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Siemens Building Technologies
Basic Documentation LMV5...
CC1P7550en
HVAC Products
4 Burner control
13.08.2004
This input serves for the connection of an external controller with contact outputs. The
input is only active when configured as «External load controller».
Parameter:
LC_OptgMode (ExtLC X5-03)
2 operation modes are possible. The one active depends on the parameterization of the
fuel / air ratio control system.
a) Parameter:
Operation Mode (Two-stage / Three-stage)
Multistage operation can be accomplished by using additional thermostats / pressure
switches.
Input « » activates stage 2.
Input « » and input « » activate stage 3.
b) Parameter:
Operation Mode (Modulating)
The burner’s output can be increased or decreased by means of a 3-position step con-
troller output with 2 relays.
«
▲
» increases the output
«
▼
» decreases the output
If none of the 2 inputs is active, the burner’s output is maintained at a constant level.
The shortest permissible positioning step is about 100 ms.
An air pressure switch can be connected to these terminals. Air pressure is anticipated
after the fan has been switched on. If there is no pressure signal, safety shutdown will
occur in any case. The input can be deactivated.
Parameter:
AirPressureTest
(activated / deactivated)
2 inputs (ON / OFF or
STAGE2 / STAGE3)
(
2
3
)
X5–03
Air pressure switch
(APS) X3–02
2
2
3