Landis+Gyr 2WR5 Operating Instructions

Ultrasonic Heat Meter

Operating instructions

These operating instructions have to be handed over to the end user
The heat meter 2WR5 combines state of the art
microcomputer technology with innovative ultrasonic
metrology avoiding any moving mechanical parts.
This technology is therefore non-wearing and largely
maintenance-free. High accuracy and long-time
stability ensure correct and fair heating cost
accounting.
The quantity of heat output from the heating water
is proportional to the difference in temperature
between the supply and return temperatures and the
volume of heating water having flowed.
The heating water volume is measured by an
ultrasonic pulse that is first sent in the direction of
flow and then against the direction of flow.
With the flow the signal transmission time between
the transmitter and receiver is reduced and against
the flow it is increased.
The volume of heating water and the temperature
difference between the supply and return are then
multiplied and the product is added to the running
total.
The result is the quantity of heat consumed. This
result is recorded and displayed in physical units
kWh / MWh or in MJ / GJ.
2WR5
UH 302-101l
mo tralec
4 rue Lavoisier . ZA Lavoisier . 95223 HERBLAY CEDEX
Tel. : 01.39.97.65.10 / Fax. : 01.39.97.68.48
Demande de prix / e-mail : service-commercial@motralec.com
www.motralec.com

Display

The heat meter display is subdivided into several
levels and may differ from the standard shown
below. The user loop display (level 1) is advanced
cyclically each time the button is pressed briefly.

User loop

Accum. qty of thermal energy
Tariff register, here, e.g. cold
Accumulated volume
Segment test
Error with/without error digit
The tariff displays can vary depending on the tariff
type. The displays shown here are for a combined
heat/cold meter. The valid tariff status is displayed
together with the thermal energy as _ , = or . ≡.
With a pure flow meter the heat and tariff registers
are not displayed.
If button is held pressed for three seconds, the
display switches from the user loop to the service
loops (level 2).

Service loops

Service loop 1
Service loop 2
Service loop 3
One of the service loops is preselected by pressing
the button briefly. By pressing the button for another
3 s the contents of the selected service loop will be
displayed.
Each time the button is pressed briefly the next
information is displayed.
The service loops are exited by holding the button
pressed for 3 s or automatically after 30 minutes.