Vaisala HUMICAP HMT100 User manual

Humidity and Temperature
Transmitter
HMT100
USER'S GUIDE
M210701EN-A
June 2005

PUBLISHED BY
Vaisala Oyj Phone (int.): [phone]
P.O. Box 26 Fax: [phone]
FIN-00421 Helsinki
Finland
Visit our Internet pages at http://www.vaisala.com/
© Vaisala 2005
No part of this manual may be reproduced in any form or by any means,
electronic or mechanical (including photocopying), nor may its contents be
communicated to a third party without prior written permission of the copyright
holder.
The contents are subject to change without prior notice.
Please observe that this manual does not create any legally binding obligations for
Vaisala towards the customer or end user. All legally binding commitments and
agreements are included exclusively in the applicable supply contract or
Conditions of Sale.

________________________________________________________________________________
VAISALA_____________________________________________________________________ 1
Table of Contents
CHAPTER 1
GENERAL INFORMATION............................................................................5
About This Manual...................................................................5
Version Information ............................................................... 5
Related Manuals ................................................................... 5
General Safety Considerations ............................................. 6
Feedback............................................................................... 6
Product Related Safety Precautions......................................6
ESD Protection.........................................................................7
Recycling ..................................................................................7
Trademarks...............................................................................7
License Agreement..................................................................7
Warranty....................................................................................8
CHAPTER 2
PRODUCT OVERVIEW..................................................................................9
Introduction to the HMT100 Humidity and Temperature
Transmitter................................................................................9
Product Description.......................................................... 9
Fixed and Remote Probe Models .................................. 10
Optional Display............................................................. 10
HMT100 Transmitter Components................................. 11
CHAPTER 3
INSTALLATION............................................................................................13
Mounting .................................................................................13
Wall Mounting ..................................................................... 13
With Plastic Wall Assembly Plate (Provided)................. 13
With Optional Aluminium Wall Installation Plate ............ 14
Installation with Rain Shield ................................................ 15
Installation with Radiation Shield ........................................ 16
Duct Installation Kit ............................................................. 17
Probe Assembly with Duct Installation Kit ................ 18
Drilling Instructions for Duct Installation Kit ................... 18
Connections............................................................................19
CHAPTER 4
MAINTENANCE ...........................................................................................21
Replacing the HUMICAP® Sensor........................................21
Fixed Probe Model .............................................................. 21
Remote Probe Model .......................................................... 21
Removing and Fastening the Probe.....................................22

User's Guide ______________________________________________________________________
2 ________________________________________________________________ M210701EN-A
Fixed Probe Model ..............................................................22
Remote Probe Model ..........................................................22
Calibration and Adjustment...................................................23
Relative Humidity Adjustment Using the Push-Buttons ......24
Adjustment with HM70 ........................................................25
Field Checking and Adjustment Using a Calibrated
Reference Probe ............................................................26
One-Point Adjustment Using a Calibrator ......................26
Two-Point Adjustment Using a Calibrator ......................27
LiCl-NaCl Adjustment .....................................................28
Adjustment with HMI41 .......................................................29
Connections and Selecting the Calibrator Function.......30
Offset and Gain Adjustments .........................................31
HMI41 as a Reference Meter ....................................31
HMI41 as a Terminal.................................................32
Troubleshooting..............................................................34
Analog Output Tests ..............................................................35
CHAPTER 5
TROUBLESHOOTING..................................................................................37
Error Mode...............................................................................37
Technical Support ..................................................................37
Return Instructions ................................................................37
Vaisala Service Centers.........................................................39
CHAPTER 6
TECHNICAL DATA ......................................................................................41
Specifications .........................................................................41
Dimensions in mm (inches)...................................................45
List of Figures
Figure 1 Fixed Probe Model ...................................................................11
Figure 2 Remote Probe Model................................................................11
Figure 3 Plastic Wall Assembly Plate .....................................................13
Figure 4 Plastic Wall Assembly Plate with Aluminium Installation Plate 14
Figure 5 HMT100 Installation with Rain Shield.......................................15
Figure 6 Installation of the Humidity Probe with the Radiation Shield....16
Figure 7 Probe Installation with the Duct Installation Kit ........................17
Figure 8 Assembly of the Humidity Probe with the Duct Installation Kit.18
Figure 9 Drilling Instructions ...................................................................18
Figure 10 HMT100 Connection Board ......................................................19
Figure 11 cIsolated Current-Loop Wiring, dVoltage Output Wiring......20
Figure 12 Removing the Humidity Probe (Fixed Probe Model)................22
Figure 13 Removing the Humidity Probe (Remote Probe Model) ............23
Figure 14 Adjustment Buttons ..................................................................24
Figure 15 Location of the MI70 Probe and Cable Connector Ports..........25
Figure 16 Example of the MI70 Adjustment Menu ...................................27
Figure 17 Example of the MI70 Adjustment Mode Graph Display ...........27
Figure 18 Location of the HMI41 Calibration Connector ..........................29
Figure 19 Accuracy of Temperature Measurement ..................................42

