FTS THS-3 User manual

1.800.548.4264
www.ftsenvironmental.com
700-THS3 Rev. 6 –05 May 2015
THS-3
Temperature and Humidity Sensor
Installation and Quick Setup Guide

1.800.548.4264
www.ftsenvironmental.com
700-THS3 Rev. 6 –05 May 2015
Contact information
FTS
1065 Henry Eng Place
Victoria, B.C., V9B 6B2
CANADA
www.ftsenvironmental.com
Toll-free
1-800-548-4264
Local
250-478-5561
Technical support
http://support.ftsenvironmental.com

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Table of Contents
Contact information .................................................................................................................................................1
Chapter 1 Introduction................................................................................................................................. 3
1.1 General Description .............................................................................................................................................3
1.2 Specifications..........................................................................................................................................................4
Chapter 2 Installation and Maintenance................................................................................................5
2.1 General......................................................................................................................................................................5
2.2 Tower Mounting....................................................................................................................................................5
2.3 Maintenance ...........................................................................................................................................................7
Chapter 3 Sensor Quick Setup Guide ...................................................................................................... 9
3.1 Configuring the THS-3.........................................................................................................................................9
3.2 In-line Logging.................................................................................................................................................... 11
3.3 Regular Logging ................................................................................................................................................. 11
3.4 Confirm Sensor Operation.............................................................................................................................. 13
3.5 Changing the Setup .......................................................................................................................................... 14
Document Revision History .................................................................................................................................15

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Chapter 1 Introduction
1.1 General Description
The THS-3 is a combined analog Temperature and Relative Humidity sensor. Temperature is sensed
by an encapsulated thermistor housed in a stainless steel tube. Thermistor contacts are brought
directly to the sensor connector for easy temperature measurement. Relative Humidity is measured
using a capacitive-type humidity transducer. A microprocessor internal to the THS-3 sensor measures
the transducer humidity, performs the appropriate conversion, and outputs a voltage proportional to
the relative humidity (0 to 1 Vdc equals 0 to 100% RH) on the sensor connector.
The T/H sensor assembly (see Figure 1-1) houses the sensors and associated electronics. Both sensors
are protected from air-borne contaminants by a replaceable sensor filter. The sensor assembly is
mounted to an anodized aluminum base and housed inside white louvers that make up the solar
screen. The purpose of the screen is to prevent solar heating of the sensors that would introduce
large inaccuracies in the data. At the same time, airflow is permitted to aid in correct ambient
readings.
The sensor is mounted on an aluminum sensor support arm that can be attached to a mast or tower.
Figure 1-1: THS-3 Temperature and Humidity Sensor –Exploded View
Solar Screen
T/H Sensor Filter
T/H Sensor
T/H Sensor Cable Interface
Support Arm
U Bracket and Bolts

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1.1.1 Connections
The THS-3 sensor connector is an environmentally sealed, bayonet mount, keyed, military style
connector. This connector is waterproof even without a mating connector attached. Electrical signal
connections for the THS-3 connector are shown in the table below.
PIN
SIGNAL
B
Power (+12Vdc nominal)
C
Chassis Ground
D
Humidity Output (0-1Vdc for 0-100% RH)
F
Temperature Output (thermistor +)
J
Ground (Power & Humidity Output)
K
Temperature Ground (thermistor -)
others
No Connect
Table 1: THS Sensor Signal Connections
1.2 Specifications
The specifications for the THS-3 Temperature and Humidity Sensor are shown in Table 2.
General
Operating Temperature: -40 to 60°C
Operating Humidity: 0 to 100% RH
Operating Voltage: 9.6 to 20 Vdc, 12 V nominal
Operating Current: less than 1 mA
Measurement Speed: less than 50 ms
Temperature
Type: Encapsulated Thermistor
Output: 10k ohm @ 25°C
Accuracy: +/- 0.1°C (0 to 60°C)
Resolution: 0.1°C
Humidity
Type: Capacitive Sensor
Output: 0 to 1 Vdc
Resolution: 1%
Accuracy: +/- 2% (0 to 100% RH)
Filter
High Density Polyethylene
Pore size: 35 microns
Hydrophobic
Table 2

