User Manual

Use
The 2WR6.. heat and cooling energy meter is used to acquire energy consumption
in a physically correct way. The device consists of a flow measuring section, 2
ready connected temperature sensors and a processor to calculate the energy
consumption based on the flow rate and the temperature differential. The 2WR6..
is of compact design and therefore ideally suited for use in apartments. It is
available for heat or cooling energy.
Temperature sensors and battery of the 2WR6.. cannot be replaced.
The product is not suited for use in systems operating on water-glycol mixtures.
Functions
The heat meter consists of processor, flow measuring section and 2 temperature
sensors (return temperature sensor is always integrated in the measuring tube).
- Pt500, type DS M10x1 mm, direct immersion, immersion length 27.5 mm
- Pt500, type PS Ø 5.2x45 mm, direct immersion or for protection pocket
The processor is alternatively powered by …
- a battery with a life of 11 years
- external power supply AC/DC 24 V
The volume flow is acquired based on the ultrasonic measuring principle, free from
wear due to the use of non-moving parts.
The amount of energy supplied by the medium to the consumer during a certain
period of time is proportional to the temperature differential of flow and return and
the volume flow passing through the meter.
The water volume is acquired in the measuring tube by ultrasonic pulses trans-
mitted in the direction of flow and against the direction of flow. Downstream, the
time required by the pulses to travel from the transmitter to the receiver is reduced,
upstream it is increased. The water volume is then calculated based on these
measured values.
The flow and return temperatures are acquired by platinum sensors.
The water volume and the difference in temperature between flow and return are
multiplied and its product is integrated. The result, which is the consumed quantity
of thermal or cooling energy, is recorded and displayed in the physical unit
kWh/MWh or MJ/GJ, the volume in m
3
.
A standard processor is used for all flow rate values with identical operation and an
integrated service unit.
The heat meter is equipped with an optical communication interface, enabling the
device to be read and parameterized on site with the help of the WZR-OP-USP
optical read head and the UltraAssist software.
To open the meter, the calibration seal on the front of the 2WR6.. must be
destroyed.
The meter performs constantly self-diagnostics, allowing it to detect a number of
mounting or device errors and to display them.
Restrictions
Basic design
Ultrasonic measuring
principle
Processor
Optical communication
interface
Manipulations
Self-diagnostics
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Siemens Ultrasonic heat and cooling energy meters 2WR6.. CE2N5378en
Building Technologies 2014-04-04