LSI LASTEM DMA672.1 User manual

Environmental monitoring solutions
Thermohygrometers
User manual

Thermohygrometers –User manual
LSI LASTEM SRL
INSTUM_04246
Pag. 2 / 17
Revisions list
Issue
Date
Description of changes
Origin
14/08/2020
About this manual
The information contained in this manual may be changed without prior notification. No part of this manual
may be reproduced, neither electronically nor mechanically, under any circumstance, without the prior
written permission of LSI LASTEM.
LSI LASTEM reserves the right to carry out changes to this product without timely updating of this document.
Copyright 2020 LSI LASTEM. All rights reserved.

Thermohygrometers –User manual
LSI LASTEM SRL
INSTUM_04246
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Summary
1 Introduction................................................................................................................................................4
2 Versions......................................................................................................................................................5
2.1 DMA672.x models ............................................................................................................................. 5
2.2 DMA867, DMA875, DMA975 and EXP815 models............................................................................ 7
3.1 General safety rules........................................................................................................................... 9
3.2 Mechanical installation and connection............................................................................................ 9
3.2.1 DMA672.x sensors..................................................................................................................... 9
3.2.2 DMA867, DMA875 and DMA975 sensors ............................................................................... 10
3.2.3 EXP815 sensor ......................................................................................................................... 10
3.3 LSI LASTEM data logger configuration............................................................................................. 11
4 Operation check .......................................................................................................................................11
4.1 Calculation of the measurement value based on the sensor analog output .................................. 12
5 Maintenance.............................................................................................................................................12
5.1 Cleaning of the anti-radiant shield and the porous filter................................................................ 12
5.2 Sensing element replacement......................................................................................................... 13
6 Accessories / Spare parts .........................................................................................................................13
7 Disposal ....................................................................................................................................................14
8 How to contact LSI LASTEM......................................................................................................................14
9 CE Conformity Declaration.......................................................................................................................15

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LSI LASTEM SRL
INSTUM_04246
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1Introduction
The LSI LASTEM thermohygrometers featured in this manual are sensors designed even for meteorological
applications. Precise and reliable, this sensor is suitable for continuous meteorological measurements also in
severe environments and in presence of steep thermal and hygrometric variations.
DMA672.1, DMA672.4, DMA672.5 temperature output is Pt100 element and 0÷1 Vdc output for RH%.
DMA672.3 output is 0÷1 Vdc for both Temperature and RH%. DMA672.3 is very suitable for tropical weather
in continuous high temperature and RH conditions. For outdoor application it should be coupled with a anti-
radiant shield.
DMA875 and DMA975 are equipped with a high efficiency natural ventilation anti-radiant shield (with special
black painting on the lower surface of the plates) ensures that the sensing element is protected by sun rays
for accurate air temperature readings. Output of the models DMA975 is RS485 using Modbus RTU® or TTY-
ASCII protocols.
For even better results in low wind and high solar radiation conditions, model DMA867 is equipped with a
forced ventilation shield.
EXP815 model is equipped with an internal radio to send measurement up to 600 m far to data logger
equipped with radio receiver.

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LSI LASTEM SRL
INSTUM_04246
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2Versions
2.1 DMA672.x models
Code
DMA672.1
DMA672.4
DMA672.5
DMA672.3
Output
RH%: 0÷1 Vdc.
°C: Pt100 DIN-IEC
751 table (EN
60751) UART
(Pluvi-ONE, Alpha-
Log)
UART
RH%: 0÷1 Vdc.
°C: Pt100 DIN-IEC
751 table (EN
60751)
2 x 0÷1 V
Power supply
5÷24 Vdc
Power consumption
2 mA
< 5 mA
Cable and connector
L.3 m free wires
(8 wires)
L.1 m + male
connector for
ELU00x
enclosures
L.3 m + male
connector for
DWA9xx extension
cables
L.5 m free wires (8
wires), detachable
Data logger
compatibility
M-Log (ELO008), E-
Log, A-Log, Pluvi-
ONE (uscita
RS232), A-Log
using ALIEM
module
Pluvi-ONE and A-
Log with ELU00x
enclosures
Using DWA9nn:
extension cable: M-
Log (ELO008) E-Log
A-Log using ALIEM
module
M-Log (ELO008)
E-Log, A-Log using
ALIEM module

