Vaisala HUMICAP HMT360 SERIES, HUMICAP HMT361, HUMICAP HMT363, HUMICAP HMT364, HUMICAP HMT365 User Manual

USER’S GUIDE

Vaisala HUMICAP® Humidity and

Temperature Transmitter Series HMT360

M010056EN-I

PUBLISHED BY

Vaisala Oyj Phone (int.): [phone]
P.O. Box 26 Fax: [phone]
FI-00421 Helsinki
Finland

Visit our Internet pages at www.vaisala.com
© Vaisala 2011
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.

________________________________________________________________________________

Table of Contents

CHAPTER 1

GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Contents of This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Version Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Documentation Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

ESD Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

Regulatory Compliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

EU Declaration of Conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

License Agreement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

CHAPTER 2

PRODUCT OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Introduction to HMT360 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Output Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Probe Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

CHAPTER 3

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

General Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Mounting the Probe Cable in Gas Group IIC Spac es . . . . . . . . . . . . . . . . . . . . . . . . . 19

Selecting Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

General Instructions for Probes with Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Checking the Temperature Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Mounting the Transmitter Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Probe Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

HMP363 for Confined Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

HMP363/365/367 Duct Installation Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

HMP364 for High-Pressure Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

HMP365 for High Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

HMP367 for High Humidities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

HMP368 for Pressurized Pipelines or Moisture in Liquids . . . . . . . . . . . . . . . . . . . . . 30

Tightening the Clasp Nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Installing the HMP368 Probe Through a Ball Valve Assembly. . . . . . . . . . . . . . . 32

Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Installation in Hazardous Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

VAISALA________________________________________________________________________ 1

________________________________________________________________________________

US and Canadian Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

European Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

CATEGORY 1 (Zone 0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

CATEGORY 2 or 3 (Zone 1 or 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Maximum Cable Resistance Calculation for the Barrier (Vaisala Order Code:

210664) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

HMT360 Connected to a Galvanic Isolator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

HMT360 Connected to a Zener Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Examples of Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Grounding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

CHAPTER 4

OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

Local Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

Power ON/OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

HMT360 with Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

HMT360 without Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

DIP Switch Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Display/Keypad Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Setting the Pressure for Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Selecting Output Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Upper Half of Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Lower Half of Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Selecting Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Scaling Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50

Serial Communication Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Setting the Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

ASEL Selecting Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

S Scaling Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Adjustment Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52

CRH Relative Humidity Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

CT Temperature Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Output Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

ITEST Testing Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

SEND Outputting Measurement Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

R Activating Continuous Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

S Stopping Continuous Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

INTV Setting Output Interval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

PRES Setting Ambient Pressure for Calculations . . . . . . . . . . . . . . . . . . . . . . . . 55

FILT Output Filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Resetting the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

RESET Transmitter Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

CHAPTER 5

MEASURING AT OVERPRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Pressure Regulator Recommended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

CHAPTER 6

CALIBRATION AND ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

Calibration Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

Factory Calibration and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

2 _______________________________________________________________________________

________________________________________________________________________________

User Calibration and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Removing the Electronics Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Calculating Correspondence of Current Values and Output Quantities . . . . . . . . . 62

Relative Humidity Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Automatic Two-Point Adjustment (Only HMT360 with Display) . . . . . . . . . . . . . . . . . 63

Manual Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Low End Adjustment (HMT360 without Display) . . . . . . . . . . . . . . . . . . . . . . . . . 65

High End Adjustment (HMT360 without Display) . . . . . . . . . . . . . . . . . . . . . . . . . 66

Low End Adjustment (HMT360 with Display). . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

High End Adjustment (HMT360 with Display) . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

One-Point Temperature Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

ACAL Analog Output Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

CHAPTER 7

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Periodical Checking and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Transmitter Housing and Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

CHAPTER 8

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71

Operation Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Analog Output Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Product Returns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

CHAPTER 9

TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Relative Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Temperature (+ Operating Pressure Ranges) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Water Activity in Jet Fuel Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Calculated Variables (Typical Ranges) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

With HMP361 Probe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

With HMP363, HMP364, HMP365, HMP367 and HMP368 Probes. . . . . . . . . . . 75

Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Classification with Current Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Accuracy of Calculated Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Accuracy of Dewpoint Temperature °C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Accuracy of Mixing Ratio g/kg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Accuracy of Wet Bulb Temperature °C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Accuracy of Absolute Humidity g/m3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

VAISALA________________________________________________________________________ 3

________________________________________________________________________________

APPENDIX A

DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83

HMP361 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83

HMP363 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84

HMP364 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84

HMP365 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84

HMP367 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85

HMP368 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85

Mounting Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86

Rain Shield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86

Protection Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87

APPENDIX B

WIRING FOR INTRINSICALLY SAFE OPERATION, FM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89

APPENDIX C

WIRING FOR INTRINSICALLY SAFE OPERATION, CSA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91

APPENDIX D

CERTIFICATES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93

4 _______________________________________________________________________________

________________________________________________________________________________

List of Figures

Figure 1 HMT360 and Probe Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 2 Probe Options for HMT360 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 3 Horizontal Mounting of Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 4 Vertical Mounting of Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

Figure 5 Measurement Error at 100 %RH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Figure 6 Transmitter Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 7 Parts of the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 8 Installation of HMP363 Probe in Duct with Flange and Supporting Bar . . . 25

Figure 9 HMP364 Probe Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 10 Marking Nut and Fitting Screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 11 Cleaning the Tightening Cone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

Figure 12 Mounting HMP365 Probe in Duct or Channel . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 13 HMP368 Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 14 Sealing of Fitting Body into Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 15 Tightening the Clasp Nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 16 Installing the HMP368 Probe Through a Ball Valve Assembly . . . . . . . . . .33

Figure 17 HMT360 Connected to Galvanic Isolator . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Figure 18 HMT360 Connected to a Zener Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 19 STAHL 9160/13-11-11 (Galvanic Isolator) . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 20 STAHL 9001/51-280-091-141 (Zener Barrier) . . . . . . . . . . . . . . . . . . . . . . 41

Figure 21 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 22 Local Display/Keypad Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Figure 23 DIP Switch Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Figure 24 Detaching the Electronics Unit with Probe for Calibration

and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Figure 25 Connecting Power Supply and Multimeter for Calibration . . . . . . . . . . . . .61

Figure 26 Display Chart of the Automatic Adjustment Procedure . . . . . . . . . . . . . . . .64

Figure 27 Accuracy over Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Figure 28 VTT IECEx Certificate page 1/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Figure 29 VTT IECEx Certificate page 2/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Figure 30 VTT IECEx Certificate page 3/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Figure 31 VTT IECEx Certificate page 4/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Figure 32 VTT ATEX 028X Certificate page 1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Figure 33 VTT ATEX 028X Certificate page 2/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Figure 34 VTT ATEX 028X Certificate Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Figure 35 VTT ATEX 023X Certificate page 1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Figure 36 VTT ATEX 023X Certificate page 2/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Figure 37 FM Certificate of Compliance page 1/3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Figure 38 FM Certificate of Compliance page 2/3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Figure 39 FM Certificate of Compliance page 3/3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Figure 40 CSA Certificate of Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Figure 41 TIIS Certificate of Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Figure 42 PCEC Conformity Certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Figure 43 GOST Certificate of Conformity page 1/3 . . . . . . . . . . . . . . . . . . . . . . . . . 109

Figure 44 GOST Certificate of Conformity page 2/3 . . . . . . . . . . . . . . . . . . . . . . . . . 110

Figure 45 GOST Certificate of Conformity page 3/3 . . . . . . . . . . . . . . . . . . . . . . . . . 111

VAISALA________________________________________________________________________ 5

________________________________________________________________________________

6 _______________________________________________________________________________

________________________________________________________________________________

List of Tables

Table 1 Manual Revisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 2 Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 3 Output Quantities for HMT360 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 4 HMP368 Probe Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Table 5 Serial Communications Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Table 6 Pressure Conversion Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Table 7 Relative Humidity Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Table 8 Temperature Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74

Table 9 Water Activity in Jet Fuel Applications Specifications . . . . . . . . . . . . . . . . . 75

Table 10 HMP361 Calculated Variables Specifications . . . . . . . . . . . . . . . . . . . . . . . 75

Table 11 HMP363, HMP364, HMP365, HMP367& HMP368 Probes Calculated

Variables Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Table 12 Output Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Table 13 General Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Table 14 Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

VAISALA________________________________________________________________________ 7

________________________________________________________________________________

8 _______________________________________________________________________________

Chapter 1 ________________________________________________________ General Information

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 Vaisala HUMICAP® Humidity and Temperature
Transmitter Series HMT360.

Contents of This Manual

- Chapter 1, General Information: This chapter provides general notes
for the manual and the product.

- Chapter 2, Product Overview: This chapter introduces the features,
advantages, and the product nomenclature.

- Chapter 3, Installation: This chapter provides you with information
that is intended to help you install this product.

- Chapter 4, Operation: This chapter contains information that is
needed to operate this product.

- Chapter 5, Measuring at Overpressure: This chapter provides you
with important information concerning measurement in conditions
with pressure higher than the normal atmospheric pressure.

- Chapter 6, Calibration and Adjustment: This chapter contains
instructions for checking the calibration and adjusting this product.

- Chapter 7, Maintenance: This chapter provides information that is
needed in basic maintenance of the product.

- Chapter 8, Troubleshooting: This chapter describes common
problems, their probable causes and remedies, and contact
information.

VAISALA________________________________________________________________________ 9

User’s Guide______________________________________________________________________

- Chapter 9, Technical Data: This chapter provides technical data of the
product.

- Appendix A, Dimensions: This appendix contains parts drawings of
the transmitter housing, probes and some transmitter mounting
accessories with metric and nonmetric dimensions specified.

- Appendix B, Wiring for Intrinsically Safe Operation, FM: This
appendix contains the wiring diagram for intrinsically safe operation
approved by Factory Mutual (FM).

- Appendix C, Wiring for Intrinsically Safe Operation, CSA: This
appendix contains the wiring diagram for intrinsically safe operation
approved by the Canadian Standards Association (CSA).

- Appendix D, Certificates: This appendix contains copies of the EXi
intrinsically safe certificates issued for the HMT360 series.

Version Information

Table 1 Manual Revisions

Manual Code Description

M010056EN-I This manual. July 2011 - Updated

Appendix Appendix D, Certificates,

on page 93.

M010056EN-H Previous version. Updated

Appendix Appendix D, Certificates,

on page 93. Updated manual

calibration instructions.