________________________________________________________________________________
VAISALA_____________________________________________________________________ 3
Figure 20 Dimensions HMT100 Fixed Probe Model ................................ 45
Figure 21 Dimensions HMT100 Remote Probe Model............................. 46
List of Tables
Table 1 Manual Revisions ....................................................................... 5
Table 2 Related Manuals ........................................................................ 5
Table 3 Wiring Table ............................................................................. 20
Table 4 Common Problems During Adjustment and Their Remedies .. 34
Table 5 Relative Humidity Measurement Specifications ....................... 41
Table 6 Temperature Measurement Specifications .............................. 41
Table 7 Dewpoint Temperature (Calculated) Measurement
Specifications ........................................................................... 42
Table 8 Accuracy of Dewpoint Temperature Measurement.................. 42
Table 9 Operating Environment Specifications ..................................... 42
Table 10 Inputs and Outputs ................................................................... 43
Table 11 Mechanics Specifications ......................................................... 43
Table 12 Options and Accessories.......................................................... 44

User's Guide ______________________________________________________________________
4 ________________________________________________________________ M210701EN-A
This page intentionally left blank.

Chapter 1 ________________________________________________________ General Information
VAISALA_____________________________________________________________________ 5
CHAPTER 1
GENERAL INFORMATION
This chapter provides general notes for the manual and the product.
About This Manual
This manual provides information for installing, operating, and
maintaining the Humidity and Temperature Transmitter HMT100.
Version Information
Table 1 Manual Revisions
Manual Code Description
M210701EN-A This manual, 1st version, June 2005
Related Manuals
Table 2 Related Manuals
Manual Code Manual Name
M210185en-B Humidity Calibrator HMK15 User's Guide
M210297en-C Hand-held Humidity and Temperature Meter
HM70 User's Guide
M210316en-A HMI41 Indicator and HMP41/45/46 Probes
Operating Manual

User's Guide ______________________________________________________________________
6 ________________________________________________________________ M210701EN-A
General Safety Considerations
Throughout the manual, important safety considerations are
highlighted as follows:
WARNING Warning alerts you to a serious hazard. If you do not read and follow
instructions very carefully at this point, there is a risk of injury or
even death.
CAUTION Caution warns you of a potential hazard. If you do not read and
follow instructions carefully at this point, the product could be
damaged or important data could be lost.
NOTE Note highlights important information on using the product.
Feedback
Vaisala Customer Documentation Team welcomes your comments
and suggestions on the quality and usefulness of this publication. If
you find errors or have other suggestions for improvement, please
indicate the chapter, section, and page number. You can send
comments to us by e-mail: [email protected]
Product Related Safety Precautions
The Humidity and Temperature Transmitter HMT100 delivered to you
has been tested for safety and approved as shipped from the factory.
Note the following precautions:
CAUTION Do not modify the unit. Improper modification can damage the
product or lead to malfunction.

