Get humidity and temperature readings with the LPN-H

The LPN-H is a complete relative humidity and temperature current loop sensing module, with two independent loop powered 4~20mA outputs, one for Humidity (0~100%RH) and one for temperature (0~100°C).

The LPN-H comes in a wall mount or a duct mount version.

Both versions come complete in an industrial standard aluminium connection head. The digital relative Humidity sensor and Temperature sensor protrude from the head inside a protective cap. This cap allows air to circulate to the sensors while protecting them from physical harm.

Features

• Dual 4~20mA Outputs
• Sensirion SHT25 Digital Humidity sensor – Factory calibrated
• Long term stability
• Fast response: 4 seconds from 0 to 100%RH under ideal conditions
• Pt100 RTD Temperature Sensor
• Temperature Output Linearised
• Very Compact Design
• High Accuracy
• Low Cost
• Easy to Install
• Reverse Polarity Protection
• Wide Power Supply Range
• Rugged and reliable

 

LPN-H Common Specifications
Output		2 wire 4~20mA (Loop Powered).
Power Supply		9~33Vdc.
Supply Voltage Sensitivity		<±0.01%/V FSO.
Maximum Output Current		Limited to <32mA
Max output Load Resistance		800Ω @ 24Vdc. (50Ω/V Above 8Vdc).
Isolation Test Voltage		Between %RH and Temperature; 50Vdc for 1 min.
Operating Temperature		-30~70°C.
Storage Temperature		-30~85°C
Operating Humidity		100%RH. Non-condensing.
IP Rating		Sensor = IP51, Terminal Case = IP68. See Note 2 on page 2.
LPN-H %RH Transmitter Specifications
Accurate to		±2% FSO Typical 10~80%RH non condensing
	-Important	For continuous measurements of ≥90%RH, refer to operating range in brochure
Ambient Temperature Drift		<±0.05%/C FSO Typical.
Humidity Sensor	-Hysteresis	±0.8% of Span Typical.
	-Linearity	±0.5%RH Typical.
	-Repeatability	±0.5%RH Typical.
	-Long Term Drift	±1%RH Typical at 50%RH in 5 years.
	-Output	0~100%RH for 4~20mA.
LPN-H Temperature Transmitter Specifications
Accurate to		<±0.1% FSO Typical + sensor Error
Linearity and Repeatability		<±0.1% FSO Typical + sensor Error
Ambient Temperature Drift		<±0.02%/C FSO Typical + sensor Drift.
RTD Sensor		Pt100 RTD, Class A Din 43760, IEC60751.
Sensor Current		1.0mA.
Sensor Output		0~100°C for 4~20mA factory calibrated. Output will stay at 4mA or 20mA if temperature low or high. 3mA output indicates faulty sensor.

Note 1: The inside of the head with the electronics board must not get wet.
Note 2: Good airflow and good air mixing must be maintained over the sensor to minimise local temperature fluctuations, and to ensure accurate measurements.