Lefoo Indoor Temperature Humidity Transmitter LFH21

Name: Indoor Temperature Humidity Transmitter LFH21
Brand: LEFOO INDUSTRIAL CO.,LTD.
Rating: 4.8 (50 reviews)

LFH21 series temperature and humidity controller is a product designed for indoor temperature and humidity detection and control. It has the advantages of small size, simple installation and convenient operation. It has special design for lightning surge, electrostatic discharge, group pulse, voltage resistance, etc., strong anti-interference ability, and alarm function. It can be widely used in places such as computer rooms, buildings, warehouses, etc. where temperature and humidity measurement and control are required.

Features

* Standard switch box installation method for easy use.

* Light and beautiful shell design, with LCD backlight to display dual temperature and humidity.

* Using imported high-precision sensors with good long-term stability and anti-interference ability.

* Optional passive temperature output.

* Temperature and humidity offset can be set to facilitate customer on-site operation.

* CE certification, ROSH

* With relay and alarm function

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Transmitter

Pump

Specification
Features
Applications

Specification of Indoor Temperature Humidity TransmitterLFH21

Technical parameter

LEFOO Indoor Temperature and Humidity Transmitter LFH21
Relative Humidity
Sensor	Digital type
Range	0%~100%RH
Output	RS485/Modbus,0~10VDC
Accuracy	±3%@ 20℃ & 20~80%RH
Response time	≤10s (20℃, slow flow air)
Temperature
Sensor	Digital or passive thermal resistor, details refer to selection table
Range	0~50℃, -20~60℃, etc
Output Signal	RS485/Modbus,0-10VDC
Thermal Resistance	Details in selection table and thermal resistance graduation table
Accuracy	Digital sensor: ±0.3℃@20℃, See table below ; Passive thermal resistance: typical ±0.2~0.4℃@25℃, refer to selection table
Power Supply	RS485:15-35VDC/24VAC±20%	Voltage:15-35VDC/24VAC±20%
	Note: when RS485 and voltage type uses AC power supply, an isolation transformer is required Output load
Output Load	≥10kΩ(voltage output)
Display Accuracy	0.1℃,0.1%RH
Display and buttons	LCD display and keys with unit display and backlight
Alarm Function	1xBUZZER,1xLED
Relay	2 x SPST, 3A / 30VDC, 3A / 250VAC
Shell Material	PC
Working Environment	-20~60℃, 5%-95%RH (Non-condensing)
Protection Grade	IP30

Features of Indoor Temperature Humidity Transmitter LFH21

Standard switch box installation method for easy use.
Light and beautiful shell design, with LCD backlight to display dual temperature and humidity.
Using imported high-precision sensors with good long-term stability and anti-interference ability.
Optional passive temperature output.
Temperature and humidity offset can be set to facilitate customer on-site operation.
CE certification, ROSH
With relay and alarm function

Applications of Indoor Temperature Humidity Transmitter LFH21

Widely used in:

Comouter rooms
Buildinas
Warehousing
Places required temperature and humidity measurement and control .

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