Chapter 1 ________________________________________________________ General Information
VAISALA_____________________________________________________________________ 7
ESD Protection
Electrostatic Discharge (ESD) can cause immediate or latent damage
to electronic circuits. Vaisala products are adequately protected
against ESD for their intended use. However, it is possible to damage
the product by delivering electrostatic discharges when touching,
removing, or inserting any objects inside the equipment housing.
To make sure you are not delivering high static voltages yourself:
- Handle ESD sensitive components on a properly grounded and
protected ESD workbench. When this is not possible, ground
yourself to the equipment chassis before touching the boards.
Ground yourself with a wrist strap and a resistive connection cord.
When neither of the above is possible, touch a conductive part of
the equipment chassis with your other hand before touching the
boards.
- Always hold the boards by the edges and avoid touching the
component contacts.
Recycling
Recycle all applicable material.
Dispose of batteries and the unit according to statutory regulations.
Do not dispose of with regular household refuse.
Trademarks
HUMICAP®is a registered trademark of Vaisala.
License Agreement
All rights to any software are held by Vaisala or third parties. The
customer is allowed to use the software only to the extent that is

User's Guide ______________________________________________________________________
8 ________________________________________________________________ M210701EN-A
provided by the applicable supply contract or Software License
Agreement.
Warranty
For certain products Vaisala normally gives a limited one-year
warranty. Please observe that any such warranty may not be valid in
case of damage due to normal wear and tear, exceptional operating
conditions, negligent handling or installation, or unauthorized
modifications. Please see the applicable supply contract or Conditions
of Sale for details of the warranty for each product.

Chapter 2 __________________________________________________________ Product Overview
VAISALA_____________________________________________________________________ 9
CHAPTER 2
PRODUCT OVERVIEW
Thank you for choosing the Vaisala HMT100 Humidity and
Temperature Transmitter. This chapter introduces you to its features.
The Vaisala range of relative humidity measurement instruments
covers all the applications from ventilation to process control in
demanding explosive areas. For more information about other Vaisala
relative humidity instruments, please contact your Vaisala
representative or visit www.vaisala.com.
Introduction to the HMT100 Humidity and
Temperature Transmitter
Product Description
Vaisala HUMICAP® Humidity and Temperature Transmitter
HMT100 measures relative humidity, temperature and dewpoint. It is
powered with a 10...35 VDC or 24 VAC input voltage and it outputs
an analog signal of either 4...20 mA, 0...1 V, 0...5 V or 0...10 V.
At order time the HMT100 transmitter can be configured to output
either one or two quantities in the following combinations:
- simple RH transmitter
- simple Tdtransmitter
- RT and T transmitter
-T
dand T transmitter
The following accessories are optionally available:

User's Guide ______________________________________________________________________
10 _______________________________________________________________ M210701EN-A
- Wall installation plate (aluminium)
- Duct installation kit
- Rain shield with installation kit
- Rain/solar radiation shield installation kit (for pole installation)
Fixed and Remote Probe Models
The HMT100 is available either with a fixed probe (0.1 m probe
cable) or a remote probe with different cable lengths (3/5/10 m cable
lengths, a 10 m extension cable is also available, see Table 12 Options
and Accessories on page 44).
The HMP100 relative humidity probe used in the HMT100 transmitter
is fully interchangeable. You can easily remove the probe and replace
it with a new one without having to adjust the transmitter.
Optional Display
The HMT100 is also available with an optional one-line display. The
display shows the measurement results of selected parameters in
selected units (selected at order time). The parameters are displayed in
turns one at a time. The display backlight is turned on and off with a
jumper on the transmitter electronics motherboard.

Chapter 2 __________________________________________________________ Product Overview
VAISALA____________________________________________________________________ 11
HMT100 Transmitter Components
side view with optional display without display
0505-169. 0505-170
Figure 1 Fixed Probe Model
The following numbers refer to Figure 1 above:
1 = Transmitter cover
2 = Probe cover
0505-338
Figure 2 Remote Probe Model
The following numbers refer to Figure 2 above:
1 = Probe cable
2 = HMP100 Probe
3 = Filter

User's Guide ______________________________________________________________________
12 _______________________________________________________________ M210701EN-A
This page intentionally left blank.

