domat UI90 Series User manual

domat UI90x 9/2019 Subject to technical changes. 1
UI90x
Communicative room unit with CO2sensor
Summary
The room unit with CO2sensor contains temperature sensor, NDIR CO2sensor for
carbon dioxide concentration measurement, optional humidity sensor, and
control knob for setpoint control and other settings. The binary output is
controlled either on a remote basis, or as thermostat, hygrostat or CO2controller.
The units communicate over Modbus RTU / RS485 and they can be used as open
system components with majority of building control system and controllers.
Compared to the old series UI09x, these types dispose of knob and display blue
backlight function and more accurate sensors.
All versions of the room units now contain relative humidity measurement. UI092
and UI094 versions have been replaced.
Beware of unit terminals connection. It differs from its predecessor.
Application
▪Air handling units and air condition in rooms with variable load –
schools, cinemas, lecture halls etc.
▪monitoring and recording of temperature, and CO2concentration
indoors
Function
The units acquire temperature, CO2concentration, and optionally relative humidity in
the room, temperature correction (controlled by the knob) and required operation
status which is set by short push of the knob or in the menu. In the configurable menu
following values can be set and displayed:
–temperature, actual temperature correction
–humidity (actual value only at room units containing the humidity sensor)
–time (only display at room units with RTC)
–basic setpoint - day
–basic setpoint - night
–outside temperature for heating enable

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–DHW temperature
–heating curve type (1...4)
–operation mode (Residential with Day, Night, Time schedule, Off, or Hotel /
Office with Comfort, Standby, Party, Off)
–fan stage (Auto, Off, St.1, St. 2, St. 3)
–A/C mode (Auto, Heating, Cooling, Off, Fan only)
–weekly scheduler: 7 days, up to 6 events per day
–another 5 variables (air quality, fan speed etc.) –each has a profile where max.
and min. values, step, number of decimals, and symbol set are defined.
It is also possible to set / reset any of the LCD symbols on the display over Modbus.
The turn / push knob has three basic functions:
•instant edit (turning the knob) –settings of one predefined analogue value,
usually room temperature correction
•quick edit (short push) –change of predefined state, e.g. Presence (Comfort /
Standby / Off), Air condition (Auto / Heating / Cooling / Fan only / Off) etc.
•long push –jump to menu where values are listed by turning the knob, short
push selects the value to be edited, and the value is changed by turning the
knob followed by short push for confirmation.
After definable inactivity time, the display goes back to its basic state with rolling
display of selected values (e.g. actual temperature and CO2).
Backlight
function
Types UI0xxBL dispose of knob and display blue backlight function. It is possible to set
brightness 0-100 % separately for knob and display. If user make some action with
knob, display and knob shine for defined time. All of the functions could be set from
Modbus master.
The unit Modbus address and functionality is defined over the RS485 interface with
service software ModComTool which is free for download at http://domat-
int.com/en/downloads/software To interface the room unit to the computer use the
USB/485 converter M080, RS232/RS485 converter R012, or any suitable RS485
converter.
____________________________________________________________________
Technical data
Power supply
24 V AC +/- 20%, 1 W
Temperature measuring range
-20 ÷ 70 °C (accuracy ±1 ˚C)
Humidity
digital sensor 10 ÷ 90 %rH accuracy ±3%
CO2measuring range
0 ... 5000 ppm (secondary output 0-100%)
CO2measuring method
NDIR (Non-dispersive Infra Red)
CO2measuring accuracy
± 50ppm, ± 3% of measured value (defined conditions
for at least 3 calibration ACDL completed over the
past 3 weeks)
Reaction time of CO2sensor (90 %)
90 seconds heating time (warm-up), 2 minutes, ECDL
calibration (automatic calibration in dimming light
mode), correction of measuring CO2
Protection degree
IP20

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Inputs(specific types only, see table below)
2x potential-free contact (dry contact) against G0, 24
V AC, 5 mA
Outputs (specific types only, see table below)
2x solid state relay, zero switching, for AC load 24 V
AC, max. 0.4 A, AC1, general usage, non-inductive
load according to EN 60947-4-1, galvanic isolation 1.5
kV
Setpoint
according to configuration, +/- 10 to +/- 1 K
Communication
RS485 - Modbus RTU, slave
selectable speed 1200 ... 115200 bps, parity and bits
are set in service SW
default 9600/N/8/1
The interface is optically separated 1 kV.
Display
LCD 60 x 60 mm, symbol set see above
Terminals
recommended wire cross-section 0,14 –1,5 mm2
Cover
ABS, RAL9010, other colours
Weight
0,17 kg
Dimensions
90 x 115 x 30 mm, see below
Ambient conditions
According to class 3K3 (+5 to +40 ° C, 5% to 85% non-
condensing relative humidity).
Storage conditions
According to DIN EN 60721-3-1 Climatic class 1K3 (-5
to +45 ° C, 5% to 95% non-condensing relative
humidity).
Standards conformity
EMC ed.3 EN 61000-6-2: 2005, EN 55022 ed.3:
2010 (industrial environment)
Electrical safety EN 60950-1 ed.2: 2006 + A11: 2009 +
A12: 2011 + A1: 2010 + A2: 2014 + Opr.1: 2012
Restriction of hazardous substances EN 50581: 2012
Terminals
1
2
3
4
5
6
7
8
9
As seen when removing the display part.
The wiring goes towards the center of the
unit so that the cable can be brought
through the aperture in the middle of the
bottom part. DI/DO mix is according types,
see table below.
1: DI1 input 1
2: DI2 input 2
3: DO1 output 1, 24 V AC, against G0
4: DO2 output 2, 24 V AC, against G0
5: G0 power, outputs, inputs –common
point
6: G0 power, outputs, inputs –common
point
7: G power
8: K- communication RS485 -
9: K+ communication RS485 +