Related Manuals

Table 2 Related Manuals

Manual Code Manual Name

M210185EN Humidity Calibrator HMK15 User's

Guide

10 ___________________________________________________________________ M010056EN-I

Chapter 1 ________________________________________________________ General Information

Documentation Conventions

Throughout the manual, important safety considerations are highlighted as
follows:

WARNING

CAUTION

NOTE

Safety

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 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 highlights important information on using the product.

The HMT360 series transmitter delivered to you has been tested for safety
and approved as shipped from the factory. Note the following precautions:

Ground the product, and verify outdoor installation grounding
periodically to minimize shock hazard.

CAUTION

VAISALA_______________________________________________________________________ 11

Do not modify the unit. Improper modification can damage the product or
lead to malfunction.

User’s Guide______________________________________________________________________

Recycle all applicable material.

Dispose of batteries and the unit according to statutory regulations.
Do not dispose of with regular household refuse.

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 an ESD workbench is not available, ground yourself to the
equipment chassis with a wrist strap and a resistive connection cord.

- If you are unable to take either of the above precautions, touch a
conductive part of the equipment chassis with your other hand before
touching ESD sensitive components.

- Always hold component boards by the edges and avoid touching the
component contacts.

Recycling

12 ___________________________________________________________________ M010056EN-I

Chapter 1 ________________________________________________________ General Information

Regulatory Compliances

EU Declaration of Conformity

The HMT360 series transmitters are in conformity with the provisions of
the following EU directive(s):

- ATEX Directive

- EMC Directive

- ROHS Directive
Conformity is shown by compliance with the following standards:

- EN 60079-0

- EN 60079-11

- EN 60079-26

- EN 61326-1: Electrical equipment for measurement, control and
laboratory use - EMC requirements - for use in industrial locations.

- EN 55022: Information technology equipment - Radio disturbance
characteristics - Limits and methods of measurement.

EC-type examination certificate number: VTT 09 ATEX 028X issue No:1.

Certifications

The certifications that have been granted to the HMT360 series, and the
accompanying safety factors, are listed in section Classification with

Current Outputs on page 77.

Copies of the certificates and wiring diagrams are provided in the
following appendices:

- Appendix B, Wiring for Intrinsically Safe Operation, FM, on page 89

- Appendix C, Wiring for Intrinsically Safe Operation, CSA, on page

91

- Appendix D, Certificates, on page 93

VAISALA_______________________________________________________________________ 13

User’s Guide______________________________________________________________________

Trademarks

HUMICAP® is a registered trademark of Vaisala Oyj.

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 provided by the
applicable supply contract or Software License Agreement.

Warranty

Visit our Internet pages for more information and our standard warranty
terms and conditions: www.vaisala.com/services/warranty.html.

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.

14 ___________________________________________________________________ M010056EN-I

Chapter 2 __________________________________________________________ Product Overview

CHAPTER 2

PRODUCT OVERVIEW

This chapter introduces the features, advantages, and the product
nomenclature.

Introduction to HMT360

Vaisala HUMICAP® Humidity and Temperature Transmitter Series
HMT360 contains reliable, microprosessor-based two-wire instruments
for measuring relative humidity and temperature in hazardous areas.

0606-003

Figure 1 HMT360 and Probe Types

WARNING

VAISALA_______________________________________________________________________ 15

In hazardous environments, the transmitters must always be connected
via galvanic isolators or Zener barriers.

User’s Guide______________________________________________________________________

Output Quantities

Vaisala HUMICAP® Humidity and Temperature Transmitter Series
HMT360 is available either with or without a local display and with one or
two current output channels.

Available output quantities are listed in the table below:

Table 3 Output Quantities for HMT360

Character Quantity Abbreviation Availability

0 relative humidity RH A, D
1 temperature T A, D, F, H
2 dewpoint

temperature
3 absolute humidity a D
4 mixing ratio x D
5 wet bulb

temperature
6mass

concentration of

water
7 water activity aw H, F
8 relative humidity

of saturation
9 saturation

temperature

Td D

Tw D

ppmw H

RS H

Ts H

The characters used to indicate availability in the table above:
A = Available for HMT360 standard version
D = Available for HMT360 with optional calculations
F = Available for HMT360 Moisture and Temperature in oil

transmitter

H = Available for HMT360 Moisture and Temperature in Jet Fuel

transmitter

16 ___________________________________________________________________ M010056EN-I

Chapter 2 __________________________________________________________ Product Overview

Probe Options

The HMT360 series has various options for probes and cable lengths (2 m,
5 m and 10 m). The available probe types are presented in the figure below.

0603-036

Figure 2 Probe Options for HMT360

The following numbers refer to Figure 2 on page 17:
1 = HMP361 probe for wall mounting
2 = HMP363 probe for tight spaces
3 = HMP364 probe for pressurized spaces up to 100 bars
4 = HMP365 probe for high temperatures up to 180 °C *) Flange

for HMP365 available as an option
5 = HMP367 probe for high humidities
6 = HMP368 probe for installations in pressurized pipelines up to

40 bars; features a pressure-tight sliding clasp nut

VAISALA_______________________________________________________________________ 17

User’s Guide______________________________________________________________________

18 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

CHAPTER 3

INSTALLATION

This chapter provides you with information that is intended to help you
install this product.

General Installation Instructions

Mounting the Probe Cable in Gas Group IIC Spaces

NOTE

The following applies only to installation within the EU!
The following instructions shall be followed to fulfil the specifications of

the EN50284 for nonconductive layer of the probe cable:

- Never mount or handle the probe cable when hazardous gases are
present.

- For achieving a conductive shield, cover the probe cable with
conductive material like metal or conductive tape or mount the probe
cable in a metal conduit.

- Assure that the conductive shield fulfils requirements of the standard
EN50284 (resistance less than 1 GΩ) and make sure that it can not come
loose in any operation situation.

WARNING

VAISALA_______________________________________________________________________ 19

During the installation work of the probes in gas group IIC areas
(requiring category I devices), it has to be guaranteed that even in fault
cases sparks generated by impacts or friction on the surface of the housing
can never occur.

User’s Guide______________________________________________________________________

Selecting Location

Select a place with stable conditions for mounting the transmitter. Do not
expose the transmitter to direct sunlight or rain. A rain shield is available
and it is recommended for direct outdoor installations. When mounting the
probe, select a place representing the process conditions.

General Instructions for Probes with Cable

Mount the probes with a cable horizontally; this way, any water
condensing on the tube cannot flow onto the sensor.

0507-024

Figure 3 Horizontal Mounting of Probe

The following numbers refer to Figure 3 on page 20:
1 = To be sealed
2 = To be insulated
3 = Insulate the cable
4 = Let the cable hang loosely. This prevents condensed water

running to the sensor along the cable.

When there is no alternative but to install the probe in the process
vertically, the point of entry must be carefully insulated. The cable must
also be allowed to hang loosely as this prevents any condensed water from
running onto the probe along the cable.

20 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

0507-022

Figure 4 Vertical Mounting of Probe

The following numbers refer to Figure 4 on page 21:
1 = To be sealed
2 = Insulate the cable
3 = To be insulated
4 = Let the cable hang loosely. This prevents condensed water

running to the sensor along the cable

If the process temperature is much higher than that of the environment, the
whole probe and preferably plenty of cable must be inside the process. This
prevents measuring inaccuracy caused by heat conduction along the cable.

When mounted on the side of a duct or channel, the probe must be inserted
from the side of the duct. If this is not possible and the probe must be
inserted from the top, the point of entry must be carefully insulated.

For Vaisala probe installation kits and some installation examples see
section Probe Mounting on page 24.

VAISALA_______________________________________________________________________ 21

User’s Guide______________________________________________________________________

Checking the Temperature Reading

The actual temperature of the process can be measured with a reference
instrument to be compared with the transmitter reading. The heat transfer
is less evident if you remove the protective filter of the sensor for a short­term test. However, never use the sensor long periods without the filter as
this may cause a faster contamination of the sensor. The transmitter fulfils
the specified EMC regulations with the protective filter on the probe.

In humidity measurement and especially in calibration and adjustment it is
essential that temperature of the probe and measuring environment is the
same. Even a small difference in temperature between the environment and
the probe causes an error. As the curve below shows, if the temperature is
+20 °C and the relative humidity 100 %RH, a difference of ±1 °C between
the environment and the probe causes an error of ±6 %RH.

The graph below illustrates the measurement error at 100 %RH when the
difference between the ambient and sensor temperature is 1 °C.

0507-036

Figure 5 Measurement Error at 100 %RH

22 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

Mounting the Transmitter Housing

1. Attach the mounting plate to the wall with 4 screws.

2. Press down the transmitter so that it slides along the rails of the

mounting plate.

3. Fasten the transmitter to the mounting plate with the Allen screw

(3 mm Allen key provided).

The probe can be detached and replaced when needed by simply
unfastening the two Allen screws.

0603-037

Figure 6 Transmitter Mounting

The following numbers refer to Figure 6 on page 23:

1 = Mounting plate
2 = Transmitter housing
3 = Allen screw
4 = Allen screws

VAISALA_______________________________________________________________________ 23

User’s Guide______________________________________________________________________

0603-038

Figure 7 Parts of the Transmitter

The following numbers refer to Figure 7 on page 24:
1 = Electronics unit
2 = Probe; including a part of the measurement electronics (for

example, calibration memory)
3 = Flat cable
4 = Transmitter base
5 = Grounding terminal
6 = Protective covers
7 = Cable glands
8 = Probe
9 = RS232C connector

Probe Mounting

CAUTION

Do not unsolder and then resolder the probe cable from and to the printed
board during installation.

Do not shorten or lengthen the probe cable.
These procedures may alter the humidity calibration of the transmitter.

24 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

HMP363 for Confined Spaces

The HMP363 is a small size (ø = 12mm) general-purpose probe suitable
for ducts and channels with the installation kit available from Vaisala.

The HMP363 provides for two measuring range options. The first probe
version is equipped with a flexible cable and can be used when measuring
in environments up to 80 ºC. The second version is suitable for measuring
in environments up to 120 ºC.

Section HMP363/365/367 Duct Installation Kit on page 25 shows
mounting of HMP363/367 with the optional duct installation kit.

HMP363/365/367 Duct Installation Kit

0508-021

Figure 8 Installation of HMP363 Probe in Duct with Flange and

Supporting Bar

The following numbers refer to Figure 8 on page 25:
1=Duct wall
2 = Flange
3 = Sealing ring
4 = Supporting bar
5 = Probe attaching part (to be fixed with supporting bar)
6 = RH probe

VAISALA_______________________________________________________________________ 25

User’s Guide______________________________________________________________________

HMP364 for High-Pressure Applications

The probe is provided with a nut, a fitting screw and a sealing washer.
Keep the fitting screw and the nut in place on the body of the probe during
handling to prevent damage to the highly polished surface of the probe.
Follow the instructions below to achieve a leak-tight assembly.

