1H/OT Outside Humidity and Temperature Sensor Data Sheet, 91-2677 Issue 3/B 4/11/98

Data Sheet

H/OTOutside Humidity and Temperature Sensors

OUTSIDE HUMIDITY AND

TEMPERATURE SENSORS

H/OT H/OT/RS

Description

Relative humidity and temperature sensors for outside airmeasurement applications, providing high quality humiditysensing combined with temperature monitoring. Resistive bulkpolymer technology offers excellent linearity and stability overtime especially in high R.H. conditions. Matched diode temperaturecompensation maintains accuracy over the operating range.Two versions are available, one for the north facing wall mounting,the other for roof mounting with a radiation shield to avoid solar,rain and wind effects. Electronics are mounted in an IP67 housingwith M20 conduit entry.

H/OT - wall mounted version.H/OT/RS - radiation shield version; mast or wall mounting.

85 m

m57

mm

180 mm

Features

• Resistive bulk polymer technology• Resistant to surface contamination• Precalibrated for ease of commissioning• IP67 housing• 2 part connectors for ease of installation• Radiation shield reduces solar, rain and wind effects

Physical

180

mm

150

mm

85 mm

94 mm

Mast mountingbracket

M20 glandmast Ø 50 mm max

H/OT Outside Humidity and Temperature Sensor Data Sheet, 91-2677 Issue 3/B 4/11/98

H/OT Outside Humidity and Temperature Sensors Data Sheet

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FUNCTIONALITYThe sensor contains a resistive bulk polymer relative humidity sensing element, and a thermistor temperature sensing element. Thehumidity signal is converted to a 4 to 20 mA signal by the sensor electronics.

INSTALLATIONThe H/OT sensor should be located in a relatively sheltered environment, out of direct sunlight, preferably on a north facing wall. TheH/OT sensor should be mounted so that the slots in the solar shield point downwards. The H/OT/RS should be mounted so that the'beehive' is vertical.

The installation involves:choose locationfor H/OT drill pilot hole

fix in positionfor H/OT/RS insert probe in shield gland

mount on wall using screws ormount on mast using straps

remove sensor lidfeed IQ cable through glandwire cablessetup IQ channels for current (I)configure IQ sensor modulestest sensor

Full installation details are given in the H/OT Installation Instructions, 91-2838, and the H/OT/RS Installation Instructions, TG200167.

H/OT Outside Humidity and Temperature Sensor Data Sheet, 91-2677 Issue 3/B 4/11/98 3

Data Sheet H/OT Outside Humidity and Temperature Sensors

CONNECTIONS

FIELD MAINTENANCEThe removal of dust, and accuracy checking is covered in the H/OT Installation Instructions, 91-2838.

PRODUCT CODEH/OT Outside humidity and temperature sensorH/OT/RS Outside humidity and temperature sensor with radiation shield

IQ

3humidity

temperature

polarity independent

Sensor24VSIG

0VSIG

humidity

Terminate screensat IQ end only

temperature linked forthermistor (T)

linked forcurrent (I)

H/OT4

21

2 analogue input channels

4321

sensor PCB

H/OT Outside Humidity and Temperature Sensor Data Sheet, 91-2677 Issue 3/B 4/11/98

H/OT Outside Humidity and Temperature Sensors Data Sheet

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ytidimuH

T 001

B 051-

U 001

L 0

E 3

Trend Control Systems Ltd reserves the right to revise this publication from time to time and make changes to the content hereofwithout obligation to notify any person of such revisions or changes.

Trend Control Systems Ltd. P.O. Box 34 Horsham Sussex RH12 2YF England Tel:+44 (0)1403 211888 Fax:+44 (0)1403 241608 www.trend-controls.com

SPECIFICATIONS

Electrical

Humidity measuringrange :0 to 99 %RH non-condensingTemperature measuringrange :-40 to +50 °CHumidity element :Resistance change through bulk

polymerHumidity accuracy :± 3 %RH within range 20 to 90 %RH

including hysteresis, l inearity andrepeatability.

Temperature effecton RH :less than 0.11% per °CSensitivity :0.1 %RHHysteresis :less than 1 %Repeatability :0.5 %RHLong term stability :less than 1 % drift per yearTemperature element :Thermistor 10 kΩ at 25 °CTemperature accuracy :± 1 °CHumidity output signal :4 to 20 mA for 0 to 100 %RHTemperature outputsignal :Thermistor 10 kΩ at 25 °CSupply voltage :12 to 36 Vdc

Sensor ScalingThe IQ controller’s sensor type modules must be set up with thecorrect scaling as shown in the tables.

HumidityUse sensor type scaling mode 0, linear, and table below:

10V(A) All new IQ1 series (Hardware versions:IQ7xv3, IQ8xe,IQ91/93ev4, IQ92ev3, IQ10x+, IQ104+, IQ111+v3, IQ131+and all newer versions).

10V(B) All IQ2 and IQ1 series except new IQ1s (see 10V(A) above),those without thermistor links, and IQ90s.

LK/D Where LK/D link header is used, i.e. on IQs withoutthermistor links.

2.55V For IQ90 series controllers only.

TemperatureFor temperature scaling, select required temperature range andthen required IQ type.

Use sensor type scaling mode 2, linearise (thermistor volts), andthe table below:

Mechanical

DimensionsH/OT :180 x 85 x 57 mmH/OT/RS :irregular (see 'Physical' page 1)Mast diameter :50 mm maximum (H/OT/RS)

Fixing CentresH/OT :85 mmH/OT/RS :58 mm (square)

Cable entry :M20Material (H/OT)

Cowling :PVCHousing :Impact resistant ABS

Material (H/OT/RS)Probe :Stainless SteelHousing :Impact resistant ABSRadiation Shield :UV stabilised thermoplasticBracket :Aluminium

Connectors :2 part screw terminals for 0.5 to 5 mm² cable.Weight

H/OT :180 gmH/OT/RS :1065 gm

Environmental

Ambient limitstemp :-40 to +70 °Chumidity :0 to 99 %RH

Protection :IP67

C°05+otC°04- C°04+otC°01-

)A(V01 )B(V01 D/KL V55.2 )A(V01 )B(V01 D/KL V55.2

B 04- 04- 04- 04- 01- 01- 01- 01-

T 05 05 05 05 04 04 04 04

F 29.9 17.9 39.4 84.2 66.8 74.8 16.4 51.2

G 31.9 49.8 47.4 82.2 85.7 24.7 3.4 98.1

H 33.7 71.7 22.4 38.1 42.6 11.6 38.3 65.1

I 38.4 37.4 92.3 12.1 38.4 37.4 82.3 12.1

J 17.2 56.2 71.2 86.0 55.3 84.3 66.2 98.0