Siemens Building Technologies
Basic Documentation RVL470
CE1P2522E / 30.03.2000
Landis & Staefa Division
Function block "Service functions and general settings"
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13.5.4. Bus power supply
In interconnected plants comprising a maximum of 16 controllers, the bus power supply
may be decentralized, that is, power may be supplied via each connected device.
On each connected device it is necessary to set whether the data bus is powered cen-
trally or decentrally by the various controllers.
With the RVL470, this setting is made on operating line 179. The display shows the cur-
rent setting as SET and the current bus power supply status as ACTUAL.
Display
Bus power supply
SET
0
Bus power supply is central (no power supply via controller)
SET
A
Bus power supply is decentral via the controller
ACTUAL
0
Presently no bus power supply available
ACTUAL
1
Bus power supply presently available
The word BUS appears on the display only when a bus address is valid and bus power
supply is available. This means the display indicates whether or not data traffic via the
data bus is possible.
13.5.5. Bus loading characteristic
The bus loading characteristic E for the LPB of the RVL470 is 6. The total of all E
figures of the devices connected to the same bus may not exceed 300.
