Nokeval MTR265B User manual

Nokeval
MTR265B
User Manual

2
Contents
Document information...................................................................................................................................... 2
Introduction....................................................................................................................................................... 3
Warnings............................................................................................................................................................ 3
Trademarks........................................................................................................................................................ 3
Manufacturer .................................................................................................................................................... 3
Description ........................................................................................................................................................ 4
Installation......................................................................................................................................................... 4
Maintenance...................................................................................................................................................... 9
Configuring ...................................................................................................................................................... 11
Troubleshooting .............................................................................................................................................. 13
Specifications................................................................................................................................................... 14
Document information
Device Scope: MTR265B
Firmware Versions: 2.0 - 2.0
Document Type: manual
Document ID: 3321
Document Version: 27
Document Date: 8.11.2013

3
Introduction
MTR265B is IP65 rated wireless transmitter for Pt100, TC and mV inputs. The wireless concept allows easy
installation, implementation and expansion also in difficult installation sites.
Warnings
MTR265B transmitter contains a primary battery and a low-power licence-free ISM band radio
transmitter operating at 433.92 MHz. Observe local regulations concerning the proper disposal of
batteries and the use of the integrated radio transmitter.
Trademarks
Any trademarks mentioned in this manual are the property of the respective trademark owners.
Manufacturer
Nokeval Oy
Yrittäjäkatu 12
37100 Nokia
Finland
Tel [phone] (Mon-Fri 8:30-16:00
EET)
WWW http://www.nokeval.com/
email [email protected]om,
[email protected]m

4
Description
General
MTR265B transmitter is housed in impact resistant plastic enclosure which, when properly screwed
together, is watertight to IP 65. The joint between the two parts is sealed with one rubber O-ring. The
transmitter fulfills the mechanical and measuring accuracy requirements of the EN 13485 standard. It also
conforms to the requirements of the standards EN 13486 and EN 12830 where applicable.
The transmitter is delivered with M12-male connector for connecting cable sensors and with MTR265B-SP
wall mounting bracket for fastening.
MTR265B transmitter operates in license-free 433.92 MHz ISM-band (Industrial, Scientific, Medical). The
power consumption of the radio transmitter is so low, that it does not cause any adverse effects to living
organisms or to other nearby radio transmitters operating on other frequencies.
Each radio transmitter has a unique ID number that is used to distinguish the measuring results coming
from each individual transmitter. The transmitter is attached to the measuring target from the holes of a
MTR265B-SP wall mounting bracket.
Transmitter measures temperature with an external Pt100-sensor. Measuring operation is performed with
24-bit AD converter, a micro controller and a 1.5 V size AAA alkaline battery. In typical use the endurance of
the battery is about one year. Temperature measuring accuracy and stability of the transmitter is very
good.
Nokeval offers wide range of different Pt100- and Pt1000-sensors. The transmitter works also with most
other resistive temperature sensors, like Ni- and Cu-sensors. Sensor is screwed to M12-male connector
delivered with the transmitter and connected to the M12-female connector of the transmitter.
Installation
Preparations
Open MTR265B and install the AAA battery delivered with it according to the polarity markings of
on the circuit board. Installing the battery in a wrong way may break the device.
When screwing the housing together, O-ring is intact and that there is no gap between two parts of the
housing. This is important for ensuring the watertight sealing of the transmitter.
Before installing of the transmitters it’s always a good idea to make an installation plan of all the target
locations and their names. While installing the transmitters it easy to write down the ID numbers of the
transmitters to this plan. This will help when initializing the system.
Maximum number of transmitters
International radio standards limit the use of radio frequencies and they also limit the use of the license-
free ISM frequency band that Nokeval transmitters use. The maximum total number of Nokeval radio
transmitters that can be simultaneously used in the same coverage area depends on the transmit interval.
The following table gives guidelines on the maximum number of transmitters with different setups. The