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INSTUM_04246
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Common technical specifications
Temperature
Principle
RTD Pt100 1/3 DIN B (Class AA EN60751)
Measuring range
-50÷100 °C (DMA672.3: -40÷60 °C)
Accuracy
0.1 °C (@0 °C)
Output
Pt100 DIN-IEC 751 table (EN 60751)
Resolution
0.01 °C (A/M/R/ELog, P1)
Response time (T90)
Typical 4 s (1 m/s air flow)
Long term stability
<0.1 °C/year
Relative Humidity
Principle
Capacitive
Measuring range
0÷100%
Accuracy
±1% (@5÷95%); DMA672.3: 0.5% RH (@10 ÷95%)
Hysteresis
<1%
Resolution
0.1% (A/M/R/ELog, P1). 0.01% configurable on
data logger
Response time (T90)
10 s (1 m/s air flow)
Long term stability
<±1%/year
General Information
Protection type
IP66
Operative temperature
-50÷100 °C

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INSTUM_04246
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2.2 DMA867, DMA875, DMA975 and EXP815 models
Code
EXP815
DMA975
DMA875
DMA867
Measurements
°C/RH%
°C/RH%
°C/RH%
°C/RH%
Output
Radio
RS-485
2 x 0/4÷20 mA
Frequency
868 MHz
-
-
Radio transmission
power
25 ± 3 mW
-
-
Radio transmission
distance (line-of-sight)
600 m
-
-
Transmission rate
10 s
-
-
-
Battery life
>2 years
-
-
-
Communication protocol
-
Modbus RTU,
TTY-ASCII
-
-
Configuration
-
Hyperterminal
-
-
RS485 protection
-
Galvanic insulation
(3 kV, UL1577)
-
-
RS485 speed
-
1200÷115 kbps
-
-
Power supply
Battery (AA 3.6 V)
10÷30 Vac/dc
Power consumption
<10 µW stand-by
120 mW in
transmission
1 W
3 W
Electric protections
NO
(electrically
insulated system
Tranzorb and Emifilter
Ventilation
Natural
Forced
Resolution
Temp: 0.01 °C RH: 0.1%
Dipending on data acquisition

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LSI LASTEM SRL
INSTUM_04246
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Common technical specifications
Temperature
Principle
RTD Pt100 1/3 DIN B (Class AA EN60751)
Measuring range
Programmable: -40÷60 °C, -50÷60 °C, -50÷70 °C,
-30÷100 °C
Accuracy
0.1 °C (@0 °C)
Output
Pt100 DIN-IEC 751 table (EN 60751)
Response time (T90)
Typical 4 s (1 m/s air flow)
Long term stability
<0.1 °C/year
Relative Humidity
Principle
Capacitive
Measuring range
0÷100%
Accuracy
±1% (@5÷95%)
Output
Programmable: RH% or Dew Point
Resolution
0.1%
Response time (T90)
10 s (1 m/s air flow)
Long term stability
<±1%/year
Hysteresis
<1%
General Information
Protection type
IP66
Operative temperature
-40÷80 °C
Data logger compatibility
M-Log (ELO008)
R-Log (ELR515)
E-Log
A-Log using ALIEM module

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LSI LASTEM SRL
INSTUM_04246
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3Installation
For installation, choose a site where conditions are representative of the environment to be examined. The
thermometers and thermohygrometers must be mounted in places where the morphological conditions of
the surfaces, the urban structures and the environmental conditions reflect as much as possible the general
conditions of the site where the measurements are to be made. It is important that, in the areas close to the
installation, there are no structures that can radiate heat (concrete floors, asphalt, walls, etc.) The
thermohygrometer should be installed at a distance of 1.5 - 2 m from the ground (see WMO n ° 8 part 2).
3.1 General safety rules
Please read the following general safety rules in order to avoid injuries to people and prevent damages to
the product or to possible other products connected with it. In order to avoid any damages, use this product
exclusively according to the instructions herein contained.
The installation and maintenance procedures must be carried-out only by authorized and skilled service
personnel.
Power the instrument in a suitable manner. Pay attention and observe the power supplies like indicated for
the model in your possession.
Carry-out all connections in a suitable manner. Pay strict attention to the connection diagrams supplied with
the instrument.
Do not use the product in case of suspected malfunctions. In case of suspected malfunction, do not power
the instrument and contact authorized technical support immediately.
Before you carry-out any operation on electrical connections, power supply system, sensors and
communication apparatus:
•Disconnect the power supply.
•Discharge the accumulated electrostatic discharges touching an earthed conductor or apparatus.
3.2 Mechanical installation and connection
3.2.1 DMA672.x sensors
The installation of the DMA672.x sensors changes according to the type of anti-radiant shield used.

