooling; Y1/Y2; Y3/Y4; 3-position
Cooling; Y1; Y3; pulse width modulation thermal
Cooing; Y1; Y3; Pulse width modulation spring return
Cooling; Y10; Y20; Y30; Y40; 0...10 V
Heating/cooling 2-pipe; Y1, Y2; 3-position
Heating/cooling 2-pipe; Y1; Y3; Pulse width modulation thermal
Heating/cooling 2-pipe; Y1; Y3; Pulse width modulation spring
Heating/cooling 2-pipe; Y10; Y20; Y30; Y40; 0...10 V
Heating/cooling 4-pipe 6-way; Y10; Y20; Y30; Y40; 0...10 V
Water; Y1/Y2; Y3/Y4; 3-position
Heating; Y1; Y3; Pulse width modulation thermal
Heating; Y1; Y3; Pulse width modulation spring return
Heating; Y10; Y20; Y30; Y40; 0...10 V
Chilled ceiling active: Y10; Y20; Y30; Y40; 0...10 V
Chilled ceiling active; Y1/Y2; Y3/Y4; 3-position
Ceiling heating/chilled ceiling passive; Y1; Y3; Pulse width modulation thermal
Ceiling heating/chilled ceiling passive; Y1; Y3; Pulse width modulation spring return
Ceiling heating/chilled ceiling passive 2-pipe; Y10; Y20; Y30; Y40; 0...10 V
Ceiling heating/chilled ceiling passive 4-pipe 6-way; Y10; Y20; Y30; Y40; 0...10 V

 

Radiator valve 1...2

Water; Y1/Y2; Y3/Y4; 3-position
1) Water; Y1; Y3; pulse width modulation thermal
2) Water; Y2; Y4; pulse width modulation thermal
1) Water; Y1; Y3; pulse width modulation spring return
2) Water; Y2; Y4; pulse width modulation spring return
Water; Y10; Y20; Y30; Y40; 0...10 V
1) Electric 1-stage; Y1; Y3; NC
2) Electric 1-stage; Y2; Y4; NC
Electric modulating; Y1; Y3; pulse width modulation constant period
Electric modulating; Y10; Y20; Y30, Y40; 0...10V

 

Enable output radiator electric 1...2

1) Y1; Y3; NC
2) Y2; Y4; NC

 

Dehumidifier position

Y10; Y20; Y30; Y40; 0...10 V

 

Enable humidification

Y1; Y2; Y3; Y4; NC

 

Binary output 1..4

Y1; Y2; Y3; Y4; NC

 

Analog output 1..2

Y10; Y20; Y30; Y40; 0...10 V

 

On-board input

Room temperature

X1; X3; LG-Ni1000, 0...10V; NTC100k, NTC 10k, T1 (PTC); Pt1000 (EU, NA); 4...20mA

 

Supply air temperature

X2; X4; LG-Ni1000, 0...10 V; NTC100k, NTC 10k, T1 (PTC); Pt1000 (EU, NA); 4...20mA

X2; X4; LG-Ni1000

Exhaust air temperature

X1; X2; X3; X4; LG-Ni1000, 0...10 V; NTC100k, NTC 10k, T1 (PTC); Pt1000 (EU, NA); 4...20mA

X1; X3; LG-Ni1000

VAV differential pressure supply air

P1; P3; SCOM
X1 ; X3 ; 0...10V
X1 ; X3 ; 0...20mA

 

Supply air VAV air velocity

X1; X3; 0...10 V

 

Supply air VAV air volume flow

X1; X3; 0...10 V

 

VAV differential pressure exhaust air

P2; P4; SCOM
X2; X4; 0...10 V
X2; X4; 0...20mA

 

Exhaust air VAV air velocity

X2; X4; 0...10 V

 

Supply air VAV air volume flow

X2; X4; 0...10 V

 

Room pressure

X1; X2; X3; X4; 0...10 V
X1; X2 X3; X4; 0...20mA

 

Demand control ventilation setpoint input

X1; X2; X3; X4; 0...10 V

 