CAUTION

NOTE

In pressurized processes it is essential to tighten the supporting nuts and
screws very carefully to prevent loosening of the probe by the action of
pressure.

1. Remove the fitting screw from the nut and the probe.

2. Fasten the fitting screw to the chamber wall with a sealing washer.

Tighten the fitting screw into the threaded sleeve with a torque
spanner. The tightening torque is 150 ± 10 Nm (110 ± 7 ft-lbs).

3. Insert the body of the probe into the fitting screw and tighten the nut

manually to the fitting screw.

4. Mark both the fitting screw and the nut hex.

5. Tighten the nut a further 30º (1/12) turn or if you have a torque

spanner tighten it with a torque of 80 ± 10 Nm (60 ± 7 ft-lbs).

6. Clean and grease the tightening cone of the fitting screw after every

tenth detachment. Change the sealing washer every time the fitting
screw is detached. Use high-vacuum grease, for example Dow
Corning, or a similar grease.

When retightening the nut after detachment the nut must be tightened
without increased effort.

26 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

0505-272

Figure 9 HMP364 Probe Mounting

The following numbers refer to Figure 9 on page 27:
1 = Tightening cone
2=Nut
3 = Fitting screw, M22×1.5 or NPT 1/2"
4 = Sealing washer
5 = Probe; ø12 mm

0505-273

Figure 10 Marking Nut and Fitting Screw

VAISALA_______________________________________________________________________ 27

User’s Guide______________________________________________________________________

0505-274

Figure 11 Cleaning the Tightening Cone

The following numbers refer to Figure 11 on page 28:
1 = Fitting screw
2 = Sealing washer

CAUTION

NOTE

3 = Tightening cone
4 = Clean cotton stick

In pressurized processes it is essential to tighten the supporting nuts and
screws very carefully to prevent loosening of the probe by the action of
pressure.

When HMP364 is installed in a process with a pressure differing from
normal atmospheric pressure, please enter the pressure value of the
process (in bar

) into the transmitter memory, see sections PRES Setting

a

Ambient Pressure for Calculations on page 55 and Setting the Pressure for
Calculations on page 46.

28 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

HMP365 for High Temperatures

HMP365 is installed similarly to the HMP363 probe but without the
supporting bar. Refer to HMP363/365/367 Duct Installation Kit on page 25
for more information on the duct installation kit for HMP365.

To avoid incorrect humidity readings, there must not be significant
temperature differences between the inside and outside of the duct.

0505-271

Figure 12 Mounting HMP365 Probe in Duct or Channel

The following numbers refer to Figure 12 on page 29:
1 = A plugged hole for reference measurements
2 = Probe
3 = Mounting flange

HMP367 for High Humidities

The HMP367 is for environment where relative humidity is very high, near
saturation.

Section HMP363/365/367 Duct Installation Kit on page 25 shows
mounting of HMP363/367 with the optional duct installation kit.

VAISALA_______________________________________________________________________ 29

User’s Guide______________________________________________________________________

HMP368 for Pressurized Pipelines or Moisture in Liquids

Due to the sliding fit the HMP368 is easy to install into and remove from
a pressurized process. The probe is especially suitable for measurements
inside pipelines. See section Installing the HMP368 Probe Through a Ball

Valve Assembly on page 32.

CAUTION

NOTE

In pressurized processes it is essential to tighten the supporting nuts and
screws very carefully to prevent loosening of the probe by the action of
pressure.

When HMP368 is installed in a process with a pressure differing from
normal atmospheric pressure, please enter the pressure value of the
process (in bara) into the transmitter memory. See sections PRES Setting

Ambient Pressure for Calculations on page 55 and Setting the Pressure for
Calculations on page 46.

0603-013

Figure 13 HMP368 Probe

The following numbers refer to Figure 13 on page 30:
1 = Clasp nut, 24 mm hex nut
2 = Fitting body, 27 mm hex nut

30 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

The following two fitting body options are available:

- Fitting Body ISO1/2 solid structure

- Fitting Body NPT1/2 solid structure

Table 4 HMP368 Probe Dimensions

Probe Type Probe Length Adjustment Range

Standard 178 mm 120 mm
Optional 400 mm 340 mm

CAUTION

Take care not to damage the probe body. A damaged body makes the
probe head less tight and may prevent it from going through the clasp nut.

0507-025

Figure 14 Sealing of Fitting Body into Process

Tightening the Clasp Nut

1. Adjust the probe to a suitable depth according to the type of
installation.

2. Tighten the clasp nut first manually.

3. Mark the fitting screw and the clasp nut.

4. Tighten the nut a further 50 ... 60° (ca. 1/6 turn) with a fork spanner.
If you have a suitable torque spanner, tighten the nut to 45 ± 5 Nm (33
± 4 ft-lbs).

VAISALA_______________________________________________________________________ 31

User’s Guide______________________________________________________________________

0505-276

Figure 15 Tightening the Clasp Nut

NOTE

The following numbers refer to Figure 15 on page 32:
1 = Probe
2 = Clasp nut
3 = Fitting screw
4=Pen

Take care not to tighten the clasp nut more than 60° to avoid difficulties
when opening it.

Installing the HMP368 Probe Through a Ball Valve Assembly

The ball valve installation kit (Vaisala order code: BALLVALVE-1) is
preferred when connecting the probe to a pressurized process or pipeline.
Use the ball valve set or a 1/2" ball valve assembly with a ball hole of ø14
mm or more. If you install the probe (ø12 mm) in a process pipe, please
note that the nominal size of the pipe must be at least 1 inch (2.54 cm). Use
the manual press handle to press the probe into the pressurized (< 10 bar)
process or pipeline.

32 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

0505-277

Figure 16 Installing the HMP368 Probe Through a Ball Valve

Assembly

NOTE

NOTE

The numbers below refer to Figure 16 on page 33:
1 = Manual press tool
2 = Handle of the ball valve
3 = Probe
4 = Process chamber/pipeline
5 = Groove on the probe indicating the upper adjustment limit
6 = Filter
7 = Ball of the ball valve

The probe can be installed in the process through the ball valve assembly
provided that the process pressure is less than 10 bar. This way, the
process does not have to be shut down when installing or removing the
probe. However, if the process is shut down before removing the probe,
the process pressure can be max. 20 bar.

When measuring temperature dependent quantities make sure that the
temperature at the measurement point is equal to that of the process,
otherwise the moisture reading may be incorrect.

VAISALA_______________________________________________________________________ 33

User’s Guide______________________________________________________________________

Follow the steps below to install the HMP368 probe through a ball valve
assembly. After the installation, the probe should be sitting in the process
chamber or pipeline as shown in Figure 16 on page 33.

1. Shut down the process if the process pressure is more than 10 bars. If
the pressure is lower there is no need to shut down the process.

2. Close the ball valve.

3. Seal the threads on the fitting body; refer to Figure 14 on page 31.

4. Attach the fitting body to the ball valve and tighten it.

5. Slide the clasp nut of the probe toward the filter, as far as it will go.

6. Insert the probe to the fitting body, and manually tighten the clasp nut
to the fitting body.

7. Open the ball valve.

8. Push the probe through the ball valve assembly into the process. If the
pressure is high, use the pressing handle that is provided with the
probe. If you push the probe hard without using the handle, you may
damage the cable.

NOTE

Note that the probe must be pushed so deep that the filter is
completely inside the process flow.

9. Mark the fitting screw and the clasp nut.

10. Tighten the clasp nut with a fork spanner a further 50 ... 60º (ca. 1/6
turn). If you have a suitable torque spanner, tighten the nut to max 45
± 5 Nm (33 ± 4 ft-lbs). Refer to Figure 15 on page 32.

Take care not to tighten the clasp nut more than 60° to avoid difficulties
when opening it.

If you wish to remove the probe from the process, note that you have to pull
the probe out far enough. You cannot close the valve if the groove on the
probe body is not visible.

34 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

Electrical Connections

Refer to local requirements regarding cabling, grounding and galvanic
isolator or barrier connections.

WARNING

WARNING

NOTE

Connect the transmitter always via galvanic isolators or Zener barriers in
hazardous environments.

Be sure that the main power switch of the transmitter is set off before
making any electrical installations in hazardous areas.

1. Open the transmitter cover and remove the protective cover of the
transmitter base.

2. Thread the power supply wires through the cable gland, see Figure 7

on page 24.

3. Connect the unpowered power supply wires to the connectors: Ch 1
(humidity) and Ch 2 (temperature). Both channels require an own
power supply.

4. Replace the protective cover. Turn the transmitter on ON with the
ON/OFF switch, see Figure 24 on page 60.

5. Close the cover. The transmitter is ready for use.

As Ch 1 is a main output, the transmitter does not operate if only Ch 2 is
connected (Ch 2 is optoisolated from transmitter electronics).

When using the transmitter in hazardous locations, the use of galvanic
isolators or barriers is essential. The following barrier & isolator are
available in Vaisala: barrier No. 210664 (STAHL 9001/51-280-091-141)
and galvanic isolator No. 212483 (STAHL 9160/13-11-11). Examples of
connections and more information on installation in hazardous locations is
given in section Examples of Connections on page 41.

VAISALA_______________________________________________________________________ 35

User’s Guide______________________________________________________________________

Installation in Hazardous Locations

US and Canadian Requirements

USA (FM): Wiring for intrinsically safe operation is shown in Appendix

B, Wiring for Intrinsically Safe Operation, FM, on page 89.

Canada (CSA): Wiring for intrinsically safe operation is shown in

Appendix C, Wiring for Intrinsically Safe Operation, CSA, on page 91.

European Requirements

CATEGORY 1 (Zone 0)

HMT360 has to be connected to Exia-certified associated apparatus with
galvanic isolation, gas group IIB or IIC.

NOTE

NOTE

If both analog outputs are in use, the Ch 1 (-) and Ch 2 (-) must be short
circuited (see Figure 19 on page 41).

CATEGORY 2 or 3 (Zone 1 or 2)

HMT360 has to be connected either to a Zener barrier or galvanic isolator

If both analog outputs are in use with a galvanic isolator, the Ch 1 (-) and
Ch 2 (-) must be short circuited (see Figure 19 on page 41).

Figure 17 on page 39 and Figure 18 on page 40 present examples of

galvanic isolators and Zener barrier connections (only Ch 1 connected).

