THIS MODEL IS INVALID 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 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
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