Specification of Intrinsically Safe Temperature & Humidity Transmitter LFH71

Technical parameter

Intrinsically Safe Temperature and Humidity Transmitter with Probe LFH71
Relative Humidity
Sensor	Digital
Range	0%~100%RH
Output	4~20mA(two wire)
Accuracy	±3%@20°C & 20~80%RH
Response Time	≤15s (20°C, Slow flow air)

Relative Temperature

Sensor	Digital
Range	0~50°C，-20~60°C etc
Output	4~20mA(two wire)
Accuracy	±0.3°C@20'c, For other accuracy, refer to the digital sensor temperature accuracy curve below.

The digital sensor temperature accuracy curve

Intrinsically safe parameters

Explosion-proof Marking	With display: Ex ia IIC T6/T4 Ga Without display: Ex ia IIC T6/T4 Ga; Ex ia IIIC T200 85°C/T200 135°C Da
Explosion-proof Certificate	CE24.2060X
Intrinsically Safe Parameters	(RH+、RH-) : Ui : 28VDC; li : 93mA; Pi : 0.65W; Ci : 0.02uF; Li : 0mH (T+、T-) : Ui : 28VDC; li : 93mA; Pi : 0.65W; Ci : 0.02uF; Li : 0mH
Environment Temperature	T4 : -40°C~80°C; T6 : -40°C~60°C

Other parameters

Power Supply	9~28VDC
Maximum Power	0.04UV (W) (UV=supply voltage)
Output Load	≤500Ω
Display	Intrinsically safe: Optional LCD display (with unit without backlight) Dust intrinsically safe: No display
Housing Material	ADC12, stainless steel probe and sintered mesh filter
Working Temperature	T4: -40°C~80°C; T6: -40°C~60°C, 5%~95%RH (non-condensing)
Protection Class	IP65
Weight	≈666g(Wall-mounted) ≈760g(Duct type) ≈813g(Split type, without accereceries)
Certificates	CE,Intrinsically Safe Explosion-proof, Dust Intrinsically Safe Explosion-proof

WARNING

1.The product housing is made of aluminium alloy, please avoid the risk of ignition during use due to impact or friction.

2. The housing must be reliably grounded during installation.

3.The product display is made of plastic with a potential danger of electrostatic charge. Please avoid friction during use, or wipe

with a wet cloth when cleaning.

4. When the product is used in explosive dust environments, there is a potential danger of electrostatic charge, so it should not

be used in areas affected by charge-generating processes, mechanical friction, separation processes, electronic emission and

pneumatic transmission of dust.

ATTENTION:

1. Example LFH711-A4A4311B represents wall-mounted type, accuracy of ±3% RH (±0.3'C), humidity output 4-20mA,

Itemperature output 4-20mA, temperature range 0 ~ 50'C, with display;

2. When the temperature range is selected as 8, the temperature range specified by the customer shall not exceed the specified

range,T6: -40°C~60°C; T4: -40°C~80°C;

3. When the display is selected as showing (1), only intrinsically safe type (B) can be selected.

4. Prolonged exposure of the product's sensor probe to high concentrations of chemical gases may cause the sensor's

reading to shift.

Attention:

Expansion screws are required if mounted on the wal; machine screws are required if mounted on the iron plate.