Vaisala HMT360 User Manual

USER’S GUIDE

Vaisala HUMICAP® Humidity and

Temperature Transmitter Series HMT360

M010056EN-J

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 2013

No part of this manual may be reproduced, published or publicly displayed
in any form or by any means, electronic or mechanical (including
photocopying), nor may its contents be modified, translated, adapted, sold
or disclosed to a third party without prior written permission of the
copyright holder. Translated manuals and translated portions of
multilingual documents are based on the original English versions. In
ambiguous cases, the English versions are applicable, not the translations.

The contents of this manual are subject to change without prior notice.

This manual does not create any legally binding obligations for Vaisala
towards customers or end users. All legally binding obligations and
agreements are included exclusively in the applicable supply contract or
the General Conditions of Sale and General Conditions of Service of
Vaisala.

________________________________________________________________________________

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

Software License . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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 Spaces . . . . . . . . . . . . . . . . . . . . . . . . . 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

VAISALA________________________________________________________________________ 1

________________________________________________________________________________

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

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

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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Upper Half of Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

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

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

Scaling Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

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

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

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

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

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

Adjustment Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

CRH Relative Humidity Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

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

Output Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

ITEST Testing Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

SEND Outputting Measurement Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

R Activating Continuous Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

S Stopping Continuous Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

INTV Setting Output Interval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

PRES Setting Ambient Pressure for Calculations . . . . . . . . . . . . . . . . . . . . . . . . 56

FILT Output Filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Resetting the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

RESET Transmitter Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

CHAPTER 5

MEASURING AT OVERPRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Pressure Regulator Recommended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

2 _______________________________________________________________________________

________________________________________________________________________________

CHAPTER 6

CALIBRATION AND ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Calibration Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Factory Calibration and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

User Calibration and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Removing the Electronics Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Calculating Correspondence of Current Values and Output Quantities . . . . . . . . . 64

Relative Humidity Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Automatic Two-Point Adjustment (Only HMT360 with Display) . . . . . . . . . . . . . . . . . 65

Manual Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Low End Adjustment (HMT360 without Display) . . . . . . . . . . . . . . . . . . . . . . . . . 67

High End Adjustment (HMT360 without Display) . . . . . . . . . . . . . . . . . . . . . . . . . 68

Low End Adjustment (HMT360 with Display) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

High End Adjustment (HMT360 with Display) . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

One-Point Temperature Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

ACAL Analog Output Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

CHAPTER 7

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Periodical Checking and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Transmitter Housing and Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

CHAPTER 8

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Operation Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Analog Output Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Product Returns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

CHAPTER 9

TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Relative Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Temperature (+ Operating Pressure Ranges) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Water Activity in Jet Fuel Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Calculated Variables (Typical Ranges) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

With HMP361 Probe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

With HMP363, HMP364, HMP365, HMP367 and HMP368 Probes. . . . . . . . . . . 77

Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Classification with Current Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Accuracy of Calculated Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Accuracy of Dewpoint Temperature °C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Accuracy of Mixing Ratio g/kg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Accuracy of Wet Bulb Temperature °C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Accuracy of Absolute Humidity g/m3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

VAISALA________________________________________________________________________ 3

________________________________________________________________________________

APPENDIX A

DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

HMP361 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

HMP363 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

HMP364 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

HMP365 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

HMP367 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

HMP368 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Mounting Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Rain Shield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88

Protection Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

APPENDIX B

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

APPENDIX C

WIRING FOR INTRINSICALLY SAFE OPERATION, CSA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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 62

Figure 25 Connecting Power Supply and Multimeter for Calibration . . . . . . . . . . . . . 63

Figure 26 Display Chart of the Automatic Adjustment Procedure . . . . . . . . . . . . . . . . 66

Figure 27 Accuracy over Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Table 7 Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Table 8 Relative Humidity Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Table 9 Temperature Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Table 10 Water Activity in Jet Fuel Applications Specifications . . . . . . . . . . . . . . . . . 77

Table 11 HMP361 Calculated Variables Specifications . . . . . . . . . . . . . . . . . . . . . . . 77

Table 12 HMP363, HMP364, HMP365, HMP367& HMP368 Probes Calculated

Variables Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Table 13 Output Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Table 14 General Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Table 15 Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

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).

Version Information

Table 1 Manual Revisions

Manual Code Description

M010056EN-J This manual. November 2013.

- Removed Appedix D, Certificates. Copies of
certificates are included in HMT360 Safety Guide
from version M210483EN-E onward.

- Added table of error codes, see Table 7 on page

74.

- Updated section Options and Accessories on

page 81.

M010056EN-I Previous version.

Related Manuals

Table 2 Related Manuals

Manual Code Manual Name

M210185EN Humidity Calibrator HMK15 User's Guide
M210483EN Vaisala Transmitter Series HMT360 Safety Guide

10 ___________________________________________________________________ M010056EN-J

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-J

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.

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 79.

Copies of the certificates and wiring diagrams are provided in the HMT360
Safety Guide (from version M210483EN-E onward). You can download
updated certificates from the HMT360 product page at the Vaisala website:

www.vaisala.com/hmt360.

VAISALA_______________________________________________________________________ 13

User’s Guide ______________________________________________________________________

Trademarks

HUMICAP® is a registered trademark of Vaisala Oyj.

All other trademarks are the property of their respective owners.

Software License

This product contains software developed by Vaisala. Use of the software
is governed by license terms and conditions included in the applicable
supply contract or, in the absence of separate license terms and conditions,
by the General License Conditions of Vaisala Group.

Warranty

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

Please observe that any such warranty may not be valid in case of damage
due to normal wear and tear, exceptional operating conditions, negligent
handling or installation, or unauthorized modifications. Please see the
applicable supply contract or Conditions of Sale for details of the warranty
for each product.

14 ___________________________________________________________________ M010056EN-J

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-J

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-J

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-J

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-J

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-J

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-J

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 56 and Setting the Pressure for
Calculations on page 46.

28 ___________________________________________________________________ M010056EN-J