36 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

Maximum Cable Resistance Calculation for the Barrier (Vaisala Order Code: 210664)

General specifications of HMT360:

Supply voltage Uin = 24 V (12 ... 35 V)
Maximum current I
Minimum operating voltage for

= 20 mA

out

U

= 12 V (15 V with serial port)

min

HMT360

Stahl 9001/51-280-091-141 (values taken from the specifications):

Rated operating voltage UN = 20 ... 35 V
Transmitter supply voltage US = UN - 9.5 V, when

UN≤ 23.5 V
or US = 14 V, when UN≥ 23.5 V

Maximum load RL≤ 350 Ω

VAISALA_______________________________________________________________________ 37

User’s Guide______________________________________________________________________

Calculation of the maximum cable length from barrier to transmitter:

Cable resistance (as an example) R

= 0.085 Ω/m/core (2 ×

cable

0.085 Ω/m/pair)

If assuming that the operating voltage would be ≥ 24 V, the maximum
acceptable voltage drop U

U

= US - U

drop

U

= 14 V - 12 V = 2 V

drop

min

in cables is:

drop

We also know that:
I

= 20 mA

out

and that total resistance of the cable R

cabletot

multiplied with the total maximum length of the cables l

R

cabletot

= R

cable

× l

max

is cable resistance R

:

max

cable

From these facts the following equation can be formed:

NOTE

U

= R

drop

2 = 2 × 0.085 Ω/m × l

l

= 2 V / (20 mA × 2 × 0.085 Ω/m)

max

= 588 m = 1930 ft, maximum cable length.

l

max

cabletot

× I

out

× 20 mA

max

If longer cable length is required, use of the galvanic isolators is
recommended if possible.

38 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

HAZARDOUS AREA SAFE AREA

a) current signal controller

I

HAZARDOUS AREA SAFE AREA

b) voltage signal controller

HMT360 Connected to a Galvanic Isolator

0505-278

0505-279

Figure 17 HMT360 Connected to Galvanic Isolator

VAISALA_______________________________________________________________________ 39

User’s Guide______________________________________________________________________

a) current signal controller

HAZARDOUS AREA SAFE AREA

HMT360 Connected to a Zener Barrier

0505-280

0505-281

Figure 18 HMT360 Connected to a Zener Barrier

40 ___________________________________________________________________ M010056EN-I

Chapter 3 _______________________________________________________________ Installation

Examples of Connections

0505-282

Figure 19 STAHL 9160/13-11-11 (Galvanic Isolator)

0505-283

Figure 20 STAHL 9001/51-280-091-141 (Zener Barrier)

VAISALA_______________________________________________________________________ 41

User’s Guide______________________________________________________________________

HAZARDOUS AREA SAFE AREA

Grounding

When grounding the transmitter, follow the local requirements. Use at least
4 mm2 grounding cable when grounding the transmitter or barrier. Note

that the allowed resistance between barrier and system ground must be less
than 1 ohm. Use ground terminal located inside or outside of transmitter

Figure 21 on page 42:

0505-284

Figure 21 Grounding

42 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

CHAPTER 4

OPERATION

This chapter contains information that is needed to operate this product.

Local Interface

HMT360 transmitter has four pushbuttons located on the housing cover.
The transmitter can be ordered either with or without a local display. The
display/keypad commands (see Display/Keypad Commands on page 46)
can be used to scale the outputs and select special output quantities (if the
transmitter configuration includes special output quantities). The optional
display shows the measurement results.

The keypad pushbuttons are indicated (from left to right) as C, Up, Dn, and
E (see Figure 22 on page 43):

0603-039

Figure 22 Local Display/Keypad Interface

VAISALA_______________________________________________________________________ 43

User’s Guide______________________________________________________________________

Power ON/OFF

Open the transmitter cover and flip the internal power switch to position
ON (up), see Figure 24 on page 60.

WARNING

WARNING

Avoid static discharge. Always use a wet cloth for wiping the display.

HMT360 with Display

Measurement readings appear on the display after switching power ON.
The analog output signals can be read from the system or load resistor.

Avoid static discharge. Always use a wet cloth for wiping the display.

HMT360 without Display

If the transmitter does not have a display, the red LED indicator on the
cover indicates various phases of calibration and possible errors. In normal
operation it is not lit. If the LED is lit and all calibration or test DIP
switches are disabled, it is an indication of an internal error.

Otherwise, the LED indicates the following:

NOTE

- LED blinking = calibration of the dry end (offset).

- LED lit = calibration of the wet end (gain).

If calibration is concluded but DIP switch settings are not restored, the
LED indicator keeps blinking.

44 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

DIP Switch Functions

The table below is also printed on the protection board:

NOTE

0505-285

Figure 23 DIP Switch Functions
1: Analog output test on/off

If you turn the switch to on position (up), you can force the outputs to states
4 mA, 12 mA and 20 mA by pressing buttons Up and Dn on the cover.
Outputs return to normal mode when switch is turned down.

2: Calibration Disabled/Enabled

The EEPROMs are write protected. If this switch is in the disabled position
(down), it does not allow any calibrations or scalings.

Keep this switch always in the disabled position during normal use of the
transmitter.

3 and 4: Calibration rh, t, analog

With these combinations you can perform relative humidity, temperature
or analog output calibrations with a multimeter or with the transmitter
display unit. Turn the DIP switches to the desired position according to the
table printed on the protective cover.

5: Output quantities

Determines whether the output units are metric (down) on non-metric.

6, 7 and 8: Select output quantities

VAISALA_______________________________________________________________________ 45

User’s Guide______________________________________________________________________

With the three DIP switches on the right, you can select the output
quantities according to the table printed on the right side of the protective
cover. Note that only the ordered quantities can be selected. The special
option gives you the choice of setting any ordered quantity to each channel.

NOTE

NOTE

Always restore the DIP switch settings after having tested the analog
outputs or performing the calibration.

Display/Keypad Commands

Chapter 6, Calibration and Adjustment, on page 59 describes separately

display/keypad commands for calibration and adjustment.

Setting the Pressure for Calculations

In humidity transmitters, ambient pressure is used for the mixing ratio and
wet bulb calculations.

To modify the pressure settings, turn the internal Calibration Enabled/
Disabled DIP switch of the transmitter to position Enabled (up). Press
button C on the display cover: text "SCAL" appears on the display. Then
press button E until the following display appears (the numeric value is
always the existing setting, in this example 1.0):

0505-087

Adjust the pressure reading with buttons Up and Dn. Acknowledge the
value with button E. To complete the pressure setting, turn the dip switch
back to position disabled (down).

See the pressure conversion table on page Table 6 on page 55.

Selecting Output Quantities

Upper Half of Display

To modify the displayed quantity, turn the Calibration Enabled/Disabled
DIP switch of the transmitter to position Enabled (up). Select the required

46 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

quantity with button Up on the display cover, and acknowledge the value
with button E. To complete the selections, turn the DIP switch back to
position disabled (down).

Character Quantity Abbreviation Availability Metric Unit Nonmetric Unit

0 relative humidity RH A, D %RH %RH
1 temperature T A, D, F, H °C °F
2 dewpoint

temperature

3 absolute humidity a D
4 mixing ratio x D g/kg gr/lb

5 wet bulb

temperature

6mass

concentration of

water
7 water activity aw H, F 0 ... 1 0 ... 1
8 relative humidity

of saturation
9 saturation

temperature

Td D °C °F

3

g/m

Tw D °C °F

ppmw H ppm

RS H %RS %RS

Ts H °C °F

w

gr/ft

ppm

3

w

The characters used to indicate availability in the table above:
A = Available for HMT360 standard version
D = Available for HMT360 with optional calculations
F = Available for HMT360 Moisture and Temperature in oil

transmitter

H = Available for HMT360 Moisture and Temperature in Jet Fuel

transmitter

Lower Half of Display

The output quantities metric/non metric DIP switch can be used to select
between °C and °F.

It is possible to check the pressure setting of the transmitter by pressing
button Dn. To return to the temperature reading, press button Dn again.

VAISALA_______________________________________________________________________ 47

User’s Guide______________________________________________________________________

Selecting Analog Outputs

You can select the output quantities for channels 1 and 2 by turning the

Calibration Enabled/Disabled DIP switch of the transmitter to position
Enabled (up) and the three output selection DIP switches to position

special (all up).
Press button C on the display cover: text "SCAL" appears on the display.

Then press button E until the following display appears:

0505-288

The characters on the second line of the display in this menu correspond to
the quantities according to the table in section Selecting Output Quantities

on page 46.

NOTE

Select the quantity for Ch 1 with buttons Up and Dn and acknowledge the
selection with button E.

If the transmitter is equipped with two analog channels, select the quantity
for Ch 2 in the same way, for example:

0505-289

Press button C to exit the display command mode or continue by setting
the pressure.

Remember to restore the DIP switch settings.

Scaling Analog Outputs

Turn the internal Calibration Enabled/Disabled DIP switch of the
transmitter to upward position (on). Press button C on the display cover
and a text similar to the following appears:

48 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

0505-290

Numbers on the second line indicate the low end scaling of Ch 1 currently
stored in the transmitter memory. The text "Set Lo" on the lower left corner
indicates that you can now change the low end scaling with buttons Up and
Dn. Acknowledge the value with button E and a text similar to the
following appears:

NOTE

0505-291

Numbers on the second line indicate the high end scaling of Ch 1. The text
"Set Hi" on the lower left-hand corner indicates that you can now change
the high end scaling with buttons Up and Dn. Acknowledge with button E.

If there is another channel available, the display shifts to the scaling menu
of Ch 2. You can now scale the analog outputs for the Ch 2 in the same way
as described above.

Press button C to exit the display command mode or continue by selecting
the output quantities. This menu starts automatically after the scaling menu
only if the output selection DIP switches are on the position special (all up)
from the beginning.

Remember to restore the DIP switch settings.

VAISALA_______________________________________________________________________ 49

User’s Guide______________________________________________________________________

Serial Interface

WARNING

NOTE

NOTE

The serial interface MUST NOT be used in hazardous areas.

Use the serial interface for calibration and testing purposes in safe areas
only. Always use the serial interface cable (optional accessory, Vaisala
order code: 25905ZZ). Connect one end of the cable to the serial port of
your computer and the other to the connector marked "RS232C" on the
electronics unit of the transmitter (see Figure 7 on page 24).

With serial communication the current consumption increases
approximately to 7 mA and the transmitter is not able to operate with
4 mA. Therefore, it is recommended to use serial communication only
temporarily for changing settings or for calibrating the transmitter in a
safe area. With serial port, the minimum supply voltage is 15 VDC.