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default interval is 27 seconds for MTR265B. Transmit interval can be individually adjusted for each
transmitter as instructed in the chapter Configuring.
The following table presents maximum number of transmitters with different intervals and with different
numbers of repeaters.
Interval
Receiver(s) only
Receiver(s) and 1 repeater
Receiver(s) and 2 repeaters
5 s
22
11
7
10 s
43
22
14
20 s
87
43
29
30 s
130
65
43
40 s
174
87
58
50 s
217
109
72
60 s (1 min)
261
130
87
70 s
304
152
101
80 s
348
174
116
90 s
391
196
130
120 s (2 min)
522
261
174
240 s (4 min)
1043
522
348
Dimensions
The following pictures present some dimensions in millimeters:
155155155155
ØØØØ 29292929
174174174174
95
27.5
8.8
8.8
5
5
Ø 4.5
73.5
31.2
23.7
23.2

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The total height of MTR265B is 227 mm including removable connector.
There are two mounting holes on the corners of MTR265B-SP wall mounting bracket which have a diameter
of 4,5 mm. Choose correct type of screws depending on the wall material and with maximum of 4mm
diameter.
Mounting location
Radio technical perspective
MTR265B transmitter has a typical indoor maximum range of 50...100 m depending on the number and
quality of obstacles between the transmitter and the receiver. The best range is achieved when there is a
line-of-sight between the transmitter and receiver. In unrestricted open space (outdoors) the maximum
range can be over 500 meters. Walls and obstacles attenuate the signal and therefore reduce the range.
Especially closed steel structures attenuate radio signals very effectively, and installation in or behind them
should be avoided if possible. In the worst possible conditions, e.g. very thick reinforced concrete walls,
bomb shelters, deep underground spaces, the range can be even less than 10 meters.
However, most spaces with metal walls have doors or openings of some sort, and these openings and the
seals between them and the door, leak radio signals if the seals are made of non-conductive material. As a
rule of thumb the device should be mounted with antenna positioned vertically just like the antenna of the
radio receiver. The doors that leak the radio signals usually have larger vertical dimensions than horizontal
and thus leak the vertically polarized signal from the vertically mounted antenna more effectively.
One more factor that affects the final transmission range and performance is the local radio interference
and noise condition. This should be seriously considered in heavy industrial installation sites or any sites
with lots of power electronics around, for example power inverters and large electric motors. At least the
radio receiver should be located as far as possible from this type of radio interference sources.
In any case, it is worth considering the installation location from the radio technical perspective too.
MTR265B with external sensor gives more flexibility in choosing the installation location of the transmitter
itself. But even for this, the guidelines given in the next chapter should be followed when choosing the
installation location for the external sensor.
Measurement perspective
MTR265B transmitter can be installed in the limits of the length of the sensor form the place where
temperature is to be measured. When choosing the installation location one must consider multiple effects
affecting the temperature distribution in the space.
Considerations for cold storage applications
Air tends to layer such that cooler air is lower and warmer air is higher. Evaporators and fans blow cold air
into their vicinity. Doors, vents, lamps and other heat sources warm up their surroundings. The device or
external sensor should be installed into a spot whose temperature follows as closely as possible to the
temperature of the target products in the same space.
Therefore the device or the sensor should not be installed:
• close to the floor or ceiling,
• onto the floor or ceiling,
• near the evaporator of a refrigeration unit,
• near the place where the cold/hot air flows from the evaporator/radiator,
• near a door or other opening and definitely not above one,
• close to a lamp or other heat source nor
• in a location where it is likely that the device will be covered up or get mechanically damaged.

