Operating Mode 6 (Ext Lc Bus); Operating Mode Changeover To Internal Load Controller - Siemens LMV51 Series Basic Documentation

Operating mode 6
(Ext LC bus)
Siemens Building Technologies
HVAC Products
BACS as control with digital predefined load via bus.
The LMV5... system is connected to a BACS via the AZL5... and an external bus inter-
face (e.g. eBus or Modbus).
The BACS contains the controller and transmits the load (manipulated variable) and the
heat demand signal to the LMV5... system.
In this operating mode, the load controller inside the LMV5... is not required.
-Predefined output
-Demand for heat
BMS
Modbus /
e-bus

6.3.1 Operating mode changeover to internal load controller

To improve availability, a potential-free contact at inputs X62.1/ X62.2 can be used to
switch from any of the other operating modes to the internal load controller. In that
case, setpoint W1 applies. For the selected external operating mode, the switch con-
nected to X62.1 / X62.2 is open. For switching over to the internal load controller, the
switch will be closed.
Note:
When switching to operating mode 2 by means of an external contact, parameter
«LC_OptgMode» set by the AZL5... will not be switched over. If one of the external op-
erating modes was selected with the AZL5..., the internal LC parameter will no longer
be offered for making settings. For this reason, to set the internal LC, parameter
«LC_OptgMode» must first be set to «IntLC». Then, the LC operating mode must be
set to the desired external operating mode.
To ensure that controller input X5-03 will not be valued when changing to operating
mode 1 (ExtLC X5-03), the «on / off» controller input at (ExtLC X5-03 Pin 1) should be
deactivated. In operating mode 1 (ExtLC X5-03), the input is nevertheless active. Then,
when changing to the internal load controller, the «on / off» controller input is deacti-
vated.
Parameter:
Input Controller (activated / deactivated)
Basic Documentation LMV5...
6 Temperature or pressure controller (internal load controller LC)
Internal
load controller
AZL5...
Manipulated variable,
demand for heat
Manipulated variable,
demand for heat
CAN module
(basic unit)
Manipulated
Demand
variable
for heat
0...100 %
FARC (BU)
BC (BU)
CAN bus
CC1P7550en
13.08.2004
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