The transmitter incorporates a serial interface detector. However, not all
terminals or PC serial ports (for example, optoisolated or ports not
meeting RS232C standards) recognize this standard. If the
communication is not possible via a serial interface, use a forced
activation by pressing simultaneously buttons Up and E on the
transmitter cover. To deactivate the forced activation, press these buttons
again or reset the transmitter. If the transmitter does not receive any
commands for half an hour, it automatically closes the serial
communication.

Serial Communication Settings

Table 5 Serial Communications Settings

Parameter Value

bauds 2400
parity none
data bits 8
stop bits 1

CAUTION

50 ___________________________________________________________________ M010056EN-I

When using the serial interface, be sure that power supply and serial
interface are not connected to the same ground (use a floating power
supply or hand-held serial interface device).

Chapter 4 ________________________________________________________________ Operation

To start issuing commands, make sure that HMT360 is connected to a
serial port of your computer and that the terminal session is open. Issue
commands by typing them on your computer according to the following
instructions. In these commands, <cr> stands for pressing Enter (on your
computer keyboard).

Setting the Analog Outputs

ASEL Selecting Analog Outputs

Syntax: ASEL [xxxyyy]<cr>

where
xxx = Quantity of Ch 1
yyy = Quantity of Ch 2

Turn the internal DIP switch Calibration Enabled/Disabled to position
ON before the selecting the analog outputs and return it to position OFF
after making the selection. Output quantities and their abbreviations are
listed in the table below:

Character Quantity Abbreviation Availability Metric Unit Nonmetric Unit

0 relative humidity RH A, D %RH %RH
1 temperature T A, D, F, H °C °F
2 dewpoint

temperature
3 absolute humidity a D

4 mixing ratio x D g/kg gr/lb
5 wet bulb

temperature
6mass

concentration of

water
7 water activity aw H, F 0 ... 1 0 ... 1
8 relative humidity

of saturation
9 saturation

temperature

Td D °C °F

3

g/m

Tw D °C °F

ppmw H ppm

RS H %RS %RS

Ts H °C °F

w

gr/ft

ppm

3

w

VAISALA_______________________________________________________________________ 51

User’s Guide______________________________________________________________________

Example:

>asel rh t
Ch1 RH lo : 0.00 %RH
Ch1 RH hi : 100.00 %RH
Ch2 T lo: -40.00 ’C
Ch2 T hi: 100.00 ’C
>

S Scaling Analog Outputs

Syntax: S [zz aa.a bb.b]<cr>

where
zz = Quantity (RH, T, Td, x, a, Tw, ppm, aw, RS, Ts)
aa.a = Lower limit of the quantity
bb.b = Upper limit of the quantity

NOTE

Turn the internal DIP switch Calibration Enabled/Disabled to position
ON before the scaling the analog outputs and return it to position OFF

after scaling.

Example:

>srh 0 100
RH lo: 0.00 %RH
RH hi: 100.00 %RH
>

Adjustment Commands

Turn the internal DIP switch Calibration Enabled/Disabled to position
ON before the adjustment and return it to position OFF after the

adjustment.

CRH Relative Humidity Adjustment

Read also the calibrator, for example HMK15, manual and refer to page
19 of that manual for more detailed instructions on salt bath calibration
and adjustment.

Syntax: CRH<cr>

52 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

The transmitter asks and measures relative humidity and calculates the
calibration coefficients.

Example:

>crh
RH : 1.82 1. ref ? 0
Press any key when ready ...
RH : 74.222 2. ref ? 75
OK
>

The OK indicates that the adjustment was succesful.

CT Temperature Adjustment

Syntax: CT<cr>
The transmitter asks and measures temperature readings and calculates the

calibration coefficients.

NOTE

Example:

>ct
T : 0.811 1. ref ? 0.5
Press any key when ready ...
T : 99.122 2. ref ? 99.5
OK
>

The OK indicates that the adjustment was succesful. When performing
one-point adjustment press only Enter for the second reference.

Output Commands

ITEST Testing Analog Outputs

Before giving command ITEST, reset the transmitter with command
RESET, see section RESET Transmitter Reset on page 56.

Syntax: ITEST [aa.aaa bb.bbb]<cr>

where
aa.aaa = Current value to be set for Ch 1 (mA)
bb.bbb = Current value to be set for Ch 2 (mA)

VAISALA_______________________________________________________________________ 53

User’s Guide______________________________________________________________________

This command outputs the current value of each channel and the
corresponding control signal of the digital-to-analog converter.

Example:

>itest 8 12

8.00000 403 12.00000 7DF
>itest

7.00150 30A 11.35429 73E
>

The set current values remain valid until you issue the command ITEST
without readings or reset the transmitter. With this command the desired
outputs of the transmitter are shown.

NOTE

When outputting low currents from Ch 1, remember to remove RS232C­cable while reading the current output, because of the increased current
consumption for using RS port.

SEND Outputting Measurement Values

Syntax: SEND<cr>
This command outputs the measured values in one point.

R Activating Continuous Output

Syntax: R<cr>
With the command R the transmitter outputs measured values

continuously.

S Stopping Continuous Output

Syntax: S<cr>
The continuous outputting is stopped with the command S. If outputting is

active, this command is not echoed.

INTV Setting Output Interval

Syntax: INTV [n xxx]<cr>

where

54 ___________________________________________________________________ M010056EN-I

Chapter 4 ________________________________________________________________ Operation

n = 1 ... 255
xxx = S, MIN or H

Sets the output interval when the transmitter outputs measurement
readings. The time interval is used when the continuous output is active.

Example, the output interval is set to 10 minutes:

>intv 10 min
Output interval: 10 MIN
>

PRES Setting Ambient Pressure for Calculations

Syntax: PRES [aaaa.a]<cr>

where
aaaa.a = Pressure (bara)

Turn the internal DIP switch Calibration Enabled/Disabled to position
ON before setting the pressure and return it to position OFF after making
the setting.

Example:

>pres 12
Pressure : 12.0 bara
>

Table 6 Pressure Conversion Chart

FROM hPa/mbar mmHg/Torr inHg atm bar psi

hPa/
mbar

TO mmHg/

Torr
inHg 0.02952999 0.03937008 1 29.921 29.52999 2.036021
atm 0.00098692 0.00131597 0.033422 1 0.98692 0.068046
bar 0.001 0.001333224 0.03386388 1.01325 1 0.06894757
psi 0.01450377 0.01933678 0.4911541 14.6962 14.50377 1

1 1.333224 33.86388 1013.25 1000 68.94757

0.7500617 1 25.40000 760 750.0617 51.71493

Example:

29.9213 inHg = 29.9213 × 33.86388 = 1013.25 hPa / mbar

VAISALA_______________________________________________________________________ 55

User’s Guide______________________________________________________________________

NOTE

Conversions from mmHg and inHg are defined at 0 °C.

FILT Output Filtering

Syntax: FILT [a.aaa]<cr>

where
a.aaa = 0.1 ... 1

1=No filtering

0.5 = Average of last two measurements

0.1 = Average of ca. 16 measurements

This commands sets the measurement result filtering.

Example:

>filt 1
Filter : 1.0000
>filt 0.5
Filter : 0.5000
>filt 0.1
Filter : 0.1000
>

Resetting the Transmitter

RESET Transmitter Reset

Syntax: RESET<cr>
This command resets the device.

56 ___________________________________________________________________ M010056EN-I

Chapter 5 __________________________________________________ Measuring at Overpressure

CHAPTER 5

MEASURING AT OVERPRESSURE

This chapter provides you with important information concerning
measurement in conditions with pressure higher than the normal
atmospheric pressure.

The probes HMP364 and HMP368 are designed for humidity
measurement at overpressure. The maximum measurement pressures
depend on the probe as follows:

HMP364: 0 ... 100 bar (10 MPa), for pressurized rooms and

processes, probe is provided with a nut, fitting screw
and sealing washer

HMP368: 0 ... 40 bar (4 MPa), for pressurized pipelines, ball

valve set available

The accuracy of the dewpoint measurement is affected by pressure in the
measurement chamber. The actual pressure in the sampling cell is required
to be set to the transmitter by using the serial line command PRES (see
section PRES Setting Ambient Pressure for Calculations on page 55 or by
using the keypad commands, see section Setting the Pressure for

Calculations on page 46).

Pressure Regulator Recommended

When sampling pressurized processes exceeding the maximum
measurement pressure of the probe, the pressure in the measurement
chamber must be regulated to the acceptable level or below. It is
recommended to use pressure regulator before the measurement chamber
to prevent remarkable pressure variations.

VAISALA_______________________________________________________________________ 57

User’s Guide______________________________________________________________________

58 ___________________________________________________________________ M010056EN-I

Chapter 6 __________________________________________________ Calibration and Adjustment

CHAPTER 6

CALIBRATION AND ADJUSTMENT

This chapter contains instructions for checking the calibration and
adjusting this product.

In this User's Guide the term "calibration" refers to comparing the device 's
reading against a reference concentration. "Adjustment" refers to changing
the device's reading to correspond to the reference concentration.

Calibration Interval

HMT360 is calibrated as shipped from the factory. Typical calibration
interval is one year. In demanding applications it may be advisable to make
the first calibration check earlier.

Factory Calibration and Adjustment

The device (or the probe only) can be sent to Vaisala Service Centers for
calibration and adjustment. See section Technical Support on page 72 for
contact information.

User Calibration and Adjustment

Calibration and adjustment is carried out by using the keypad or by using
serial commands. The following additional equipment is needed in
adjustment of HMT360:

- a power supply for the channel(s) to be calibrated (12 ... 24 VDC),

- a multimeter for HMT360 without a display, and

- the calibrated references.

VAISALA_______________________________________________________________________ 59

User’s Guide______________________________________________________________________

First, the electronics unit is removed from the transmitter base to perform
the calibration and adjustment in safe area. Second, the power supply and
a multimeter is connected to the electronics unit according to the following
instructions.

Removing the Electronics Unit

0603-040

Figure 24 Detaching the Electronics Unit with Probe for

Calibration and Adjustment

1. Unfasten the screws and open the cover.

2. Switch the transmitter off with the ON/OFF switch.

3. Disconnect the flat cable by lifting it carefully, for example with a
screwdriver.

4. Remove the two screws holding the hinge support. Remove the hinge
support.

5. Turn the electronics unit slightly upwards to release it from the hinges.
Leave the transmitter base with the cable connections on place. When
putting the electronics unit back to place, attach the upper hinge first.
Remember to attach the hinge support.