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Chapter 2 Installation and Maintenance
2.1 General
In order to install the THS-3, the following equipment will be needed:
a) a 5/16” hex wrench for attaching the THS to the support arm mount;
b) a ¼ “ wrench to tighten the U-Bolt assembly; and
c) cable ties to attach the cable to the tower assembly.
Prior to installation observe the site and ensure the following can be achieved for optimum
performance of the sensor:
a) The sensor should be in the open, in a shade free area to ensure
accurate temperature readings.
b) The sensor should be well away from external sources of heat (i.e. any
equipment at the site that might generate heat).
c) The sensor support arm should be levelled (tower mount should be
levelled).
2.1.1 Installation Height
Correct installation height is dependent on regulations for the jurisdiction in which the equipment is
to be deployed. Ensure you review local regulations prior to installation.
In the United States the THS-3 Temperature & Humidity sensor is to be installed on the south side of
the mast 4 to 8 feet above ground. The Canadian regulations are to install the sensor on the south
side of the mast 1 to 1.3 meters above the ground.
Sensor height is also dependant on regional weather conditions. The sensor should be installed at a
height that is above the worst case estimate for snow levels in the area.
2.2 Tower Mounting
The procedure for tower mounting the THS-3 is as follows:
1. Remove the locking screw from the support arm mount and then slide the THS-3
assembly support arm mount (Figure 2-1). If the sensor is deployed in a coastal or
otherwise corrosive environment, lubricate the locking screw with white lithium grease
to prevent seizing. Secure the assembly with the locking screw.

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Figure 2-1: Attaching the assembly to the support arm
2. Loosely attach the support arm to the mast or tower with the clamp bolts at the
desired sensor height. Ensure the support arm’s “V” is fitted to the pole.
Figure 2-2: U-Bolt assembly and support arm attachment

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3. In the northern hemisphere, position the support arm so that the sensor is positioned south
of the mast and on the north side of the solar panel to ensure neither pieces of equipment
will be shaded. In the southern hemisphere, the positioning will be opposite.
Figure 2-3: Support arm positioning (northern hemisphere)
(Note: support arm may not appear exactly as shown)
4. Attach the sensor cable to the support arm and the mast using cable ties.
5. Connect the sensor cable to the data logger’s Temperature / Humidity connector (red ring).
NOTE: Key Installation Points:
a) The sensor should be in the open, in a shade free area to ensure
accurate temperature readings.
b) The sensor should be well away from external sources of heat (i.e. any
equipment at the site that might generate heat).
c) The sensor should be given a minimum of thirty minutes to acclimatize
to a site after installation before data is taken.
2.3 Maintenance
FTS recommends that the sensor be returned to FTS for a yearly check of the THS-3 sensor’s
calibration.
Also, FTS recommends that during any site visit a visual check of the THS-3 cable, connector and
sensor filter is performed. Any observable damage should be noted so that the appropriate repairs
can be performed. The THS-3 sensor filter (FTS part number: 03-THS3-6192) is field replaceable in the
event that the sensor filter is clogged.
Please contact FTS technical support if the unit ceases to operate properly.
Solar Panel

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2.3.1 Inspecting and Replacing the Filter
To inspect the THS-3 filter, you must first remove the sensor from the housing assembly.
a) Remove any cable ties which will prevent the sensor from being removed from the
housing being careful not to damage the cable
b) Use a 5/8” Allen key to remove the three bolts securing the base of the sensor to
the base plate of the housing assembly.
Figure 2-4: Sensor base showing bolts
c) Gently remove the sensor and inspect the filter for cleanliness.
d) If the filter requires replacing, unscrew the white filter and replace it with a new
one, being careful not to touch or contaminate the inner sensors.
Figure 2-5: THS showing filter on and filter off
e) Replace the sensor in the housing assembly, tightening all bolts and replacing
cable ties as necessary.
Filter
Sensor base with bolts

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Chapter 3 Sensor Quick Setup Guide
This chapter will take you through the steps to set up (configure) the THS3 with an Axiom datalogger.
It is meant as a quick reference. Detailed instructions can be found in the Axiom User Guide and
Axiom Configuration Reference.
NOTE: After installation, the sensor should be given a minimum of thirty minutes to
acclimatize to a site before data is taken.
3.1 Configuring the THS-3
1) Connect the THS-3 to the data logger on the red Temperature and Humidity port.
2) From the data logger’s home page, select the Sensors icon.
Figure 3-1: Home Page
The next screen (SDI Sensor Mapping) will display the icons of the dedicated sensors which
are already added and set up.
3) To add the THS-3, select the Add icon, then press on the Air icon.
Figure 3-2: Adding the THS-3