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A good installation location is:
• on a wall as far away as possible from the door and the evaporator/radiator,
• at a height of about 3/4 of the height of the space,
• and where people rarely move about,
• and where air can freely move around.
Considerations for oven applications
In the oven temperature measuring the maximum temperature of the sensor cable insulation has to be
taken into account. For Teflon-insulated cables maximum is 250 °C. For rubber- and PVC insulated cables
maximum is 105 °C. For glass fiber insulated special cables maximum is 400 °C. In the temperatures over
250 °C it is recommended to install sensor in a way that only metallic sensor head is located inside the hot
space. To get more information about sensors go to www.nokeval.com.
Connections
MTR265B transmitter has a standard 4-pole M12 sensor connector for attaching the sensor. A compatible
M12 plug is supplied with the transmitter. Refer to the following illustration for the pin out of the M12
connector on the transmitter. Connect the sensor wires to the plug according to the numbers.
PT100 connections
2-wire connection is not recommended, because the resistance of the sensor cable itself is not
compensated. Pt100-sensor resistance is 0.385 ohms / °C and because of that it is important to remove the
resistance with 3- or 4-wire connection. Also 2-wire connection can be used if the accuracy is not the main
criteria. Pt100-connections can be extended with normal copper cables.

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Thermocouple connections
Thermocouple sensors have typically 2 meter long cables. If this length is not enough, the sensor cable can
be extended, but this has to be made with correct type of thermocouple cable, copper cable must not be
used. The most common thermocouple is K-type and the correct extension cable for it in below 105 °C
ambient temperature is for example JHAS-K-7/0.2 cable. With higher ambient temperatures teflon covered
extension cables can be used up to 250 °C maximum temperature. MTR265B is factory set for Pt100 3-wire
sensor. Any other sensor settings have to be mentioned when ordering or changed by the customer with
programming cables. To get more information about sensors go to www.nokeval.com.
Nokeval supplies Pt100- (product name TRE) and TC-sensors (product name TCSM12) with M12 male
connector and with different dimensions, all of them can be installed straight to the M12 female connector
of MTR265B. (See picture below)

9
Maintenance
Cleaning
The plastic parts can be cleaned with a soft cloth and soap water. Cleaning with isopropyl alcohol is also
allowed.
When cleaning with liquids, verify that the transmitter housing is securely sealed and screwed
together to prevent liquids from entering the enclosures.
Battery
General
MTR265B is powered by single 1.5 V AAA-size alkaline battery.
Life time
Battery life time depends on the used transmit interval. Ambient temperature also has an effect on the
achievable battery life, which will be significantly shorter in extremely cold and very hot environments. The
following graph gives a rough estimate of battery life with different transmit intervals. It should be noted
that with long transmit intervals, the estimated battery life approaches the typical shelf-life of alkaline
batteries. Thus also the age and quality of the battery affect the resulting battery life time.
Replacing the battery
The battery is user replaceable but it should be done carefully. To replace the battery, follow these steps:
1. Unscrew external sensor from transmitter.
2. Grab top part of the transmitter and pull it off from the wall mounting bracket.
3. Unscrew the enclosure. The meeting is between the main label and the serial number label.
4. Carefully pull the two enclosure parts apart.
0,0
0,5
1,0
1,5
2,0
2,5
010 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250
Years
Transmit interval (s)
Estimated battery life time (25°C)
1,5V 1000mAh AAA size alkaline cell

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5. Replace the battery with a high quality alkaline 1.5 V size AAA battery observing the correct
polarity.
6. Carefully insert the two enclosure parts back together.
7. Screw the enclosure parts back together.
8. Screw the external sensor back to the transmitter.
9. Push the transmitter back to the wall mounting bracket, if using one.
10. Properly dispose the used battery observing the local regulations
Calibration certificates
Individual calibration certificate is available for each calibrated MTR265B transmitter. To avoid printing,
handling, sending and storing a large number of paper certificates that are easily misplaced, all calibration
certificates are always available on Nokeval web site at address www.nokeval.com. On the pages select
Support (top of the page) and then Calibration (left side). Finally select the item Calibration certificates.
See the picture below.
Enter the serial number of the measuring module in question into the text entry box. The serial number has
the format of A123456. The serial number of each measuring module can be found on the big white
colored label, just below the bar code. After entering the serial number just click the button ”Get
certificates”. Now you will see a list of certificates with corresponding dates. Click the PDF link next to the
date to download and view the certificate. Adobe Reader is needed to view the certificates, it can be
downloaded at get.adobe.com/reader.

