Emerson SL-31080 specifications Description, Dimensions, Specifications, Termination

TEMPERATURE/HUMIDITY TRANSMITTER - WALL (4-20MA)

Description

The THW420 combination temperature/humidity transmitter is designed to meet applications that require local indication of both temperature and humidity in a single, aesthetically pleasing enclosure.

This device incorporates a 10K ohm (Ω) platinum RTD. The transmitter requires 24 VDC. The sensor provides an accurate and predictable four-wire, 4-20 mA output signal for temperature and a second 4-20 mA output signal for humidity.

Dimensions
FRONT	0.95"
VIEW	(241mm)
4.5"
(1143mm)
	Wall
2.25"	0.75"
(572mm)	(191mm)
	SIDE
	VIEW
2.75"
(699mm)
TOP VIEW

Specifications

Output	4 to 20 mA
Sensor	10K Ω platinum RTD
Supply Voltage	24 VDC
Tolerance of Resistance	±1.5°F (±0.83°C)
(Accuracy)	±2% RH (from 15 to 95% RH)
Response Time	20 seconds for a 63% step
Environmental Operating	45°F to 96°F; 0 to 100% RH
Range (Transmitter)	(7°C to 35°C); 0 to 100% RH

Termination

The THW420 transmitter must be powered from a 24 VDC supply. The combination temperature/ humidity sensor is terminated as follows:

•The humidity transmitter requires a three-wire termination for the 4-20mA output using 24 VDC.

•The temperature sensor also requires a three- wire termination. In most cases, it obtains power from the analog input to which it is connected and no external power is required.

Though interference from external sources is not a major problem with current transmitters, Liebert recommends separating the wiring from line voltage wiring and from wiring used to supply highly induc- tive loads such as motors, generators and coils. Lie- bert also recommends making power connections with twisted pair wire of at least 22 AWG and crimp- type connectors.

							Controller
	SW2 OUTPUT SELECT			To GND (common)				Ground
		ON		of controller*
	4-20ma	Ch1	0-5V		From +24VDC			4-20 mA
	4-20ma	Ch2	0-5V					Input #1
					of controller or
								+
	RESIST.	Ch3	0-5V		power supply		To controller’s
	RUN	%RH	CAL					-
							analog input
								4-20 mA
	SW2						(temperature signal,
								Input #2
							4-20mA)
								+
			C9 Gnd		Ch1	Ch2	To controller’s
				V+				-
			X				analog input
							(humidity signal,
			J2				4-20mA)
	DISPLAY CYCLE
	IN SECONDS						* NOTE:
		10	J3
	3		20	CAL	Temp	Temp	The GND (common)
	T		H Ch3				terminal is common
	POT1				R19		between the Power
		Building Automation				T&B	and Sensor
	U3	Products, Inc.
			Copyright 2000			SWITCH
			REV. 101600
			XCOMBO T&B		Short
			J1		Norm
					Open
						SW1	+24VDC should be
	RTH1 RTH2						used at all times
	Terminations
!	CAUTION
	Liebert recommends wiring the sensor
	WITHOUT power applied because
	accidental arcing may damage the product
	and will void the warranty.

Ordering Information

Quantity Part # Description

THW420 Combination Temperature/Humidity Transmitter Wall 4-20 mA @ 45°F to 96°F and 0 to 100% RH

SL-31080 Product Specification/Installation Sheet page 1 6/03 (Rev. 0)