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4) The Air Sensor Setup screen will be displayed:
Figure 3-3:
5) Edit the fields by pressing on the field box:
Sensor: The default name for the sensor is THS. You can change this if desired.
Active: This box must be checked in order for the sensor to collect data
Temp: This is the air temperature. The default name is ATC. You can change
this if desired. The default units of measurement is Celsius (C). To
change to degrees Fahrenheit, select the (F) radial button.
Humidity: This is the relative humidity.
Clip at 0% & 100%: If checked, causes the datalogger to limit humidity values read from
the sensor to the range of 0 to 100%. That is, any air sensor humidity
measurements above 100% are reported as 100% and any
measurements less than 0% are reported as 0%.
If the Clip at 0% & 100% is not enabled and the sensor reads outside of
its range (higher than 117%) then an error (ERR) will be reported.
6) Select OK .
i) If In-line Logging is enabled (from Station<Advanced<Edit<In-line Logging) the In
Line Logging screen will be displayed. Go to Section 3.2;
ii) If In-line Logging is not enabled, you will be returned to the Sensors screen. Go
to Section 3.3.

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3.2 In-line Logging
In order to view and collect data on a variable, it must be logged. In-line Logging provides the user an
option to set up simplified Logging and add variables to Current Conditions from the Sensor Setup
screen . However, In-line Logging does not have the full functionality of regular logging using the
functions in the Data screens. Logging of the variables will be in accordance with the sensor read
times and no logging offset can be input. Additionally, although In-line Logging can be viewed
through the Data functions, it can only be amended through the WindSonic Sensor Setup screen.
NOTE: In-Line Logging does not have the full functionality as setting up Logging
through the Data screen.
1) Select the Edit button , then Input the desired the Logging Interval (press on the hour,
minute, or second box to highlight it in blue and use the arrows to select the value).
Figure 3-4: In-line Logging Setup
2) Check Enable Logging and if you want these values to be displayed in Current Conditions,
check the Current Condition box. The logging interval will now be displayed in green in the
Logging Intervals screen (Data>Setup).
3) Select OK. Return to the Home Page
3.3 Regular Logging
If the In-line Logging option was not used, you must set up logging in order to view and collect data
on a variable. Regular logging provides the user the ability to create more complex logging than that
offered by the In-line Logging option.
1) From the Home page, select the Data icon and then the Setup Cog.

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Figure 3-5: Regular Logging
2) The Logging intervals screen will be displayed. If there are already logging intervals set up
they will be seen here. Logging intervals created through the Data functions, as described here, are
displayed in blue. Logging intervals created using the In-line Logging feature are displayed in green.
Figure 3-6: Logging Intervals
3) Press the Add icon, then the Edit icon. Set the desired logging interval and offset times.
NOTE: Logging intervals should not be less than the input measuring interval.
4) Scroll down the list of the Available Variables. Press on ATC and then use Move Right Arrow to
shift it to the Logged Variables field. Do the same with the RH variable.

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Figure 3-7
5) Once done, select OK and the new Logging interval will be displayed in the Logging Interval
page. Return to the Home page.
3.4 Confirm Sensor Operation
Now that the THS-3 is setup, confirm its operation and ensure data is being logged.
1) From the Home page select the Data icon to display the Data Status screen. Then select the
Table icon.
Figure 3-8: View Data
2) If the temperature and humidity variables are not displayed, use the arrow or the scroll bar
until they come into view. Data will be displayed.

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Figure 3-9: WindSonic Data
3) Return to the Home page.
3.5 Changing the Setup
If you want to change the setup, from the Home page select the blue Sensors icon, then select the THS
icon. Select the Set up Cog which will bring you to the THS Sensor Setup page. Press on the Edit
icon and make desired changes (see Section 3.1 paragraphs 4-6).

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Document Revision History
Revision
Date
Description
1
27 Jul, 2006
Original release
2
2 Oct, 2006
Updated specifications.
3
25 Jan, 2007
Added special order specification.
4
11 Oct, 2007
Updated for new filter, updated specifications.
5
27 Apr, 2015
Format change. Updated pictures. Added Quick Setup Guide.
6
5 May, 2015
Minor corrections