11
Configuring
Programming cable
MTR265B transmitter has an internal Conf-programming connector, found on many other Nokeval products
as well. Transmitter enclosure must be opened in order to reveal this connector and to be able to connect
the programming cable.
The following programming cables are available:
6790 Hand held programmer + POL3-PIN adapter
MekuWin program + DCS772 USB-POL-converter + POL3-pin adapter
MekuWin program + POL-RS232 programming cable + POL3-PIN adapter
A free Windows program Nokeval MekuWin is available in the address www.nokeval.com in the location
Software » Configuration software » MekuWin. The same location also includes user manual of MekuWin
which includes more information on using MekuWin.
The communications parameters for MTR265B transmitters are always:
Protocol
SCL
Baud
9600
Parity
8N1
Address
0
Menu
All common settings are located under Conf menu.
Conf
In
Out Out
Period
In
Sensor
R0
4W
Pts
Mea1
Sca1
Mea2
Sca2

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In / Sensor
This setting selects the sensor type which can be one of the following values:
Value
Description
Pt
Standard platinum RTDs (IEC 60751)
Ni
Nickel RTDs
Cu
Copper RTDs
Ohm
No sensor linearization, result of resistance measurement is sent in Ohms
mV
Voltage input -30…2000 mV
Tc
Thermocouple sensor with Receiver side linearization
TcB
Linearization for B-type thermocouple
TcC
Linearization for C-type thermocouple
TcD
Linearization for D-type thermocouple
TcE
Linearization for E-type thermocouple
TcG
Linearization for G-type thermocouple
TcJ
Linearization for J-type thermocouple
TcK
Linearization for K-type thermocouple
TcL
Linearization for L-type thermocouple
TcN
Linearization for N-type thermocouple
TcR
Linearization for R-type thermocouple
TcS
Linearization for S-type thermocouple
TcT
Linearization for T-type thermocouple
In / R0
This setting defines the resistance of the sensor element in reference temperature (0 °C). For Pt100 the
default value is 100 and for Pt1000 it is 1000. If a more accurate value is known for the sensor in question,
it can be entered here to obtain more accurate results
In / 4W
This setting has to be enabled when using four of two wire RTD sensors.
In / Pts
This setting defines scaling. Possible values are 0, 1ja 2.
Value
Description
0
No scaling
1
One-point (offset) scaling (Uncal1 and Cal1 settings are visible)
2
Two-point scaling (Uncal1, Cal1, Uncal2 and Cal2 settings are visible)
Out / Period
This sets the transmit period or interval of all measurement results. Allowed range is from 2 to 127 units.
This corresponds to an approximate range of 5 seconds to 5 minutes and 43 seconds because each unit
represents about 2.7 seconds in room temperature. Actual transmit interval varies slightly depending on
ambient temperature. This variation is intentional to reduce the chance of collisions between transmitters.
This setting has a direct effect on battery endurance. Avoid using unnecessarily short transmit intervals
because this causes the battery to drain faster and also limits the maximum number of wireless
transmitters that can be used in the same coverage area. Refer to the Installation chapter’s table for
maximum number of transmitters with each period value and Maintenance chapter’s Battery topic for
more information on battery endurance.

