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Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
5 Description of functions
15.10.2002
With dual-fuel burners, 2 actuating devices (only «AUX1») can be controlled
·
either jointly with 1 actuator, or
·
each with 1 actuator
Which of the 2 choices is used depends on the type of burner construction.
The selected mode must be set on the RVW26… (refer to «Programming»).
Version 1
Version 2
(1 actuator)
The potentiometer's feedback signal is fed
to terminal «B2».
The auxiliary actuator is automatically po-
sitioned according to the «AUX1(1)» or
«AUX1(2)» curve.
(2 actuators)
The potentiometers' feedback signals are
fed to terminals «B2» and «B3».
Both actuators can be switched externally
with an auxiliary contact of the fuel selec-
tor.
The inactive actuator should be driven to
the end switch position «Fully closed».
B2
RVW26
AUX1
Y4
Y3
M
P
Fuel1
Fuel2
RVW26
L
78731y01/0601
B3
Y3
Y4
M
M
B2
P
P
AUX1(1)
AUX1(2)
Fig. 13
Connection of the auxiliary actuators
Applications with 1 or
2 auxiliary actuators
«AUX1»
Connection of the
auxiliary actuators