Thermohygrometers –User manual
LSI LASTEM SRL
INSTUM_04246
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➢Using DYA230 natural ventilation anti-radiant shield:
1. Fix the DYA049 supporting collar to the pole at a height of about
1.5 - 2 m.
2. Fix the DYA230 anti-radiant shield to the DYA049 supporting
collar.
➢UsingDYA233 natural ventilation anti-radiant shield:
1. Fix the DYA046 bar on the pole.
2. Fix the DYA233 anti-radiant shield to the DYA046 bar.
➢Using DYA231 forced ventilatione anti-radiant shield:
1. Fix the DYA049 supporting collar to the pole at a height of about
1.5 - 2 m.
2. Fix the DYA231 anti-radiant shield to the DYA049 supporting collar
3. Insert the sensor stem inside the anti-radiant shield. The sensitive elements should result in the
central position on the anti-radiant shield and then secure it using the cable gland.
4. Run the cable to the data logger.
5. Connect the cable to the data logger as specified in the drawing (DISACC) supplied with the sensor.
3.2.2 DMA867, DMA875 and DMA975 sensors
1. Remove the cover from the sensor box and set the dip-switches for:
-0…20 mA or 4…20 mA output
-Temperature measurement range
-Relative Humidity or Dew Point output
2. Fix the cover to the box.
3. Fix the DYA049 supporting collar to the pole at a height of about 1.5 - 2 m.
4. Fix the anti-radiant shield support to the DYA049 supporting collar.
5. Screw the DWA5xx cable connector onto the sensor box.
6. Connect the cable to the data logger as specified in the drawing (DISACC) supplied with the sensor.
3.2.3 EXP815 sensor
1. Fix the DYA049 supporting collar to the pole at a height of about 1.5 - 2 m.
2. Fix the anti-radiant shield support to the DYA049 supporting collar.
3. Remove the cover from the sensor box and move the ignition switch to ON; screw the cover to the
box.
4. Place/install the EXP301 receiver near the PC or data logger.

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INSTUM_04246
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3.3 LSI LASTEM data logger configuration
If the sensor is used with an LSI LASTEM data logger, proceed with the configuration of the data logger using
the 3DOM software:
➢Open the data logger configuration
➢Add the sensor by selecting its code (eg DMA672.1) from the 3DOM Sensor Library.
➢Check the acquisition parameters (input, rate, etc.)
➢Save the configuration and send it to the data logger.
For more information about the configuration, refer to the manual of the data logger in use.
4Operation check
To check the sensor output it is necessary to have the accompanying drawing (DISACC) of the sensor and a
multimeter.
Identify the sensor output (§2). For sensors with analog output (current or voltage), proceed as follows:
➢Current output (0/4÷20 mA):
1. Set the multimeter to measure signals in direct current (DC) and 20 mA scale.
2. Disconnect the wire corresponding to the negative signal (- Sig) and connect it to the red test
lead (+) of the multimeter. The black test lead (-) fix it in place of the disconnected wire.
3. Read the value displayed on the multimeter and apply the formula shown in §4.1.
➢Voltage output (V):
1. Set the multimeter to measure voltage signals and scale in V.
2. Connect the red test lead (+) of the multimeter to the wire corresponding to the positive
signal (+ Sig) and the black test lead (-) to the negative signal wire (- Sig) of the sensor (it is
not necessary to disconnect the sensor from the data logger.)
3. Read the value displayed on the multimeter and apply the formula shown in §4.1.
Verification of the digital output (RS485) can be done using a PC, equipped with an RS232 serial port and in
which the third-party program modpoll (https://www.modbusdriver.com/modpoll.html) is installed.
1. Connect the sensor serial cable to the PC serial port.
2. Open a DOS Prompt window and type the following command (it is assumed that the transmission
parameters are set as follows: Baudrate: 9600 bps, Parity: None and that the PC serial port used is
COM1):
modpoll -a 1 -r 1 -c 3 -t34:float -p none -b 9600 com1 [Enter]
For the list of available commands, type the command modpoll /help.
3. The program displays the values for the following quantities:
Temperature, Relative Humidity, Dew Point.
For more information about the DMA975 sensor, refer to INSTUM_01371 user manual.

