Vaisala MMT162 User Manual
USER'S GUIDE
Vaisala HUMICAP® Moisture and
Temperature Transmitter for Oil
MMT162
M210934EN-C
PUBLISHED BY
Vaisala Oyj Phone (int.): +358 9 8949 1
P.O. Box 26 Fax: +358 9 8949 2227
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 ............................................................................ 5
About This Manual ................................................................... 5
Contents of This Manual ....................................................... 5
Version Information ............................................................... 6
Related Manuals ................................................................... 6
Documentation Conventions ................................................. 6
Safety ......................................................................................... 7
Recycling .................................................................................. 7
Regulatory Compliances ......................................................... 7
Trademarks ............................................................................... 8
License Agreement .................................................................. 8
Warranty .................................................................................... 8
CHAPTER 2
PRODUCT OVERVIEW .................................................................................. 9
Introduction to MMT162 ........................................................... 9
Basic Features and Options .................................................. 10
Transmitter Structure ............................................................. 11
Typical Applications .............................................................. 12
Method Used for Measuring Moisture in Oil ........................ 12
Lubrication Oil ..................................................................... 12
Transformer Oil ................................................................... 13
CHAPTER 3
INSTALLATION ............................................................................................ 15
Installing the Transmitter ...................................................... 15
Wiring ...................................................................................... 17
Connection Cables .............................................................. 18
Power Supply Requirements ............................................... 19
CHAPTER 4
OPERATION ................................................................................................. 21
Getting Started ....................................................................... 21
Analog Output Operation Modes .......................................... 21
Normal Operation Mode and Malfunction Alarm ................. 21
Limit Alarm .......................................................................... 22
Serial Communication ........................................................... 22
Connecting to Serial Interface ............................................. 22
Installing the Driver for the USB Cable ............................... 23
Terminal Program Settings ................................................. 24
List of Serial Commands ....................................................... 26
Device Information and Status ............................................. 27
Show Device Information .................................................... 27
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User's Guide ______________________________________________________________________
Show Firmware Version ...................................................... 27
Configuring Serial Line Operation ........................................ 28
Set Serial Line Settings ....................................................... 28
Set Serial Line Response Time ........................................... 29
Set Transmitter Address ...................................................... 29
Format Measurement Output .............................................. 30
Select Unit ........................................................................... 32
Set Serial Interface Mode .................................................... 33
Configuring Measurement Parameters ................................ 33
Select Analog Output Parameter and Scaling ..................... 33
Set Analog Output Mode (mA/V) ......................................... 34
Calibrate Analog Output ...................................................... 34
Set Malfunction Alarm Output for Analog Channels ............ 35
Set Alarm Limits and LED Indication for Analog Outputs.... 35
Set Voltage for LED Alarm .................................................. 36
Extend Analog Output Range .............................................. 36
Serial Line Output Commands .............................................. 37
Start Measurement Output .................................................. 37
Stop Measurement Output .................................................. 37
Set Output Interval............................................................... 38
Output Reading Once .......................................................... 38
Troubleshooting Commands ................................................. 39
Display the Currently Active Errors ..................................... 39
Test Analog Outputs ............................................................ 39
Other Commands ................................................................... 40
Opening the Transmitter in POLL Mode ............................. 40
Closing the Connection to a Transmitter in POLL Mode ..... 40
Display Command List ........................................................ 41
Reset Transmitter ................................................................ 42
Restore Factory Settings ..................................................... 42
ppm Conversion ..................................................................... 43
MMT162 ppm Conversion for Transformer Oils .................. 43
Conversion Model with Average Coefficients ...................... 43
Conversion Model with Oil-specific Coefficients ................. 44
Setting Oil Coefficients Using Serial Line ............................ 44
OIL .................................................................................. 44
Determination of Oil-Specific Coefficients ........................... 45
CHAPTER 5
MAINTENANCE ............................................................................................ 47
Cleaning ................................................................................... 47
Changing the Filter ................................................................. 48
Changing the Sensor ............................................................. 48
Error States ............................................................................. 48
Unknown Serial Settings ....................................................... 49
Technical Support .................................................................. 50
Product Returns...................................................................... 50
CHAPTER 6
CALIBRATION AND ADJUSTMENT ........................................................... 51
MM70 in Checking and Adjusting ......................................... 52