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Type table
Type
LCD
Backlighting
Knob
CO2
DI
DO
t
rH
UI900
✓
-
-
✓
✓
UI901
✓
✓
✓
2
2
✓
✓
UI901BL
✓
✓
✓
✓
2
2
✓
✓
UI903
✓
✓
2
2
✓
✓
UI903BL
✓
✓
✓
2
2
✓
✓
UI905
✓
✓
✓
-
-
✓
✓
UI905BL
✓
✓
✓
✓
-
-
✓
✓
UI907
✓
2
2
✓
✓
DIP switches
Back of the PCB
BUS END: if ON, the bus is terminated (if
last device on the line)
USR: not used, reserved for future
applications
INIT: if ON at power-on, sets the controller
into default state and sets bus address to
1, baud rate to 9600 bps.
Another function of the INIT switch is to
bring EEPROM into default factory
settings. To init, proceed as follows:
- connect the device over RS485 to a PC
with domat.exe config tool
- set INIT to ON
- apply power (use only the connector
without bottom)
- find the controller in the tool (Scan)
- set INIT to OFF
- in the ModComTool tool, open the
controller window
- click the Init button in the tool
- remove and apply power.
Measuring
range
The integrated temperature sensor range is -20 to +70 °C. Read and entered values are
available at the RS485 bus where a controller or SCADA reads them. The supervising
system can also write values to the unit (operation mode, fan stage, etc.), which are
displayed on a large LCD display.
The CO2measuring range is 0...5000 ppm. A range defined by two parameters is then
recalculated to 0...100 %, value, which is displayed on the LCD, e.g. 300...2500 ppm
displays as 100...0 % (of air quality) or 0...100 % (of air pollution). At the bus it is possible
to read the absolute value in ppm, too. The parameters are set through the

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configuration software ModComTool or by direct writing into Modbus registers.
Default values are 0% ... 350 ppm (fresh air), 100 % ... 2500 ppm (maximum pollution).
Autocalibration
Transportation and aging may cause sensor drift. The sensor records the lowest reading
and expects that at least once per 8 days the CO2level reaches the outside air
concentration (400 ppm). The lowest measured value is then assigned the 400 ppm
level. Autocalibration does not work if the room is occupied 24 hours a day, or there
are no periods when the gas level drops to background (e.g. greenhouses). Then, the
autocalibration function can be disabled through the configuration program or by
direct writing into the Modbus register. The autocalibration is set to on by default.
During the first days of operation, until the first autocalibration, the sensor may read
values which differ from the real values by several hundreds ppm, e.g. 200 ppm at
night etc. This error is automatically corrected with the first autocalibration.
Room unit as
controller
The binary output (SSR), if available, may be controlled either from a PLC over the bus,
or configured as one of controllers:
•thermostat
•hygrostat (only at devices with rH sensor)
•controller switching at a predefined CO2level.
Setpoint and hysteresis are set over the bus. This function is not suitable for standard
integrated room control, it is to be used as supplementary only. The setpoints are not
influenced by operation modes (Day, Night, Off).
Installation
Units are intended for operating in a normal and chemically non-aggressive
environment. They do not need any servicing or maintenance. Install them in a vertical
position at places where they can be operated easily and measure correct values of
temperature and humidity, i.e. in the height of about 150 cm, with no direct sunlight
or other heat / cool source (AHU outlets, refridgerator, electrical appliances). The
device consists of two parts: bottom with screw terminal block and cover containing
PCB, display, and the knob. The bottom part is fixed by 2 or 4 screws to any flat surface
or a flush-mounting box Ø 50 mm. At the back of the bottom there is an aperture for
cabling. The bottom should be installed and cabling connected first, and the upper part
inserted after the construction works have been finished to prevent damage to the unit.
Seal the conduits to avoid influencing the sensor by draught. Use insulating pad when
installing the sensor on cold walls. Avoid sensor exposition to sunlight or other heat
sources.

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Opening the
cover
When removing the display part, proceed as follows:
-press gently the side parts of the unit and pull the right of the display part by
several milimeters
-pull the left of the display part
-pull the display part and remove it from the bottom.
Do notbend the display part too much, the connector pins could be damaged. The locks
are only at the sides of the display part, not at the top nor bottom.
Communication
The units communicate with a controller (master) over RS485 using Modbus RTU and
thus they can be used in a number of control and SCADA systems. The register
description is available in a separate document Room units UI... –Communication
description. User manual for domat.exe and detailed description of the room unit
functions find in the document Room units configuration –User manual.
Display
Over Modbus, it is possible to set /
reset the complete symbol set except
for the 7 segment digits, „Error“ and
„Setting“ texts, and symbols of °C, °F,
%, and rH. Those are part of the
configurable menu profiles. The
register description is available in a
separate document Room units UI... –
Communication description.
LCD symbol set (see in the picture).

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Dimensions
All dimensions in mm.
RoHS notice
The device contains a non-rechargeable battery which backups the real-time clock and
part of the memory. After the device is not operable, please return it to the
manufacturer or dispose of it in compliance with local regulations.
Safety note
The device is designed for monitoring and control of heating, ventilation, and air
conditioning systems. It must not be used for protection of persons against health risks
or death, as a safety element, or in applications where its failure could lead to physical
or property damage or environmental damage. All risks related to device operation
must be considered together with design, installation, and operation of the entire
control system which the device is part of.

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Changes in
versions
01/2017 —The first datasheet version.
03/2017 —Added picture and description of the installation.
10/2017 —Added Safety note.
09/2019 —UI907 added.