Chapter 3 _______________________________________________________________ Installation
VAISALA____________________________________________________________________ 13
CHAPTER 3
INSTALLATION
Mounting
Wall Mounting
With Plastic Wall Assembly Plate (Provided)
1. Attach the wall assembly plate to the wall with two screws.
2. Press the transmitter down so that it slides down along the rails
of the mounting plate.
0505-171
Figure 3 Plastic Wall Assembly Plate

User's Guide ______________________________________________________________________
14 _______________________________________________________________ M210701EN-A
With Optional Aluminium Wall Installation Plate
1. Attach the aluminium plate to the wall.
2. Attach the plastic wall assembly plate (provided) to the
aluminium plate with two screws.
3. Press the transmitter down so that it slides down along the rails
of the wall assembly plate.
0505-339
Figure 4 Plastic Wall Assembly Plate with Aluminium
Installation Plate
The following numbers refer to Figure 4 above:
1 = Plastic wall assembly plate (provided)
2 = Aluminium wall installation plate (optional accessory, see
order form)

Chapter 3 _______________________________________________________________ Installation
VAISALA____________________________________________________________________ 15
Installation with Rain Shield
The rain shield with installation kit includes a metal mounting plate
and a rain shield for the transmitter. Vaisala order code: 215109.
050505-340
Figure 5 HMT100 Installation with Rain Shield
1. Fasten the metal mounting plate to the wall or pole with screws
(see Figure 5 above).
NOTE !Note the arrow on the mounting plate. Attach the mounting plate
with the arrow pointing upwards.
2. Fasten the plastic wall assembly plate (provided) to the metal
mounting plate with three screws.
3. Fasten HMT100 Humidity and Temperature Transmitter to the
wall assembly plate by pressing the transmitter down so that it
slides down along the rails of the mounting plate.
4. Fasten the rain shield to the metal mounting plate with two (M6)
mounting screws.
NOTE Remove the rain shield before taking out the HMT100.

User's Guide ______________________________________________________________________
16 _______________________________________________________________ M210701EN-A
Installation with Radiation Shield
DTR502 with probe installation kit includes a rain/solar radiation
shield DTR502 and a plastic installation support for the humidity
probe. Vaisala order code: DTR502B. If you already have the
DTR502 shield and need only the installation support for the probe, it
is available with Vaisala order code: 210623.
1. Fasten the probe to the installation support with two cable ties
(items 3 and 4 in Figure 6 below).
2. Insert and attach the support to the radiation shield by tightening
the plastic nut (item 2 in Figure 6).
3. Attach the entire radiation shield/probe assembly to a pole mast
(pole mast diameter: 30...60 mm/1.2 ... 2.3") with the U-bolt and
support arm, see Figure 6.
1
2
3
4
5
6
0505-248
Figure 6 Installation of the Humidity Probe with the
Radiation Shield
The following numbers refer to Figure 6 above:
1 = DTR502
2 = Plastics nut
3, 4 = Cable tie
5 = Adapter DRW212054 (installation support)
6 = Probe

Chapter 3 _______________________________________________________________ Installation
VAISALA____________________________________________________________________ 17
Duct Installation Kit
The duct installation kit includes a plastic pipe with a flange. Vaisala
order code: 210710. To install the HMP100 probe with the duct
installation kit, drill a hole to the duct wall, assemble the probe to the
duct installation kit, slide the probe head through the hole, and attach
the flange to the duct wall with four screws. See pages 18 and 18 for
details.
24
L
1
0505-176
Figure 7 Probe Installation with the Duct Installation Kit
The following explanations refer to Figure 7 above:
1 = Tension screw
Distance L can be adjusted and locked in place with the tension screw.

User's Guide ______________________________________________________________________
18 _______________________________________________________________ M210701EN-A
Probe Assembly with Duct Installation Kit
2
1
3
0505-177
Figure 8 Assembly of the Humidity Probe with the Duct
Installation Kit
The following numbers refer to Figure 8 above:
1 = HMP100
2 = Duct installation kit
3 = Probe cable
1. Slide the probe cable through the duct installation kit plastic
pipe.
2. Attach the probe cable to the HMP100 Humidity Probe.
3. Attach probe assembly to the duct.
Drilling Instructions for Duct Installation Kit
42
1
2
3
Ø24Ø3.2
Drill the holes for the duct installation kit as
follows:
1. Use a 24 mm drill bit to drill a hole to
the duct wall for the humidity probe.
2. Drill holes for the duct installation kit
mounting screws around the hole in a
square arrangement, 42 mm apart from
each other. Use a 3.2 mm drill bit to
drill the holes for the mounting screws
(four ST4.2×16-C-Z DIN 7981
screws).
0505-178
Figure 9 Drilling Instructions