One-Point Relative Humidity Adjustment ............................ 52
Using Serial Line ................................................................. 52
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CRH ............................................................................... 52
Using MI70 .......................................................................... 53
One-Point Temperature Adjustment .................................... 56
Using Serial Line ................................................................. 56
Using MI70 .......................................................................... 57
Analog Output Adjustment.................................................... 58
CHAPTER 7
TECHNICAL DATA ...................................................................................... 59
Measured Parameters ............................................................ 59
Operating Environment ......................................................... 60
Inputs and Outputs ................................................................ 60
Mechanics ............................................................................... 60
Spare Parts and Accessories ................................................ 61
Dimensions in mm (inches) .................................................. 62
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List of Figures
Figure 1 Moisture and Temperature Transmitter for Oil MMT162 .......... 11
Figure 2 Water Solubility of Transformer Oils versus Temperature ....... 14
Figure 3 Removing the Transportation Protection Cap .......................... 15
Figure 4 Installing the Transmitter .......................................................... 16
Figure 5 Connecting the Cable ............................................................... 16
Figure 6 Connectors I and II ................................................................... 17
Figure 7 Connector Pinout ...................................................................... 17
Figure 8 Cable with Threaded Connector ............................................... 18
Figure 9 Cable with 90° Angle Threaded Connector .............................. 18
Figure 10 LED Cable ................................................................................ 19
Figure 11 USB Serial Interface Cable ....................................................... 19
Figure 12 PuTTY Terminal Application ..................................................... 25
Figure 13 Metal Housing Transmitter Dimensions ................................... 62
Figure 14 Plastic Housing Transmitter Dimensions .................................. 63
List of Tables
Table 1 Manual Revisions ....................................................................... 6
Table 2 Related Manuals ......................................................................... 6
Table 3 Parameters Measured and Calculated by MMT162 ................... 9
Table 4 Default Serial Interface Settings ............................................... 23
Table 5 Serial Line Commands ............................................................. 26
Table 6 FORM Command Modifiers ...................................................... 31
Table 7 Symbols Used in FORM Checksum Equations ........................ 32
Table 8 Analog Output Modes ............................................................... 34
Table 9 Error Messages ........................................................................ 49
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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 Vaisala HUMICAP® Moisture and Temperature Transmitter
for Oil MMT162.
Contents of This Manual
This manual consists of the following chapters:
- Chapter 1, General Information, provides general notes for the manual
and the product.
- Chapter 2, Product Overview, introduces the features, advantages, and
the product nomenclature
- Chapter 3, Installation, provides you with information that is intended
to help you install the product.
- Chapter 4, Operation, provides information that is needed in basic
maintenance of the product.
- Chapter 5, Maintenance, provides information that is needed in basic
maintenance of the product.
- Chapter 6, Calibration and Adjustment, provides information that is
needed in calibration and adjustment of the product.
- Chapter 7, Technical data, provides the technical data of the product.
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Manual Code
Description
M210934EN-C
April 2013. This manual. Updated descriptions of
Updated list of spare parts and accessories.
M210934EN-B
March 2009. Previous version. Updated cable
specification.
Manual Code
Manual Name
M210935EN
MMT162 Quick Reference Guide
Warning alerts you to a serious hazard. If you do not read and follow
instructions very carefully at this point, there is
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
Version Information
Table 1 Manual Revisions
connection cables and serial line commands.
Related Manuals
Table 2 Related Manuals
Documentation Conventions
WARNING
CAUTION
NOTE
Throughout the manual, important safety considerations are highlighted
as follows:
a risk of injury or even
information on using the product.
6 ___________________________________________________________________ M210934EN-C
Chapter 1 ________________________________________________________ General Information
Ground the
periodically to minimize shock hazard.
Do not modify the unit. Improper modification can damage the product
or lead to malfunction.
Recycle all applicable material.
Dispose of
not dispose of with regular household refuse.
Safety
The Vaisala HUMICAP® Moisture and Temperature Transmitter for Oil
MMT162 delivered to you has been tested for safety and approved as
shipped from the factory. Note the following precautions:
WARNING
CAUTION
Recycling
product, and verify outdoor installation grounding
batteries and the unit according to statutory regulations. Do
Regulatory Compliances
Vaisala HUMICAP® Moisture and Temperature Transmitter for Oil
MMT162 is in conformity with the following EU directive:
- EMC-Directive
Conformity is shown by compliance with the following standards:
- EN 61326-1: Electrical equipment for measurement, control and
laboratory use - EMC requirements - Industrial environment.
- EN 55022 Class B: Information technology equipment – Radio
disturbance characteristics – Limits and methods of measurement.
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User's Guide ______________________________________________________________________
Trademarks
HUMICAP® is a registered trademark of Vaisala Oyj.
Windows® is a registered trademark of Microsoft Corporation in the
United States and/or other countries.
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 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.
8 ___________________________________________________________________ M210934EN-C
Chapter 2 __________________________________________________________ Product Overview
Parameter
Abbreviation
Metric Unit
Non Metric Unit
Water activity
Aw
Temperature
T
°C
°F
Mass concentration of
water in oil
ppm
ppm is
CHAPTER 2
PRODUCT OVERVIEW
This chapter introduces the features, advantages, and the product
nomenclature of Moisture and Temperature Transmitter for Oil
MMT162.
