HONEYWELL TF428WNM/U (WHITE) (Modbus RTU) COMMUNICATING DIGITAL THERMOSTAT (220/230VAC, 50/60HZ)
Note
TF428WNM & TFM428KNM are interchangeable, they do the same thing.
General
The TF428WNM/U communicating thermostat is designed for 3-speed fan and valve control in a fan coil system, including:
2-pipe cool only/heat only/manual changeover
4-pipe cool /heat manual / automatic changeover
Ventilation mode
Manual or automatic 3-speed fan control
Water valve on/off control
The TF428WNM/U is available in Modbus RTU protocol and can be easily integrated into building automation system.
Features
RS485 interface in Modbus RTU slave mode
RS485 interface in Modbus RTU slave mode
Memorized time off
Cycle Per Hour (CPH)
Random startup
LCD display with simple user interface
Room temperature or setpoint temperature display selectable
Manual or automatic fan speed selectable
Temperature units in either °C or °F
User setting can be stored when power loss
Freeze protection function available
Keypad lock options
Specifications
Physical Layer EIA485
Protocol Modbus RTU
Baud rate 4800/9600(Default)/19200
Parity None
Error Checking Mechanism CRC
Rated Power & Frequency 220/230VAC, 50/60Hz
Power consumption <2W
Control PI, On/off output
Accuracy ±1°C at 21°C
Auto Cycle times 100,000 times
Manual Cycle times 10,000 times
Protection class IP20
Set point range 10 ~ 32°C
Display range 0 ~ 37°C
Ambient operating limits 0~ +49°C
Ambient storage limits -30 ~ +60°C
Humidity limits 5~90% RH, non-condensing
Action Type: 1
Pollution Degree 2
Protection against electric shock class Class II
Electronic control software class Class A
Rated Impulse Voltage: 2500V
Maximum Temperature for 155°C
Relay wiring
Wire Sectional area
(Recommendation) 1.0~1.5mm2
Applied altitude up to 2000m above sea level
Rating Capacity
Working current for the whole product : 4(3)A
4A: When the load of the thermostat is resistance
3A: When the load of the thermostat is inductance
For Fan load 3(2)A
3A:when the load is resistance; 2A:When the load is inductance
For Valve load 2(1)A
2A: when the load is resistance;1A: when the load is inductance
The valve need have overtravel-limit organ to turn off the
load.
Replacement For
HONEYWELL T9275A-V1 TERMOSTAT HONEYWELL T9275A-V1 TERMOSTAT
US 14136 
GB 10827 
AU 9892 
CA 9772 
VN 6749 
IE 5717 
NZ 4792 
BR 1799 
