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Siemens Building Technologies
Basic Documentation LMU54... / LMU64...
CC1P7494en
HVAC Products
5 Clip-in module OCI420... for communication via LPB
07.11.2002
In an interconnected system consisting of LMU… and ALBATROS controllers, only one
common outside temperature sensor is required. This sensor can be connected to any
of the units and then passes its signal to all bus users.
It is also possible to connect outside sensors to several units (buildings using several
outside sensors).
In that case, units that do not have their own outside sensor do not handle all sensor
values they receive but only adopt the outside temperature signal delivered by the unit
with the next lower address.
This means that the address numbers must be assigned such that the unit with no
sensor follows with its number the unit whose signal it has to adopt.
If a unit
cannot
adopt the value of a unit with a lower address number, it will adopt the
measured value of the unit with a sensor that has the highest address number.
Units with a local outside sensor are excluded from this rule. They do not give
consideration to external outside temperature signals.
When interconnecting several LPB-compatible units, address assignment to every
component is mandatory.
The address of a user is like a postal address and may occur in the system only once to
ensure troublefree communication.
A basic distinction is made between device address and segment address.
The device address shall be assigned from 1 to 16 in consecutive order in accordance
with the connected units. The user with device address 1 is the master which should
exist in every segment.
For heating circuit extensions with or without external DHW heating, the device address
of the LMU... is to be set to 1 (master)!
In the case of cascade applications, the value of the device address must be greater
than 1!
The segment address enables the system to be subdivided into several segments.
Units located at the same place of application can be combined in one segment .
The segment address has a setting range from 0 to 14 and must be set to 0 for the
LMU..., independent of the type of application!
Outside sensor, outside
temperature sensor
Assignment of address
numbers
Setting the LPB device
and segment address
Device address
Segment address