Introduction to MMT162
The MMT162 transmitter is a microprocessor based instrument for the
measurement of moisture in terms of water activity, for example in the
lubrication of circulation systems or in transformer oil. The probe
incorporates a capacitive thin film sensor. The operation of the sensor is
based on changes in its capacitance as the thin polymer film absorbs
water molecules.
NOTE
The MMT162 transmitter is available with either metal or plastic
housing. The transmitter can be configured in many ways: two analog
output signals can be scaled, the measurement ranges can be changed
within certain limits and there are two mechanical connection options,
ISO and NPT 1/2. The MMT162 probe is supplied with a three or five
meter connection cable.
The MMT162 also provides for accurate temperature measurement. It is
an easy-to-install on-line probe which can be calibrated against, for
example, traceable salt solutions.
Table 3 Parameters Measured and Calculated by MMT162
only applicable to transformer oil.
Vaisala HUMICAP® Moisture and Temperature Transmitter for Oil
MMT162 provides reliable moisture measurement in wide range of
applications. Analog outputs can be chosen between current and voltage
signals. Alternatively, digital output RS-485 comes as standard.
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User's Guide ______________________________________________________________________
Basic Features and Options
- Two analog outputs
- Digital output: RS-485
- USB connectivity for service connections via the optional
USB M8 cable
- Different cable lengths available
- Available with two different thread options: ISO G1/2" and NPT 1/2"
- Low maintenance requirements due to excellent long term stability
- LED cable option that enables a visual alarm function
- Field calibration possible with MM70
- Two filter types available: stainless steel grid filter and high flow
stainless steel grid filter (> 1 m/s)
10 __________________________________________________________________ M210934EN-C
Chapter 2 __________________________________________________________ Product Overview
where
1 = 4-pin M8 connector I: analog output channels and operating
power
2 = 4-pin M8 connector II (shown with protective cap):
digital output (RS-485) and operating power
3 = 30 mm nut
4 = HUMICAP® sensor protected with stainless steel grid filter
5 = Connection thread: ISO G1/2" or NPT 1/2"
Transmitter Structure
The structure of the MMT162 is shown in Figure 1 on page 11. The
transmitter body does not have user serviceable parts inside, and is not
designed to be opened. Opening the transmitter will void the warranty.
When the transmitter is delivered, the filter is protected by a yellow
transport protection cap. Remove the transport protection cap before
installing the transmitter.
0805-007
Figure 1 Moisture and Temperature Transmitter for Oil
MMT162
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User's Guide ______________________________________________________________________
To avoid self
errors, make sure there is some flow in the application
Typical Applications
Method Used for Measuring Moisture in Oil
The MMT162 transmitter measures water in oil in terms of water activity
(aw) which can be determined as follows: water activity indicates the
amount of water on the scale of 0 - 1 aw. In this scale, 0 aw is an
indication of completely water free oil and 1 aw an indication of oil fully
saturated with water. Water is present in free form.
The most important feature which distinguishes the measurement of
water activity (aw) from the traditional measurement of absolute water
content (in ppm) is that the saturation point remains stable regardless of
the oil type or the aging of oil, additives used etc. As water activity
exceeds 0.9 aw in any system, there is a risk for segregation (especially if
the temperature decreases).
NOTE
The water activity is used for alarming at the point of >0.9 aw that the
risk for free water in the system is obvious. The most important
advantages of this system are the fact that water activity is immune to the
aging of oil and to additives, and that the MMT162 transmitter can be
used for continuous on-line measurements. In addition, the MMT162 can
be calibrated against salt solutions and no reference oils are needed.
-heating of the probe and consequential measurement
process.
Lubrication Oil
In many industrial plants, like paper mills, hydro power plants and offshore wind turbines, there is a certain amount of free moisture constantly
present. This means that there is a high risk of the free moisture
becoming into contact with the machine bearings. The most common
reasons for the entrance of water are inadequate sealing of the housing or
moisture absorption from ambient air. Accidental leakages from oil
coolers and other equipment can also cause damage.
Free water in lubrication oil prevents oil from forming a uniform layer on
the metal surfaces and thus deteriorating its lubrication properties. This
can cause, for example, spot heating, cavitation, corrosion and micro
pitting. Free water also ruins additives like AW (antiwear) and EP
(extreme pressure). Note that bearings should never be exposed to oils
that have high water content; this is also important during standstill
because the risk for corrosion increases as the oil temperature decreases.
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Chapter 2 __________________________________________________________ Product Overview
It is essential to monitor the water content and to keep it on a suitable
level, meaning below saturation.
When measuring the water content of oil, it is best to measure the water
activity before an oil reservoir and from a pressure line flow. This way
the performance of dehumidifiers can be kept under control to ensure that
no free water reaches the bearings.
