Nokeval MTR260C User Manual

User Manual

Firmware version V1.5

14.3.2007

MTR260C

TEMPERATURE TRANSMITTER

Nokeval

MTR260C User Manual

DESCRIPTION

MTR260C is a battery powered wireless temperature transmitter that has an internal Pt100 sensor.
It is housed in a compact, water tight, plastic enclosure and comes with a metal wall mounting
bracket that enables easy fastening. MTR260C has an external antenna for a radio coverage
area of up to one kilometer in open space. The wireless concept allows easy implementation,
installation and expansion of a measuring system even in difficult locations and installation sites.
The transmission interval can be programmed from 5 seconds to 5 minutes.

Manufacturer

Nokeval Oy
Yrittäjäkatu 12
FI-37100 Nokia
Finland

Tel: [phone]
Fax: [phone]
Web: www.nokeval.com

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MTR260C User Manual

95 mm

75.5 mm

Ø

4.2

m

m

28.3 mm

28.3 mm

INSTALLING

Installing/replacing the battery

Detach the device from the metal wall mounting bracket and open the case by pulling the cap part
off. Install the battery (ER14250 3.6 V) to the battery slot and close the case. Make sure that the
black sealing ring stays in its place when you close the case.

+

–

ATTENTION! Turn the battery around before use.

When the device is delivered the battery is reversed on
purpose. Install the battery as shown in the picture above.

If the device has been in cold environment wait until the device’s temperature has reached the
ambient temperature before opening the case to prevent condensation in the device.

The battery voltage will not drop before the battery is almost empty, but then the voltage drop is
steep. See the specifications page for more information about battery life time.

Using wall mounting bracket

The wall mounting bracket can be mounted to a wall horizontally or vertically using two screws.
MTR260C transmitter locks into its place when it is slided into the bracket.

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MTR260C User Manual

Transmitter placement

Typical coverage range indoors varies from fifty to one hundred meters depending on the
obstacles between the transmitter and receiver. The best signal level is achieved when there is
a line of sight between the transmitter and receiver. Walls and obstacles, especially closed metal
structures, attenuate the signal and therefore decrease the coverage area. It is recommended to
avoid installing transmitters in such places if possible.

To achieve the best coverage area, place the transmitter so that its antennas are in vertical
position. If necessary, you can slightly bend the antennas. It is recommended to bend the antennas
outwards especially when the device is installed to a metal wall.

Both the wall mounting bracket and the device have the same ID number attached. This helps
placing the transmitter back to its original position if you have temporarily removed the transmitter
from the bracket for calibration or configuration.

Device’s ID number

Indicator lights

The device has a transmit indicator light that flashes every time measurement data is sent.

Transmit indicator light

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MTR260C User Manual

Connection settings

Use Mekuwin program or Nokeval 6790 hand held programmer to configure the device. You can
download Mekuwin from Nokeval’s web site for free.

Communication settings for configuration:
Baud rate 9600
protocol SCL
address 0

Programming connector

Use RS232-POL or POL cable and POL – pin header adaptor to connect the device to PC’s serial
port or Nokeval 6790 hand held programmer. When the programming connector is connected the
device sends measurement data about three times per second. When the configuration connection
is open no measurement data is sent.

Programming connector

Menus

In submenu

Input submenu is reserved for factory settings.

Out submenu

Period

Number of periods between consecutive
transmissions. The minimum value for this
setting is two and maximum value is 127.
One period is approximately 2.7 seconds
(25 °C). The duration of a period depends on
temperature and varies from 1.5 to 3 seconds.
It is not recommended to set the period value
smaller than necessary because it has quite a
significant effect on battery life.

Period Nominal Transmission Interval

2 5 s
11
22 1 min
67 3 min

127 5 min 40 s

5

30 s

MTR260C User Manual

Receiver

Receiver and Receiver and

1 repeater 2 repeaters

Maximum number of transmitters

5

22 11 7

10

43 22 14

20

87 43* 29

30

130 65 43

40

174 87 58

50

217 109 72

60

261 130 87

70

304 152 101

80

348 174 116

90

391 196 130

120

522 261 174

240

1043 522 348

Transmission

Interval (s)

The maximum number of transmitters

The maximum number of radio transmitters in a coverage area is limited by radio standards. The
use of repeaters reduces the maximum number of transmitters because repeaters use the same
frequency channel as transmitters. The following example table shows the allowed maximum
number of MTR260C transmitters in a coverage area.

For example, if you have transmission interval of 20 seconds and one repeater, the maximum
number of transmitters is 43*.

The collision probability of radio data packets increases when the number of transmitters in a
coverage area increases or the transmission interval decreases. The following picture shows how
the collision probability raises as the number of transmitters increases.

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SPECIFICATIONS

Estimated Battery Life Time (25°C)

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

0 10 20 30 40 50 60 70 80 90 100

Transmission Interval (s)

Years

350 mm

95 mm

MTR260C User Manual

Input

Pt100

Range -30…+60 °C
Accuracy +/- 1.0°C

Temperature stabilization time is 10 minutes.

Battery

Model ER14250
Voltage 3.6 V
Chemistry type LiSOCl
chloride)
Size ½AA

(lithium thionyl

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External Dimensions

Transmitter
95 mm x 29 mm x 29 mm

Antenna
175 mm + 175 mm

Weight 65 g
(includes holding bracket)

Radio transmitter

License free 433.92MHz subband f according
to ERC/REC/70-03.

Battery life time will be shorter in extreme
temperature conditions.

Used batteries are hazardous waste. Same
battery model must be used to replace a dead
battery.

Compatible radio receivers

Nokeval MTR, RTR and FTR series radio
receivers.

Environment

Operating temperature -30...+60 °C
Storage temperature -40...+70 °C
Protection class IP67

Coverage Area
Open space up to 1000 m
Indoors 50-100 m (typically)

Regulations

EMC directive

• EMC immunity EN 61326

• EMC emissions EN 61326, class B

R&TTE directive

• EN 300 220 class 3,
Transmitter power class 8 (10 mW)

• EN 301 489

• EN 300 339

Commission regulation (EC) No 37/2005

• EN 13485

• EN 13486

• EN 12830

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MTR260C User Manual

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