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Troubleshooting
No radio reception
If the radio packets of this transmitter cannot be received and the operation of the receiving system
has already been verified according to their manuals and preferably also with a transmitter known to
work, then the following should be checked:
1. Transmitter has an internal LED component in the middle part of the circuit board. Screw enclosure
open and observe if the LED blinks every time there is a transmission.
2. If the above checks fail, attach POL3-PIN-adapter connected to programming cable to the
transmitters internal Conf-connector. Check transmitter settings and battery voltage from the
menu with MekuWin program. For more information on programming cables and configuration
menu, refer to chapter Configuration.
3. If configuration attempts fail, remove battery and re-insert it to rule out any contact disturbances
and try configuring the device again.
4. If the device still fails to respond to configuration attempts, replace the battery with a new one and
retry configuring. If the transmitter is working and the battery is found to be fine, then try
reorienting or relocating the transmitters and/or the receiver to improve radio reception. For more
information on this topic refer to chapter Installation > Mounting location.
Erroneous readings
If the received readings are obviously wrong or intermittent, first check the condition of the sensor, sensor
cable and connection to the transmitter. Check also that the temperature is within the measuring range of
the transmitter. Finally check the sensor and calibration settings of the transmitter.
Troubleshooting tools
Useful information for troubleshooting can be found with MekuWin program from Mon section of the
menu.
Mea
Measured and linearized value of the transmitter.
Sca
Scaled measurement value. Radio transmitter sends this value.
VCJ
Cold junction temperature diode’s voltage as millivolts. Only relevant when sensor is set as thermocouple.
TCJ
Cold junction temperature in degrees Celsius.
Vbatt
This is the measured battery voltage. The nominal voltage of the battery is 1.5 V. When new, the battery
may yield almost 1.6 V. The battery is exhausted when the voltage drops below 0.9 V.

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Specifications
MTR265B
Environmental
Operating temperature -30…+60 °C
Storage temperature -40…+70 °C
Humidity < 95 %RH non-condensing
Protection class IP 65
Case material POM
External dimensions
Height (incl. connectors) 227 mm
Width 29 mm
Depth 31 mm
Power supply
Battery 1.5 V type LR03 (AAA)
alkaline, ”heavy-duty”
Typical battery life time 2 years with 4min trans.int.
6 months with 27s trans.int.
Regulatory information
EMC immunity EN 61326
EMC emissions EN 61326, class B
R&TTE-directive EN 300 220, class 3,
transmitter power class 8
EN 301 489
EN 300 339
EC regulation 37/2005 EN 13485
EN 13486
EN 12830
Radio transmitter
Type Licence free 433.92 MHz
ERC/REC/70-03 sub band f
Frequency band 433.92 MHz ISM band
Power +10 dBm E.R.P. maximum
Open space range up to 500 m
Indoor range 50…100 m typical
Antenna integrated helix
Compatible radio receivers Nokeval MTR, RTR, FTR, DPR
and FT20 series 433.92 MHz
radio receivers.
External temperature sensor measurement
Sensor type Pt, Ni, Cu resistive
temperature sensors and
thermocouple sensors
Cable length < 3 m
Measuring ranges Pt100: -200…+700 °C
and linearity error Ni100: -60…+180 °C
(in parenthesis) Cu: -200…+260 °C
Ohm: 0…10 kΩ
mV: -30…2000mV
TcB: 400…1700 °C (0.3 °C)
TcC: 0…2300 °C (0.5 °C)
TcD: 0…2300 °C (1 °C)
TcE: -100…900 °C (0.2 °C)
TcG: 1000…2300 °C (2 °C)
TcJ: -160…950 °C (1 °C)
TcK: -150…1370 °C (0.5 °C)
TcL: -150…900 °C (0.5 °C)
TcN: 0…1300 °C (0.1 °C)
TcR: 0…1700 °C (0.5 °C)
TcS: 0…1700 °C (0.5 °C)
TcT: -200…400 °C (1 °C)
Accuracy (Pt100 4-wire) 0.05% rdg + 0.2 °C @ 25 °C
Accuracy (mV) 0.05% rdg + 0.01 mV
Accuracy (thermocouples) 0.05% rdg + 0.6 °C + lin. error
+ ambient temp. effect
Thermal drift 0.02 °C/°C ref. 25 °C
Load (mV) >1 MΩ