LFH71 is a temperature and humidity transmitter that can be applied in hazardous occasions.
The product adopts cast aluminum housing with high protection level, which is suitable for the monitoring of natural gas pipeline network, air supply system of power plant, pharmaceutical factory clean room and other industrial environments with complicated working conditions.
The product adopts imported temperature and humidity sensors, with high precision and fast response.
The product is divided into intrinsically safe explosion-proof (with display), intrinsically safe dust explosion-proof two models, of which intrinsically safe explosion-proof can work in Zone 0, Zone 1, Zone 2; intrinsically safe dust explosion-proof can work in Zone 20, Zone 21, Zone 22.
| RELATIVE HUMIDITY | |
| Sensor | Digital |
| Measuring Range | 0%~100%RH |
| Output | 4~20mA(two wire) |
| Response Time | ≤15s (20°C, Slow flow air) |
| Accuracy | ±3%@20°C & 20~80%RH |
| RELATIVE TEMPERATURE | |
| Sensor | Digital |
| Range | 0~50°C,-20~60°C etc |
| Output | 4~20mA(two wire) |
| Accuracy | ±0.3°C@20'c (Refer Accuracy Curve Chart) |
| SAFETY 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 |
| 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.

1. Example LFH711-A4A4311B represents wall-mounted type, accuracy of ±3% RH (±0.3'C), humidity output 4-20mA, temperature 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.
More detail about Excel Test Sdn Bhd
Malaysia