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Specification of Temperature and Humidity Transmitter with Display LFH30

LEFOO Temperature and Humidity Transmitter with Display LFH30
Relative Humidity		Temperature
Sensor	Humidity Sensitive Capacitor	Sensor	Pt1000 or passive thermal resistance ,see Order Ref No.
Range	0%~100%RH	Range	0~50℃, -20~60℃ etc
Output	RS485/Modbus, 0~10VDC, 4-20mA	Output	4-20mA, 0-10VDC, RS485/Modbus Optional
Accuracy	±2%@ 20℃ & 20~80%RH	Work Environment	-20~60℃, 5%-95%RH (Non-condensing)
Response time	≤10s(20℃,slow air flow)	Thermal resistance	See Order Ref No. and Thermal Resistance Indexing Table
Product installation type	LFH301 Wall-mounted type	Output Load	≤500Ω(Current type), ≥2KΩ(Voltage type)
		Accuracy	Digital sensor: 0.3℃ @ 5~60℃; Thermal resistance type: typical: ±0. 2~0. 4℃@25℃; see Order Ref No.
Product installation type	LFH302 Duct type	Display	LCD display optional, with unit display and backlight (4-20mA without backlight)
		Power supply	RS485 type: 9~35VDC/24VAC+20%	Voltage type: 12-35VDC124VDC+20%
Product installation type	LFH303 Split type		Curent type: 19.5~35VDC (RL=500Ω) /9.5-35VDC (RL=00)
		Protection Grade	IP65
		Shell Material	PC housing, PC probe and polymer filter (optional stainless steel prcbe rod, sintered / stainless steel wire mesh fiter)

ORDER REF NO.
Code and description									Remark
LFH301-	Wall-mounted type temperature and humidity transmitter								Model
LFH302-	Duct type temperature and humidity transmitter

LFH303-	Split type temperature and humidity transmitter
	2	±2%RH(0.3℃)							Accuracy range
		V10	0~10VDC (3-wired)						Humidity output
		A4	4~20mA (2-wired)
		RS	RS485/Modbus
			V10	0~10VDC(3-wired)			0	PT1000, ±2℃@0℃	Temperature output
			A4	4~20mA(2-wired)			1	PT100, ±2℃@0℃
			RS	RS485/Modbus			2	NTC20K, ±4℃@25℃
							6	NTC10K, ±4℃@25℃
				0	NO				Temperature range
				1	0~50℃
				2	minus 20℃~60℃
				8	Others (customer specified)
					0	No display			Display mode
					1	LCD display
LFH301-	2	A4	A4	1	1				Selection example

1. Only when the temperature output option is V10 or A4, the corresponding temperature range 1-8 should be selected; otherwise, only 0 can be selected.

2. Model example LFH301-2A4A411 represents the Wall-mounted type, accuracy 2%RH (0.3°C), humidity output 4-20mA, temperature output 4-20mA,

and temperature range 0-50°C with display.

3. Exposure of the sensor probe of this product to high concentrations of chemical gases for a long time may cause the reading of the sensor to shift.

4. When selecting a metal rod temperature and humidity transmitter, the specifications of the metal rod and front cover should be specified.