domat UC300 User manual

domat UC300 01/2019 Subject to technical changes. 1
UC300
Communicative floor heating
controller
Summary
UC300 is a communicative floor heating controller with one PWM output for
control of a thermic actuator, or electric floor heater. It can work autonomously,
or in connection to a primary controller (MiniPLC or SoftPLC), building
management system (RcWare Vision or any SCADA), or to UCWEB –the web
interface.
UC300 –basic version with display and knob
UC300/DK –version without knob and display
Applications
▪Systems with water or electrical floor heating –control and measuring of
room temperature
▪monitoring and communication of room temperatures
Function
The controller reads actual room temperature, floor temperature with an external
Pt1000 sensor, setpoint shift by a knob, and set operation status which is set by short
push of the knob. Measured and set values are processed in a PI algorithm, at the
output of which there is a PWM controlled triac. All values are displayed on a large LCD
display.
The floor sensor located in the floor body or at supply water limits the temperature of
the floor and prevents overheating. Maximum floor or water temperature (measured
by the floor sensor) is set in the configuration program or in the controller menu. In
case the sensor is not connected (missing or broken), the limitation is not active and
the controller uses room setpoint and actual value only.
The output works either as PWM controlled by a PI controller, or on/off (thermostat).
The functionality and control parameters, i.e. P and I constants, and hysteresis, can be
set with ModComTool, the configuration software, which is free to download at
http://domat-int.com/en/downloads/software.
The controller contains real time clock with a weekly scheduler (6 events per day). It
changes between three operation modes: Day, Night, and Off. A short push in the Night
mode switches to Party mode –Comfort extension by 2 hours.

2 01/2019 Subject to technical changes. domat UC300
The communication bus is Modbus RTU over RS485, therefore the controllers are easily
to integrate into any SCADA or BMS system. Protocol description is available in a
separate document.
Technical data
Power
24 V st +/- 10%
Consumption
1,5 W + periferie (cca. 5VA)
Measuring range internal sensor
-40 ÷ 125 °C
Measuring range external sensor
-50 ÷ 150 °C
Ambient temperature for controller
0 ÷ 50 °C (display illegible at lower temperatures)
Protection
IP20
Sensor accuracy
+/- 1,5 K (with software correction)
Outputs
1x solid state relay, zero switching, for AC load,
24V AC, max. switching current 0,4A;
recommended thermic actuators are Siemens
STA71, Danfoss TWA (24V types) etc.
Inputs
1x digital input for presence or window contact
1x analogue input for external temperature
sensor Pt1000
Setpoint correction
according to configuration, +/- 10 to +/- 1 K
Communication
2 wire RS485 - Modbus RTU, slave, optically
separated, 1200 ... 115 200 bps
Display
LCD 60 x 60 mm
Terminals
screw terminals for 0,14 –1,5 mm2wires
Cover
ABS, RAL9010, other colours
Weight
0,13 kg
Dimensions
see below
Terminals
1
2
3
4
5
6
7
8
9
Terminals as seen from above in the bottom
part:
1: K- communication RS485 -
2: K+ communication RS485 +
3: DO1 heating valve output
4: DI1 presence /window input
5: G0 power, output –reference point
6: G0 power, output –reference point
7: G power
8: AIN external temperature sensor Pt1000
9: AGND external temperature sensor Pt1000

domat UC300 01/2019 Subject to technical changes. 3
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: sets the controller into default state
and sets bus address to 1, baud rate to 9600.
To init, proceed as follows:
- connect the device over RS485 to a PC with
the ModComTool 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, open the controller
window
- click the Init button in the tool
- remove and apply power.
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, 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.
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.