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Chapter 6 __________________________________________________ Calibration and Adjustment

A1

B1

B2

A2

C1

C2

On

Off

Connections

WARNING

0505-293

Figure 25 Connecting Power Supply and Multimeter for

Calibration

1. Connect a power supply (12 ... 24 VDC, with a serial port the
minimum supply voltage is 15 VDC ) to the terminals B1 (-) and C1
(+) (Ch 1) with banana plugs, see Figure 25 on page 61.

2. Connect the multimeter in series with the supply, B1 (-) and A1 (+).

3. Follow the same procedure with Ch 2 using the terminals B2 (-) and
C2 (+). When calibrating both channels at the same time, use two
galvanically separated power supplies.

You can now calibrate or check the humidity and temperature or the analog
outputs according to the instructions given in this chapter.

If the current measurement is needed in a hazardous area, the multimeter
is connected to the terminals A1/A2 (+) and B1/B2 (-). Use only an
approved multimeter.

The power supply connectors (C1 and C2) MUST NOT be used in
hazardous areas. For calibration and adjustment in a hazardous area use
only an approved multimeter, which fulfills the safety factors printed on
the protective cover.

VAISALA_______________________________________________________________________ 61

User’s Guide______________________________________________________________________

I 4 mA 16 mA

Q

ref

Q

min

–

Q

max

Q

min

–

-----------------------------

⋅+=

I 4 mA 16 mA

11.3 %RH 0 %RH–
100 %RH 0 %RH–

-------------------------------------------------

⋅+ 5.808 mA==

I 4 mA 16 mA

22.3° C40° C–
120° C40° C–

--------------------------------------

⋅+ 10.230 mA==

Calculating Correspondence of Current Values and Output Quantities

When using HMT360 without a display, calibration and adjustment is
carried out by using a multimeter. Use the following equations to calculate
the current values corresponding to the reference output quantities.

0605-015

where
Q

Q
Q

= Reference value of the calibrated quantity

ref

= Reference value of the calibrated quantity

min

= Value corresponding to 20 mA

max

Example 1:
Relative humidity scaling 0 ... 100 %RH, reference 11.3 %RH:

0605-016

Example 2:

Temperature scaling -40 ... +120 °C, reference 22.3 °C:

62 ___________________________________________________________________ M010056EN-I

0605-017

Chapter 6 __________________________________________________ Calibration and Adjustment

Relative Humidity Adjustment

Automatic Two-Point Adjustment (Only HMT360 with Display)

The automatic adjustment procedure is a user friendly way to adjust the
HMT360 with salt solutions; you do not have to feed the reference values
to the HMT360. The transmitter displays the accurate value based on the
measured temperature and the Greenspan table stored into the transmitter
memory. The display chart of the adjustment procedure is presented in

Figure 26 on page 64.

1. Set the internal DIP switch Calibration Enabled/Disabled to
position ON and select RH calibration by using switches 3 and 4 (see
section DIP Switch Functions on page 45).

2. Remove the filter and insert the probe into a measurement hole of the
LiCl salt chamber in the humidity calibrator. Acknowledge by
pressing button E. Alternatively select the 0.1 (humidity in nitrogen)
with buttons Up and Dn. Acknowledge with button E.

NOTE

3. You must now wait for the measured reading to stabilize (10 ... 15
min). When the transmitter detects that the reading is stable, it
automatically stores the correction. When the text "Auto" is displayed
on the screen, continue with the next step.

4. Insert the probe into a measurement hole of the NaCl salt chamber in
the humidity calibrator. Acknowledge by pressing button E.
Alternatively you can select K2SO4 value with buttons Up and Dn.

5. You must again wait for the measured reading to stabilize (10 ... 15
min). When the transmitter detects that the reading is stable, it
automatically stores the correction. The text "Cal Pass" is displayed
after the adjustment is performed.

Remember to restore the DIP switch settings.

VAISALA_______________________________________________________________________ 63

User’s Guide______________________________________________________________________

RH

Set Lo

RH

Set Lo

RH

Set Lo

RH

Set Lo

RH

Set Lo

RH

Set Lo

RH

Set Lo

RH

Set Lo

Calibration enabled
RHcalibration on

Restore switches

Wait

Wait

0604-061

Figure 26 Display Chart of the Automatic Adjustment Procedure

64 ___________________________________________________________________ M010056EN-I

Chapter 6 __________________________________________________ Calibration and Adjustment

Manual Adjustment

This section contains separate manual adjustment procedures for
transmitters with and without display. You can perform the low-end
adjustment only (one-point adjustment), or adjust both low and high end of
the measurement (two-point adjustment).

NOTE

If you use serial commands, please refer to section Adjustment

Commands on page 52.

Low End Adjustment (HMT360 without Display)

1. Connect the power supply and multimeter as instructed in section

Connections on page 61.

2. Remove the filter and insert the probe into a measurement hole of the
reference chamber (for example LiCl: 11 %RH) in the humidity
calibrator.

3. Power up the transmitter.

4. Set the internal DIP switch Calibration Enabled/Disabled to
position ON and select RH calibration by using switches 3 and 4 (see
section DIP Switch Functions on page 45).

5. The LED indicator will start blinking. According to the calibrator
used, wait at least 10 ... 15 minutes for the sensor to stabilize; use a
multimeter to monitor the stabilization.

6. Press buttons Up and Dn to adjust the multimeter reading to
correspond the reference value (calculate the current value
corresponding to the reference humidity by using the equations
presented in Calculating Correspondence of Current Values and

Output Quantities on page 62). Press button E to conclude the

adjustment.

7. To continue with the high end (two-point) adjustment follow the
instructions in the next section.

If the low end adjustment is sufficient, press button E again to
conclude the calibration. Also restore the DIP switch settings; set the
calibration DIP switch to position disabled (down).

VAISALA_______________________________________________________________________ 65

User’s Guide______________________________________________________________________

High End Adjustment (HMT360 without Display)

1. After having made the low end adjustment, insert the probe into a
measurement hole of the NaCl (75 %RH) salt chamber in the
humidity calibrator. Please, note that the difference between the two
humidity references must be at least 30 %RH.

2. The LED indicator lights up. Wait at least 10 ... 15 minutes for the
sensor to stabilize; use a multimeter to monitor the stabilization.

3. Press buttons Up and Dn to adjust the multimeter reading. Calculate
the current value corresponding to the reference humidity by using the
equations presented in Calculating Correspondence of Current Values

and Output Quantities on page 62.

4. Conclude the adjustment with button E.

5. Restore the DIP switch settings. Set the calibration DIP switch to
position disabled (down).

Low End Adjustment (HMT360 with Display)

1. Connect the power supply as instructed in section Connections on

page 61. The measurement readings will be visible on the display

during calibration, but you can also connect a multimeter to check the
analog output readings.

2. Remove the filter and insert the probe into a measurement hole of the
dry end reference chamber (for example LiCl: 11 %RH) in the
humidity calibrator.

3. Power up the transmitter.

4. Set the internal DIP switch Calibration Enabled/Disabled to
position ON and select RH calibration by using switches 3 and 4 (see
section DIP Switch Functions on page 45).

5. Press button C to ignore the automatic adjustment procedure. The
humidity reading measured by the transmitter appears on the display
and on the lower left corner you can see the text "Set Lo".

6. According to the calibrator used, wait at least 10 ... 15 minutes for the
sensor to stabilize; use the transmitter display to monitor the
stabilization.

7. Press buttons Up and Dn to adjust the display reading. Press button E
to conclude the low end adjustment.

8. To continue with the high end (two-point) adjustment follow the
instructions in the next section.

If the low end adjustment is sufficient, press button E again to
conclude the calibration. Also restore the DIP switch settings; set the
calibration DIP switch to position disabled (down).

66 ___________________________________________________________________ M010056EN-I

Chapter 6 __________________________________________________ Calibration and Adjustment

High End Adjustment (HMT360 with Display)

1. After having made the low end adjustment, insert the probe into a
measurement hole of the NaCl (75 %RH) salt chamber in the
humidity calibrator. Please, note that the difference between the two
humidity references must be at least 30 %RH.

2. The readings measured by the transmitter appear on the display, as
well as the text "Set Hi" on the lower left hand corner.

3. Wait at least 10 ... 15 minutes for the sensor to stabilize; use the
transmitter display to monitor the stabilization.

4. Press buttons Up and Dn to adjust the display and conclude the
adjustment with button E.

5. Restore the DIP switch settings. Set the calibration DIP switch to
position disabled (down).

One-Point Temperature Adjustment

NOTE

NOTE

Always use a high quality standard for adjusting the temperature.

If you use serial commands, please refer to section Adjustment

Commands on page 52.

1. Set the internal DIP switch Calibration Enabled/Disabled to
position ON and select T calibration by using switches 3 and 4 (see
section DIP Switch Functions on page 45).

2. The temperature value measured by the transmitter appears on the
display as well as the text "Set Lo" on the lower left corner. If the
transmitter has no display, the LED indicator starts to blink.

3. Let the sensor stabilize; use a multimeter or the trans mitter display to
monitor the stabilization.

4. Press buttons Up and Dn to adjust the display or multimeter reading
to correspond to the reference value (when using a multimeter
calculate the current value corresponding to the reference humidity by
using the equations presented in Calculating Correspondence of

Current Values and Output Quantities on page 62).

5. Conclude the one-point adjustment by pressing button E twice.

VAISALA_______________________________________________________________________ 67

User’s Guide______________________________________________________________________

ACAL Analog Output Calibration

Syntax: ACAL<cr>
Connect HMT360 to a multimeter. Issue the ACAL command:

1. Disconnect the serial cable from the transmitter while reading the
multimeter value for the Ch 1 (I1).

2. Reconnect the serial cable. Type the multimeter reading and press
Enter.

3. Type the higher current multimeter reading and press Enter.

Example:

>acal
Ch1 I1 ( mA ) ? 4.846
Ch1 I2 ( mA ) ? 19.987
>

68 ___________________________________________________________________ M010056EN-I

Chapter 7 ______________________________________________________________ Maintenance

CHAPTER 7

MAINTENANCE

This chapter provides information that is needed in basic maintenance of
the product.

Periodical Checking and Cleaning

Transmitter Housing and Probe

WARNING

Avoid static discharge. Always use a wet cloth for wiping the display.

The electronics unit of the transmitter, as well as the probe, can be removed
and replaced in the field. See section Removing the Electronics Unit on

page 60 for detailed information.

All other maintenance must be performed by qualified Vaisala personnel.
If a transmitter is damaged, contact your nearest Vaisala Service Center.
See section Product Returns on page 72 for contact information.

