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The OMWT-TEMPRH Wireless
Temperature and Relative Humidity
transmitter is a battery operated
digital temperature and relative
humidity sensor with a micro-processor
controlled 418 MHz FCC
certified radio transmitter. It has an
on board time of day clock that
allows it to spend most of the time
in a low power quiescent state. At
predetermined time intervals the
clock will wake up the onboard
microprocessor. Unique serial
number information digital
temperature and relative humidity
data are read from a semiconductor
digital temperature sensor and a
relative humidity sensor. This
information is combined with a
CRC-16 error check and transmitted
in a very short data packet that
results in a transmitter on time of
only 15 milliseconds. This
architecture allows the OMWT-TEMPRH
to consume very low
energy resulting in a battery life of
up to 2 years.
The electronics are coated with a
conformal rubber material that
provides a moisture barrier against
condensation. Submersion in water
is not recommended. A hole in the
top ABS cover permits a special tool
to be inserted to activate the service
switch. The OMWT-TEMPRH is
shipped with the transmitter turned
off (anytime the device is to be
shipped the transmitter should be
turned off or must be placed in a
shielded container to prevent
interference that might cause
shipping problems). Start the device
by momentarily pushing the service
switch (you will feel the button click).
When the service switch is pushed,
a data transmission occurs
immediately and a special mark is
introduced in the ID field of the
transmitted data packet to indicate
which device is in service or
installation.The service switch is
also used to put the device in a
quiescent mode (no transmissions
and very low power consumption).
This is the state the device is in
when you receive it. Push and hold
the service switch for 10 seconds or
more to enter this powered down
state.
Using the OMWT Series Windows
software incoming data being
received from OMWT Series
Wireless Transmitters can be
viewed in a real-time or historical
time-base chart or numerical view.
High/low alarms can also be set for
each transmitter signal with either a
visual or audible alarm indication on
the PC. Data can also be logged to
disk at a user-specified rate in a text
file format that can be opened up
into Microsoft Excel. The OMWT
Series Windows software also
includes a DDE Server that can
interface the data being received
from OMWT Series Wireless
Transmitters to other Windows
software packages.
Specifications
Transmission Frequency:
418 MHz *Transmission Range:
up to 180 m (600') depending on environmental conditions Transmission Rate: 10 to 17
seconds random Operating Temperature:
-40 to 70°C (-40 to 158°F) Storage Temperature:
-40 to 70°C (-40 to 158°F) Temperature Accuracy:
±0.5°C from -10 to 85°C
(-18 to 185°F) Humidity: 0 to 100% RH
non-condensing Humidity Accuracy:
±5% full scale at 25°C Humidity Response Time:
15 sec in slowly moving air at 25°C Battery: 3.6V lithium battery included Battery Life with Transmissions:
2 years Shelf Life with Battery Installed:
5 years in quiescent mode FCC Certified: FCC ID: M5ZTHL Dimensions:
38 H x 53 W x 15 mm D
(1.5 x 2.1 x 0.6") Weight: 43 g (1.5 oz)
注: Each unit comes complete with operator’s manual.