Transformer Oil
The determination of moisture in oil is an essential part of a
comprehensive transformer maintenance program. Aging and
deterioration increase the capacity of oil to absorb water. The primary
interest in transformers is to measure the water not in oil but in the
cellulosic insulation around the transformer windings. Heating and
cooling have a considerable effect on moisture levels in oil. While
temperature rises, the paper insulation of transformers tends to loose
moisture which is absorbed by the oil surrounding it. Saturation level is
thus a true indicator of moisture present. The MMT162 method provides
for a reliable detection of the aging of oil and possible leakages.
Oil immersed transformers rely on the oil for cooling, protection from
corrosion and as an important component of their insulation. Excessive
moisture content in oil causes accelerated ageing of the insulation
materials and reduces their dielectric strength. In extreme cases this can
result in arcing and short circuits within the windings. Accurate moisture
measurements can also warn about leaks in the oil system, as water is
absorbed from the surrounding air.
Heating and cooling of a transformer affect moisture levels in oil. This is
due to the fact that the water solubility of oil is temperature dependent. In
general, water solubility increases as temperature rises; see Figure 2 on
page 14 below. Changes in temperature also have an effect on water
desorption of the paper insulation around the transformer windings.
Desorption of water from the insulation increases as temperature rises
and the surrounded oil absorbs desorbed water. Moisture level in oil is
thus a true indicator of moisture present in the paper insulation.
In addition, it must be noted that capacity of oil to absorb water depends
both on the chemical structure of the oil and the additives.
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User's Guide ______________________________________________________________________
WATER SOLUBILITY IN MINERAL TRANSFORMER OIL
10
100
1000
10000
0 10 20 30 40 50 60 70 80 90 100
Temperature (°C)
average water
solubility
range of
variation due to
oil type
range of
variation due to
oil type
0510-029
Figure 2 Water Solubility of Transformer Oils versus
Temperature
The margins show the range of variation of water solubility found in
mineral oils.
14 __________________________________________________________________ M210934EN-C
Chapter 3 _______________________________________________________________ Installation
CHAPTER 3
INSTALLATION
This chapter provides you with information that is intended to help you
install the product.
Installing the Transmitter
After selecting a suitable measurement location, follow the procedure
below to install the transmitter:
1. Remove the yellow transport protection cap from the transmitter.
0805-005
Figure 3 Removing the Transportation Protection Cap
2. Prepare the sealing of the connection:
- If the transmitter has a parallel ISO G1/2" thread, place the
sealing ring at the base of the thread. Always use a new
sealing ring; do not re-use a previously installed one.
- If the transmitter has an NPT 1/2" thread, do not use the
sealing ring. Instead, apply PTFE tape or suitable paste
sealant to the thread. Follow the application instructions of
the sealant.
3. Make sure that the threads on the mounting point are of the correct
type, and fasten the transmitter to the measurement point. Use your
hands to turn the probe until it feels tight. Do not use force at this
point, and check that the sealing ring
(if used) remains centered.
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User's Guide ______________________________________________________________________
Only tighten the probe from the 30
other points in the probe body.
CAUTION
0805-006
Figure 4 Installing the Transmitter
4. Use a 30 mm wrench to tighten the connection to 25 Nm, as shown
in Figure 4 above. If you do not have a 30 mm wrench, use a
1 3/16” wrench or an adjustable wrench instead.
mm nut. Do NOT apply force to
5. Connect the wires of the connection cable.
6. Plug in the cable to the transmitter. Be sure to use the correct
7. Cover the unused connector on the transmitter with the rubber plug
16 __________________________________________________________________ M210934EN-C
0710-130
Figure 5 Connecting the Cable
connector; refer to section Wiring on page 17.
that is attached to the transmitter.
Chapter 3 _______________________________________________________________ Installation
Pin I II
Wire Color
1
Vcc
Vcc
Brown
2
Analog output 1
RS-485 B / D-
White
3
GND
GND
Blue
4
Analog output 2 / LED
RS-485 A / D+
Black
Wiring
0707-035
Figure 6 Connectors I and II
VAISALA _______________________________________________________________________ 17
1210-005
Figure 7 Connector Pinout
User's Guide ______________________________________________________________________
Connection Cables
The following connection cable options are available for MMT162:
- Shielded cables with M8 female straight threaded connector
- Cables with M8 female 90° angle threaded connector
- LED cable
- USB serial interface cable
The figures below show the different cable options that are available.
For order codes, see section Spare Parts and Accessories on page 61.
1210-063
Figure 8 Cable with Threaded Connector
1211-024
Figure 9 Cable with 90° Angle Threaded Connector
18 __________________________________________________________________ M210934EN-C
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