VAISALA_______________________________________________________________________ 69

User’s Guide______________________________________________________________________

70 ___________________________________________________________________ M010056EN-I

Chapter 8 ___________________________________________________________ Troubleshooting

CHAPTER 8

TROUBLESHOOTING

This chapter describes common problems, their probable causes and
remedies, and contact information.

Diagnostics

Operation Errors

The following symptoms indicate an operation error of the HMT360:

- The analog output(s) current drops below 4 mA.

- Display shows the word "ERROR".

- The LED on the cover is lit and no calibration is going on (transmitters

In the case of error:

- Check that the sensor is connected properly.

- Check if there is condensed water in the probe. If yes, let the probe

In case of constant error, contact the Vaisala Helpdesk. See section

Technical Support on page 72 for contact information.

without display).

dry.

Analog Output Test

Analog outputs can be tested with dip switch 1, see DIP Switch Functions

on page 45 for details.

VAISALA_______________________________________________________________________ 71

User’s Guide______________________________________________________________________

Technical Support

For technical questions, contact the Vaisala technical support by e-mail at

[e-mail]. Provide at least the following supporting

information:

- Name and model of the product in question

- Serial number of the product

- Name and location of the installation site

- Name and contact information of a technically competent person who
can provide further information on the problem.

Product Returns

If the product must be returned for service, see

www.vaisala.com/services/return.html.

For contact information of Vaisala Service Centers, see

www.vaisala.com/services/servicecenters.html.

72 ___________________________________________________________________ M010056EN-I

Chapter 9 ____________________________________________________________ Technical Data

CHAPTER 9

TECHNICAL DATA

This chapter provides technical data of the product.

Performance

Relative Humidity

Table 7 Relative Humidity Specifications

Property Description / Value

Measurement range 0 ... 100 %RH
Accuracy (including non-linearity, hysteresis and repeatability)
with HUMICAP® 180

and HUMICAP® 180R
at +15 ... 25 °C

at -20...+40°C
at -40 ... +180 °C

with HUMICAP®180L2
at -10...+40°C

at -40 ... +180 °C
Factory calibration uncertainty

(+20 °C)

Response time (90 %) for
HUMICAP® 180 and HUMICAP®
180L2 at +20 °C in still air

Response time (90 %) for
HUMICAP® 180R at +20 °C
in 0.1 m/s air flow

for typical applications
for typical applications
±1 %RH (0 ... 90 %RH)
±1.7 %RH (90 ... 100 %RH)
±(1.0 + 0.008 × reading) %RH
±(1.5 + 0.015 × reading) %RH

for applications with demanding
chemical environment
±(1.0 + 0.01 × reading) %RH
±(1.5 + 0.02 × reading) %RH

±0.6 %RH (0 ... 40 % RH )
±1.0 %RH (40 ... 97 %RH)
(Defined as ±2 standard deviation
limits. Small variations possible, see
also calibration certificate.)

8 seconds with grid filter 20 seconds
with grid + steel netting 40 seconds
with sintered filter

17 seconds with grid filter
50 seconds with grid + steel netting
60 seconds with sintered filter

VAISALA_______________________________________________________________________ 73

User’s Guide______________________________________________________________________

Temperature (+ Operating Pressure Ranges)

Table 8 Temperature Specifications

Property Description / Value

HMP361 -40 ... +60 °C
HMP363 80 °C -40 ... +80 °C
HMP363 120 °C -40 ... +120 °C
HMP364 -70 ... +180 °C, 0 ... 10 MPa

(0 ... 100 bar)
HMP365 -70 ... +180 °C
HMP367 -70 ... +180 °C
HMP368 -70 ... +180 °C, 0 ... 4 MPa

(0 ... 40 bar)
Accuracy at +20 °C ± 0.2 °C
Accuracy over temperature range See graph below
Sensor Pt 1000 RTD 1/3 Class B

IEC 751

0507-021

Figure 27 Accuracy over Temperature Range

74 ___________________________________________________________________ M010056EN-I

Chapter 9 ____________________________________________________________ Technical Data

Water Activity in Jet Fuel Applications

Table 9 Water Activity in Jet Fuel Applications Specifications

Property Description / Value

Measurement range 0 ... 1 a

40 ... +356 °F)

Accuracy when calibrated against high
quality, certified humidity standards

± 0.01 (0 ... 0.9)
± 0.02 (0.9 ... 1.0)

salt solutions (ASTM E104-85)

± 0.02 (0 ... 0.9)
± 0.03 (0.9 ... 1.0)

Response time (90 %) at +20 °C in still oil
(stainless steel filter)

Humidity sensor
Calculated variables available mass concentration of water

Accuracy of the water content better than ± 15 % of the

10 min

Va isala HUMICA P

relative humidity of saturation
saturation temperature

reading

at -40 ... +180 °C (-

w

®

Calculated Variables (Typical Ranges)

With HMP361 Probe

Table 10 HMP361 Calculated Variables Specifications

Property Description / Value

Dewpoint temperature -40 ... +60 °C
Mixing ratio 0 ... 160 g/kg d.a.
Absolute humidity 0 ... 160 g/m³
Wet bulb temperature 0 ... +60 °C

With HMP363, HMP364, HMP365, HMP367 and HMP368 Probes

Table 11 HMP363, HMP364, HMP365, HMP367& HMP368

Probes Calculated Variables Specifications

Property Description / Value

Dewpoint temperature -40 ... +100 °C
Mixing ratio 0 ... 500 g/kg d.a.
Absolute humidity 0 ... 600 g/m³
Wet bulb temperature 0 ... +100 °C

VAISALA_______________________________________________________________________ 75

User’s Guide______________________________________________________________________

Outputs

Table 12 Output Specifications

Property Description / Value

Two ana log outputs (one standard, one
optional)

Typical accuracy of analog outputs at
+20 °C

Typical temperature dependence of analog
outputs

RS232C serial output for service use only

in safe area

two wire 4 ... 20 mA

± 0.05 %/°C full scale

± 0.005 %/°C full scale

connector type RJ45

WARNING

General

Output connections are made via safety barriers.

Table 13 General Specifications

Property Description / Value

Operating voltage
with serial port (service mode)

Connections screw terminals,

Cable bushings M20×1.5 (7.5 ... 12 mm)

Conduit fitting M20×1.5 / NPT 1/2"
Operating temperature range for electronics

with display
Storage temperature range

Housing material G-AlSi 10 Mg (DIN 1725)
Housing classification IP 66 (NEMA 4X)
Housing dimensions 164 × 115 × 62 mm
Housing weight 950 g
Probe material Stainless steel (AISI 316L)
Fully electromagnetically compatible

according to standards

12 ... 28 V

15 ... 28 V

2

0.33 ... 2.0 mm

(AWG 14-22)

M20×1.5 (10.5 ... 15 mm)

-40 ... +60 °C

-20 ... +60 °C

-40 ... +70 °C

EN 61326-1: Electrical

equipment for measurement,

control and laboratory use -

EMC requirements; Industrial

environment

wires

76 ___________________________________________________________________ M010056EN-I

Chapter 9 ____________________________________________________________ Technical Data

NOTE

IEC 1000-4-5 complies only when using external EXi approved surge
arrester on safe area.

Classification with Current Outputs

Europe (VTT)

EU (94/9/EC, ATEX100a) II 1 G Ex ia IIC T4 Ga

VTT 09 ATEX 028 X issue No: 1

Safety factors Ui= 28 V, Ii= 100 mA, Pi=700 mW

Ci= 1 nF, Linegligibly low

Environmental specifications T

Dust classification (with protection cover) II 1 D (IP65 T = 70 °C)

IECEx (VTT) Ex ia IIC T4 Ga

Safety factors Ui= 28 V, Ii= 100 mA, Pi=700 mW

= -40 ... +60 °C (-40 ... +140 °F)

amb

P

= 0.8 ... 1.1 bar

amb

VTT 04 ATEX 023X

IECEx VTT 09.0002x issue No:1

Ci= 1 nF, Linegligibly low

Environmental specifications T

= -40 ... +60 °C (-40 ... +140 °F)

amb

P

= 0.8 ... 1.1 bar

amb

USA (FM) Classes I, II, III

Division 1, Groups A - G
Division 2, Groups A - D, F and G
FM Project ID: 3010615

Safety factors V

= 28 VDC, I

max

= 1 nF, Li= 0, Pi= 0.7 W

C

i

T

= 60 °C (140 °F), T5

amb

max

= 100 mA

Japan (TIIS) Ex ia IIC T4

Code number: TC17897

Safety factors Ui= 28 VDC, Ii= 100 mA, Ci=1nF

Pi= 0.7 W, Li= 0, T

amb

= 60 °C (140 °F)

VAISALA_______________________________________________________________________ 77

User’s Guide______________________________________________________________________

Canada (CSA)

Class I Division 1 and Division 2

Groups A, B, C, D

Class II Division 1 and Division 2

Groups G and Coal Dust

Class III CSA File No: 213862 0 000

CSA report: 1300863

Safety factors T

= 60 °C, T4,

amb

Intrinsically safe when connected as per
Installation Drawing DRW213478

China (PCEC) Ex ia II CT4

Certificate No. CE092145
Standard GB3836.1-2000 and
GB3836.4-2000

Russia (GOST) 1Ex ia IIC T4

Certificate No. ROSS FI.GB05.V03489

Safety factors Ui= 28 V, Ii= 100 mA, Pi= 700 mW,

Ci= 1 nF, Li=0 H, T

amb

Options and Accessories

Table 14 Options and Accessories

Item Description / Order Code

MODULES
Analog Output Module HM360AOUTSP

= -40 ... +60 °C

SENSORS

®

HUMICAP
HUMICAP
HUMICAP

FILTERS
Sintered Stainless Steel Filter HM47280SP
Stainless Steel Filter HM47453SP
Stainless Steel Filter with Membrane 214848SP
PPS Plastic Grid with Stainless Steel

Netting
PPS Plastic Grid Filter DRW010276SP

TRANSMITTER MOUNTING ACCESSORIES
Wall Mounting Kit HM37108SP
Rain shield 215109

78 ___________________________________________________________________ M010056EN-I

180

®

180R

®

180L2

HUMICAP180
HUMICAP180R
HUMICAP180L2

DRW010281SP

Chapter 9 ____________________________________________________________ Technical Data

Table 14 Options and Accessories (Continued)

Item Description / Order Code

Protection cover (for use in the
presence of combustible dust, ATEX)

PROBE MOUNTING ACCESSORIES
HMT363/HMP363
Duct Installation Kit 210697
Cable Gland M20×1.5 with Split Seal HMP247CG
Swagelok for 12mm Probe 3/8" ISO