4 01/2019 Subject to technical changes. domat UC300
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.
User settings
Temperature correction:
Turn the knob clockwise to increase setpoint, turn it counter clockwise to decrease
setpoint. The maximum correction range can be modified over the bus e.g. with the
ModComTool configuration tool.
Operation mode change:
Push the knob shortly (<1 s). Each push changes the operation mode to Party –Day –
Night –Off –Auto.
In the Auto mode, the Day / Night / Off modes change according to time schedule).
The Party mode overrides to Comfort for 120 minutes, then follows the actual time
schedule.
The weekly time schedule switches between Day, Night, and Off modes according to
the event list. There may be up to 6 events per day.
Time schedule settings:
Switch to the time schedule settings mode with a long push (>1 s). The controller
switches to settings mode (clock icon).
Turn the knob to select the weekday (1 to 7). Then short push to confirm the selection.
Turn the knob to select the event (large number 1 to 6). Each event displays the mode
activated by this event.
Short push to confirm the event selection. Turn the knob to select the operation mode
(Day, Night, Off, Event inactive) invoked by this event. If the event is not active, the
operation mode is not changed at the set time.
Short push to confirm the operation mode setting. The event time displays. Turn the
knob to set the time of the event and confirm by a short push. Then turn the knob to
select another event or long push and turn the knob to select another weekday.
After all desired events have been edited, long push to leave the time schedule settings.
The controller goes to the basic display mode also after 30 secs of user inactivity.

domat UC300 01/2019 Subject to technical changes. 5
Change of setpoints and controller time:
Switch to the settings mode with a super long push (>2.5 s). The controller switches to
settings mode (flashing thermometer icon).
Turning the knob selects between following settings:
-Controller time and day of week (Clock icon, Day of week)
-Setpoint temp. Heating Day mode (Temperature, Heating, Day are flashing)
-Setpoint temp. Heating Night mode (Temperature, Heating, Night are flashing)
-Setpoint temp. Heating Off mode (Temperature, Heating, Empty house are
flashing)
-Setpoint temp. Cooling Day mode (Temperature, Cooling, Day are flashing)
-Setpoint temp. Cooling Night mode (Temperature, Cooling, Night are flashing)
-Setpoint temp. Cooling Off mode (Temperature, Cooling, Empty house are
flashing)
Select the requested value by a short push. Turn knob to change value. Confirm by a
short push again.
If there is no user activity for 30 s, the controller goes to the basic display mode.
Default values:
Default values as well as all other settings (PI parameters, address, baud rate...) can be
set by the configuration program, ModComTool, and a USB/RS485 or RS232/RS485
converter –see Related products.
Display
A large (60 x 60 mm) display clearly shows
actual room temperature and controller
status with 7-segment digits and standard
Day, Night, Off, and Time scheduler
symbols. Active output is indicated by a
heating symbol. In the upper part, there
are week days used for time scheduler
setup. Other symbols are not used.
LCD symbol set

6 01/2019 Subject to technical changes. domat UC300
Connection
V thermic valve 24 V AC
B floor temperature sensor, Pt1000, e.g. domat HTF
Connection of power, communication, valve and floor sensor. Suitable cable types are
LAM DATAPAR 2x0.8 (cross-section in mm2), JYTY 2x1 (diameter in mm) etc. If
communication and power are in the same cable, use 4-core LAM DATAPAR 2x2x0.8,
JYTY 4x1. Up to 100-120 meters, parallel lines of 24 V and data bus are no problem.
Regarding to EMC it is better if the pairs are twisted, such as with the LAM DATAPAR or
Belden 8205 cable.
A terminal is designed for maximum 3 wires of 0.8 mm2. With cable types as above,
maximum (starting) power of the controller and valve of ca. 7 VA and acceptable
voltage drop of max. 15 %, the maximum cable length for 10 controllers is about 50 m.
If the controllers and valves are at higher distance than 50 m from the transformer or
more valves are connected to the transformer (max. 2 valves per controller), it is more
suitable to supply the controllers locally. The RS485 bus is galvanically separated and
connects all controllers, regardless of the way they are powered.
1
2
3
4
5
6
78
9
1
2
3
4
5
6
78
9
24 V ~
UC300
UC300 RS 485
V V
B B

domat UC300 01/2019 Subject to technical changes. 7
Dimensions
UC300
UC300/DK
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.

8 01/2019 Subject to technical changes. domat UC300
Changes in
versions
02/2015 —Changes in measuring ranges, configuration tool program, web pages for
downloading software and related products.
09/2016 —Changed the format and reference to the configuration software.
03/2017 —Added picture and description of the installation and link on the datasheet
with other colours.
10/2017 —Added Safety note, description UC300/DK version, change pictures.
05/2018 –Technical data change.
01/2019 –Technical data change.