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INSTUM_04246
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4.1 Calculation of the measurement value based on the sensor analog output
To calculate the value of the measurement, temperature or relative humidity or dew point, starting from
the current or voltage value, apply the formula:
FORMULA: EXAMPLE:
Mrange
M0= Mlow + · (Uout –Ulow)
Urange
(100-(-50)) °C
M0= -50°C + · (12-4) mA = 25 °C
(20-4) mA
where:
Mlow = lower measurement limit
Mrange = measurement range
Urange = output measurement range (V or mA)
Uout = measured output (V oppure mA)
Ulow = lower output limit (V o mA)
With sensor with the following features:
-Temperature range: -50÷100 °C
-Output measurement range: 4÷20 mA
-Measured output: 12 mA
5Maintenance
This sensor is a precision measurement apparatus. In order to maintain the specified measurement precision
over the time, LSI LASTEM recommends to check it periodically (at least twice a year); it is moreover
suggested the replacement of the measure element according to the place of installation (in persistent
conditions of high humidity, pollution, dust and chemical substances presence, the sensitive element
deteriorate faster than the one placed in a location with less adverse conditions). It is, anyway, a good rule
to replace the sensitive element at least once every two years.
5.1 Cleaning of the anti-radiant shield and the porous filter
Referring to the picture of §5.2, proceed as follow:
1. Remove power from the sensor. Depending on the model, disconnect the cable from the Connector
from DWA cable or from the data logger.
2. Unscrew Shield cable gland and pull down the Stem.
3. Clean the extern side of the Anti-radiant shield with the aid of a small brush or a wet rag.
4. Clean the stem using a wet rag.
5. Unscrew the Porous filter.
6. Clean the filter with a cold air jet.If the filter is particularly damaged, replace it.
After cleaning mount the sensor following the operations described above in reverse order.

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LSI LASTEM SRL
INSTUM_04246
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5.2 Sensing element replacement
The sensing element is mounted on the stem. The stem replacement procedure is similar for all sensors.
Below we refer to the DMA975 model.
1. Remove power from the sensor.
disconnecting the cable from the
Connector from DWA cable of the
Case.
2. Remove the Case cover.
3. Unscrew the wires from the Terminal
block.
4. Unscrew the Case cable gland.
5. Unscrew Shield cable gland and pull
down the Stem.
6. Insert the new Stem in the Shield cable
gland until reaching the reference (the
label); tighten Shield cable gland.
7. Insert the stem cable on Case cable
gland and connect wires on the
Terminal block as reported on the
sensor drawing.
8. Tighten Case cable gland.
9. Montare il coperchio e collegare il cavo
a Connettore cavo DWA.Mount the
case cover and connect the cable to
the Connector for DWA cable.
6Accessories / Spare parts
Code
Description
SVICA0003
ISO9001 type calibration certificate (Temperature)
SVACA0006
ISO17025-ACCREDIA type calibration certificate (Temperature)
SVICA1003
ISO9001 type calibration certificate (RH%)
SVICA1005.1
ISO17025-ACCREDIA type calibration certificate (RH%)
DWA505
Cable L = 5 m
DWA510
Cable L = 10 m
DWA525
Cable L = 25 m
DWA526
Cable L = 50 m
DWA527
Cable L = 100 m
DWA910
Extension cable L.10 m for DMA672.5
DWA925
Extension cable L.25 m for DMA672.5
MG2251
7 pin free female connector
ML3015
Sensitive element (spare part) for EXP815, DMA975-875-867
DYA049
Mast mounting device for Ø 45÷65 mm pipe
EXP301
Radio signal receiver from EXP815 radio sensor (output compatible with data loggers M/E-Log)

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INSTUM_04246
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7Disposal
This product is a device with high electronic content. In accordance with the standards of environmental
protection and collection, LSI LASTEM recommends handling the product as waste of electrical and electronic
equipment (RAEE). Forthis reason, at the end of its life, the instrument must be kept apart from other wastes.
LSI LASTEM is liable for the compliance of the production, sales and disposal lines of this
product, safeguarding the rights of the consumer. Unauthorized disposal of this product
will be punished by the law.
8How to contact LSI LASTEM
In case of problem contact the technical support of LSI LASTEM sending an e-mail to [e-mail],
or compiling the technical support request module at www.lsi-lastem.com.
For further information refer to addresses and numbers below:
•Phone number +39 02 95.414.1 (switchboard)
•Address: Via ex S.P. 161 –Dosso n. 9 - 20049 Settala Premenugo, Milano
•Web site: www.lsi-lastem.com
•Commercial service: [email protected]om
•After-sales service: [email protected]om, Repairs: [e-mail]

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LSI LASTEM SRL
INSTUM_04246
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9CE Conformity Declaration

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LSI LASTEM SRL
INSTUM_04246
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INSTUM_04246
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