Thread
Swagelok for 12mm Probe 1/2" NPT

Thread

HMT364/HMP364
Fitting Body M22×1.5 17223SP
Fitting Body NPT1/2 17225SP

HMT365/HMP365
Mounting Flange 210696
Cable Gland M20×1.5 with Split Seal HMP247CG

214101

SWG12ISO38

SWG12NPT12

HMT367/HMP367
Duct Installation Kit 210697
Cable Gland M20x1.5 with Split Seal HMP247CG
Swagelok for 12mm Probe 3/8" ISO

Thread
Swagelok for 12mm Probe 1/2" NPT

Thread

HMT368/HMP368
Fitting Body ISO1/2 Solid Structure DRW212076SP
Fitting Body NPT1/2 Solid Structure NPTFITBODASP
Fitting Body Set ISO 1/2 ISOFITBODASP
Fitting Body Set (ISO 1/2 + NPT 1/2) THREADSETASP
Leaking Screw with Allen Key 216027
Thread Adapter ISO1/2 to NPT1/2 210662SP
Sampling Cell with Female

Connectors
Sampling Cell with Swagelok

Connectors
Ball Valve ISO1/2 with Welding Joint BALLVALVE-1
Installation Flange ISO1/2 DM240FA
Manual Press HM36854SP

SWG12ISO38

SWG12NPT12

DMT242SC

DMT242SC2

CONNECTION CABLES
Serial Interface Cable 25905ZZ

VAISALA_______________________________________________________________________ 79

User’s Guide______________________________________________________________________

Table 14 Options and Accessories (Continued)

Item Description / Order Code

CABLE BUSHINGS
Cable Gland M20×1.5 for 7.5...12mm

Cable
Cable Gland M20×1.5 for 10...15mm

Cable
Conduit Fitting M20×1.5 for NPT1/2

Conduit
Dummy Plug M20×1.5 for transmitter

body

OTHER
Calibration Adapter for HMK15 211302SP
Galvanic isolator 212483
Barrier 210664

216587SP

216588SP

214780SP

214672SP

80 ___________________________________________________________________ M010056EN-I

Chapter 9 ____________________________________________________________ Technical Data

Accuracy of Calculated Variables

Accuracy of the calculated variables depend on the calibration accuracy of
the humidity and temperature sensors; here the accuracy are given for ±2
%RH and ±0.2 °C.

Accuracy of Dewpoint Temperature °C

Relative humidity

Temp.102030405060708090100

-40 1.86 1.03 0.76 0.63 0.55 0.5 0.46 0.43 — —

-20 2.18 1.19 0.88 0.72 0.62 0.56 0.51 0.48 — —
0 2.51 1.37 1 0.81 0.7 0.63 0.57 0.53 0.5 0.48
20 2.87 1.56 1.13 0.92 0.79 0.7 0.64 0.59 0.55 0.53
40 3.24 1.76 1.27 1.03 0.88 0.78 0.71 0.65 0.61 0.58
60 3.6 1.96 1.42 1.14 0.97 0.86 0.78 0.72 0.67 0.64
80 4.01 2.18 1.58 1.27 1.08 0.95 0.86 0.79 0.74 0.7
100 4.42 2.41 1.74 1.4 1.19 1.05 0.95 0.87 0.81 0.76
120 4.86 2.66 1.92 1.54 1.31 1.16 1.04 0.96 0.89 0.84
140 5.31 2.91 2.1 1.69 1.44 1.26 1.14 1.05 0.97 0.91
160 5.8 3.18 2.3 1.85 1.57 1.38 1.24 1.14 1.06 0.99

Accuracy of Mixing Ratio g/kg

(Ambient pressure 1013 mbar)

Relative humidity

Temp.102030405060708090100

-40 0.003 0.003 0.003 0.003 0.003 0.004 0.004 0.004 — —

-20 0.017 0.018 0.019 0.021 0.022 0.023 0.025 0.026 — —
0 0.08 0.09 0.09 0.1 0.1 0.11 0.11 0.12 0.13 0.13
20 0.31 0.33 0.35 0.37 0.39 0.41 0.43 0.45 0.47 0.49
40 0.97 1.03 1.1 1.17 1.24 1.31 1.38 1.46 1.54 1.62
60 2.68 2.91 3.16 3.43 3.72 4.04 4.38 4.75 5.15 5.58
80 6.73 7.73 8.92 10.34 12.05 14.14 16.71 19.92 24.01 29.29
100 16.26 21.34 28.89 40.75 60.86 98.85 183.66 438.56 — —
120 40.83 74.66 172.36 — — — — — — —

VAISALA_______________________________________________________________________ 81

User’s Guide______________________________________________________________________

Accuracy of Wet Bulb Temperature °C

Relative humidity

Temp.102030405060708090100

-40 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 — —

-20 0.21 0.21 0.22 0.22 0.22 0.22 0.23 0.23 — —
0 0.27 0.28 0.28 0.29 0.29 0.29 0.3 0.3 0.31 0.31
20 0.45 0.45 0.45 0.44 0.44 0.44 0.43 0.43 0.42 0.42
40 0.84 0.77 0.72 0.67 0.64 0.61 0.58 0.56 0.54 0.52
60 1.45 1.2 1.03 0.91 0.83 0.76 0.71 0.67 0.63 0.6
80 2.23 1.64 1.32 1.13 0.99 0.89 0.82 0.76 0.72 0.68
100 3.06 2.04 1.58 1.31 1.14 1.01 0.92 0.85 0.8 0.75
120 3.85 2.4 1.81 1.48 1.28 1.13 1.03 0.95 0.88 0.83
140 4.57 2.73 2.03 1.65 1.41 1.25 1.13 1.04 0.97 0.91
160 5.25 3.06 2.25 1.82 1.55 1.37 1.24 1.13 1.05 0.99

Accuracy of Absolute Humidity g/m

Relative humidity

Temp.102030405060708090100

-40 0.004 0.004 0.005 0.005 0.005 0.006 0.006 0.006 — —

-20 0.023 0.025 0.027 0.029 0.031 0.032 0.034 0.036 — —
0 0.1 0.11 0.12 0.13 0.13 0.14 0.15 0.15 0.16 0.17
20 0.37 0.39 0.41 0.43 0.45 0.47 0.49 0.51 0.53 0.55
40 1.08 1.13 1.18 1.24 1.29 1.34 1.39 1.44 1.49 1.54
60 2.73 2.84 2.95 3.07 3.18 3.29 3.4 3.52 3.63 3.74
80 6.08 6.3 6.51 6.73 6.95 7.17 7.39 7.61 7.83 8.05
100 12.2 12.6 13 13.4 13.8 14.2 14.6 15 15.3 15.7
120 22.6 23.3 23.9 24.6 25.2 25.8 26.5 27.1 27.8 28.4

3

140 39.1 40 41 42 43 44 45 45.9 46.9 47.9
160 63.5 64.9 66.4 67.8 69.2 70.7 72.1 73.5 74.9 76.4

82 ___________________________________________________________________ M010056EN-I

Appendix A ______________________________________________________________ Dimensions

APPENDIX A

DIMENSIONS

This Appendix contains parts drawings of the transmitter housing, probes
and some transmitter mounting accessories with metric and nonmetric
dimensions specified.

HMP361

0603-042

VAISALA_______________________________________________________________________ 83

User’s Guide______________________________________________________________________

HMP363

0603-015

HMP364

HMP365

0603-016

0603-017

84 ___________________________________________________________________ M010056EN-I

Appendix A ______________________________________________________________ Dimensions

HMP367

0603-018

HMP368

0603-019

VAISALA_______________________________________________________________________ 85

User’s Guide______________________________________________________________________

Mounting Plate

Rain Shield

0603-041

86 ___________________________________________________________________ M010056EN-I

Appendix A ______________________________________________________________ Dimensions

Protection Cover

0505-304

VAISALA_______________________________________________________________________ 87

User’s Guide______________________________________________________________________

88 ___________________________________________________________________ M010056EN-I

Appendix B ______________________________________ Wiring for Intrinsically Safe Operation, FM

APPENDIX B

WIRING FOR INTRINSICALLY SAFE
OPERATION, FM

This appendix contains the wiring diagram for intrinsically safe operation
approved by Factory Mutual (FM).

VAISALA_______________________________________________________________________ 89

User’s Guide______________________________________________________________________

-Ch2+

HMT360 connection board

-Ch1+

Material Weigh t

DIMENSIONS ARE IN
MILLIMETERS, UNLESS
OTHERWISE SPECIFIED

FIRST ANGLE PROJECTION

Finish

DOCUMEN T CRE ATION D ATA

YYYY-MM-DD INITIAL S

Creator

Approved

Review

Archive ID

code

Supplier

Scale

Size

Title

General tolerance

Design

Code

Sheet of

Rev

REV

QTY

DESCRIPTION / INFO / ECO No.

DESIGN

ACCEPTED / ApprovedCHECKED / Reviewed

90 ___________________________________________________________________ M010056EN-I

0505-305

Appendix C_____________________________________ Wiring for Intrinsically Safe Operation, CSA

APPENDIX C

WIRING FOR INTRINSICALLY SAFE
OPERATION, CSA

This appendix contains the wiring diagram for intrinsically safe operation
approved by the Canadian Standards Association (CSA).

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0505-306

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Appendix D______________________________________________________________ Certificates

APPENDIX D

CERTIFICATES

This Appendix contains copies of the EXi intrinsically safe certificates
issued for the HMT360 series.

- VTT IECEx Certificate

- VTT ATEX Certificates

- FM Certificate of Compliance

- CSA Certificate of Compliance

- TIIS Certificate of Compliance

- PCEC Conformity Certificate

- GOST Certificate of Conformity

VAISALA_______________________________________________________________________ 93

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1106-007

Figure 28 VTT IECEx Certificate page 1/4

94 ___________________________________________________________________ M010056EN-I

Appendix D______________________________________________________________ Certificates

1106-008

Figure 29 VTT IECEx Certificate page 2/4

VAISALA_______________________________________________________________________ 95

User’s Guide______________________________________________________________________

1106-009

Figure 30 VTT IECEx Certificate page 3/4

96 ___________________________________________________________________ M010056EN-I

Appendix D______________________________________________________________ Certificates

1106-010

Figure 31 VTT IECEx Certificate page 4/4

VAISALA_______________________________________________________________________ 97

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1002-091

Figure 32 VTT ATEX 028X Certificate page 1/2

98 ___________________________________________________________________ M010056EN-I