JUMO 707060 Wtrans B - Programmable Head Transmitter with Radio Transmission Operating Manual - Manual (Page 6)

1 Introduction
6
1.2 Description
The Wtrans B head transmitter with wireless data transmission is used in connection with a
Wtrans receiver unit for stationary or mobile temperature measuring with RTD temperature
probes or thermocouples. Alternatively, resistors with an ohmic-value of up to 10 k
Ω , voltages
up to 50 mV, and currents up to 20 mA that use an external shunt are measurable. Customer-
specific linearizations are possible.
The measured values are transmitted wirelessly to the receiver of the Wtrans measuring sys-
tem. These values are shown on the receiver's LCD display and are digitally available on the
RS485-interface or as analog output(s). Optionally, different alarm types can be indicated with
the two relay outputs.
This head transmitter is designed for industrial applications – it is made up of the transmitter
with an integrated transmission unit and an antenna-battery case. The transmitter is designed
to be installed into type B terminal heads and works in an ambient temperature range from -30
to 85 °C. It is possible to install the transmitter into customer-specific terminal heads. The an-
tenna-battery case is connected to the terminal head through a screw connection (M20 × 1.5).
The transmission frequency of the Wtrans measuring system is 868.4 MHz. This frequency is
unaffected for the most part by external interferences and it allows for transmissions even in a
rough industrial environment. When using the antenna wall-holder with the 3 m antenna line for
the receiver then the maximum open-air range is 300 m.
A 3.6 V, 2.2 Ah (size AA) lithium battery is used as a power supply for the transmitter. For the
easy configuration and parameterization of the head transmitter and the Wtrans receiver on a
PC an optional setup program is available. Additionally, measured values can be recorded on
the PC with the online-chart function.
1.3 Block diagram
Transmission unit
Transmission
frequency
868.4 MHz
Head
transmitter
Power supply
Lithium battery
3.6 V, 2.2 Ah
Interface
Setup
Analog input
+
-
RTD
temperature probe
Thermocouple
Resistance /
Potentiometer
Voltage
Resistance transmitter