5511-185 GB-DE
-DK/03.2005/R
ev
. E1
6
It is most easily measured from a M-Bus
Slave mounted in a MULTICAL
®
bracket
as the top part of the M-Bus Master must
be mounted.
When reading via a PC the light emitting
diode marked REQUEST will be lighted
briefly, when you request data and the
light emitting diode marked DATA will
be lighted when a M-Bus Slave replies.
The M-Bus Master with display shows:
Initialization of the M-Bus network takes
approx. 3 minutes, depending on the
number of M-Bus Slaves. The LED marked
REQUEST blinks constantly and when a
M-Bus Slave answers, the LED marked
DATA blinks.
After initialization three dots appear:
Press the left button once, an address
appears, press the right button once,
a DAT appears, after 10 to 40
seconds data is shown. The system is
in order.
5. Installation of M-Bus system
M-Bus Master and M-Bus Slaves
are connected on a 2-wire bus. All
M-Bus Slaves must be connected in
parallel on the bus.
Supply of M-Bus Slaves and communi-
cation take place through the same two
conductors. As the M-Bus Master has
two parallel sets of terminals (24–25),
two physical sequences can be emitted
from the M-Bus Master. Two sets of wires
can be mounted in the M-Bus Slave’s
terminals, bus in/ bus out. It is thereby
possible to make a loop in MULTICAL
®
’s
bracket.
The recommended conductor cross-
section is 0.5 mm
2
or 0.8 mm
2
. Subject
to an even distribution of M-Bus Slaves
in the network, the max. cable length at
0.5 mm
2
is approx. 1000 m, and at 0.8
mm
2
approx. 1800 m. The voltage mea-
sured at the remotest M-Bus Slave must
not be lower than 12 VDC when the M-Bus
Slave sends data to the M-Bus Master.
A screened cable is not required. We
recommend that the M-Bus cable is drawn
at a fair distance from power cables.