Room air quality

X1; X2; X3; X4; 0...10 V

 

Relative room air humidity for room

X1; X2; X3; X4; 0...10 V
X1; X2 X3; X4; 0...20mA

 

Relative room air humidity for duct

X1; X2; X3; X4; 0...10 V
X1; X2 X3; X4; 0...20mA

 

Primary air temperature for air after-treatment

X1; X2; X3; X4: LG-Ni1000, 0...10 V; NTC100k, NTC 10k, T1 (PTC); Pt1000 (EU, NA); 4...20mA

 

Brightness

X1; X2; X3; X4; 0...10 V

 

Door/window contact

D1; D2; D3; NO (normally open)
X1; X2; X3; X4; NO

D1, D2

Presence detector 1..2

D1; D2; D3; NC

 

Emergency off

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Heating coil overtemperature detector

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Radiator overtemperature detector

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Condensation monitor for chilled ceiling

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Condensation monitor VAV cooling coil

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Humidity detector in duct

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Flow sensor

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Blinds collision detector 1...2

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Binary input 1...7

D1; D2; D3; NO
X1; X2; X3; X4; NO

 

Analog output

P1; P2; P3; P4; SCOM
X1; X2; X3; X4: LG-Ni1000, 0...10 V; NTC100k, NTC 10k, T1 (PTC); Pt1000 (EU, NA); 4...20mA

 

Default values

Group

Parameter

Values/range

Template settings

Temperature setpoints

Cooling setpoint for Comfort

0...50 °C

24 °C

Delta cooling setpoint for Pre-comfort

0...10 K

1 K

Cooling setpoint for Economy

0...50 °C

35 °C

Cooling setpoint for Protection

0...50 °C

40 °C

Heating setpoint for Comfort

0...50 °C

21 °C

Delta heating setpoint for Pre-comfort

0...10 K

1 K

Heating setpoint for Economy

0...50 °C

15 °C

Heating setpoint for Protection

0...50 °C

12 °C

CO2 air quality control

Setpoint room air quality for Comfort

0...2000 ppm

900 ppm

Setpoint room air quality for Pre-comfort

0...2000 ppm

1100 ppm

Setpoint room air quality for Economy

0...2000 ppm

1500 ppm

Setpoint room air quality for

Protection

0...2000 ppm

1500 ppm

Supply air VAV

Supply air VAV max. air volume flow
Cooling

0...10,000 m3/h

100 m3/h

Supply air VAV min. air volume flow
Cooling

0...10,000 m3/h

50 m3/h

Supply air VAV max. air volume flow
Heating

0...10,000 m3/h

100 m3/h

Supply air VAV min. air volume flow
Heating

0...10,000 m3/h

50 m3/h

Supply air VAV max. air volume flow
Ventilation

0...10,000 m3/h

100 m3/h

Supply air VAV min. air volume flow
Ventilation

0...10,000 m3/h

0 m3/h

Room operator unit

Room unit, temperature display

None
Display room temperature

Display room temperature

Room unit, window state display

Yes, No

No

Room unit, air quality display

None

Display room temperature

Display room air quality

Room unit, air quality display

Numeric (in ppm)
Symbolic (with symbols +, ++ and +++)
Text (Poor, OK, Good)

Textual

Room unit, display heating/
cooling state

Yes, No

Yes

Enable operation:
Room temperature setpoint

Yes, No

Yes

Room unit, room temp.
Setpoint display

Absolute temperature setpoint

Relative setpoint shift

Relative setpoint shift

Enable operation: Fan speed
setpoint

Yes, No

Yes

Enable operation: Presence button

Yes, No

No

Enable operation: Temporary
Comfort

Yes, No

No

Enable operation: Room operating mode

Yes, No

No

Enable operation: Green Leaf

Yes, No

Yes

 

Engineering

  • The ABT Site engineering tool is required to engineer DXR2 automation stations.
  • See the Siemens Download Center at www.siemens.com/bt/download for the latest application configuration and workflow tutorials.
  • Options combined as per available on-board - I/Os.

 

Management platform

Example of VAV applications in Desigo CC