32/69
Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
9 Assignment of terminals and description of inputs / outputs (I / O)
15.10.2002
9.2 Description of the inputs / outputs
Terminal
Input / output
Voltage
Description
B2
I
DC 0...10 V
Potentiometer (wiper ) from auxiliary actuator (AUX1(1))
B3
I
DC 0...10 V
Potentiometer (wiper) from auxiliary actuator (AUX1(2))
B4
I
DC 0...10 V
Potentiometer (wiper) from auxiliary actuator (AUX2)
F1
I
AC 230 V
Fuel selection: Fel 1
F2
I
AC 230 V
Fuel selection: Fuel 2
L
I
AC 230 V
Live for internal power supply, actuator outputs and «Q1»
N
I
Neutral conductor for internal power supply, reference potential for the mains
voltage inputs (all N-terminal are
internally
interconnected)
M
Reference potential for all low voltage inputs / outputs and for the screening
(all M-terminals are
internally
interconnected)
Q1
O
AC 230 V
Acknowledge signal: Indicates to the burner control when certain actuator posi-
tions are reached
Q2
I
AC 230 V
Signal from burner control: First fuel valve on / off
Q3
I
AC 230 V
Signal from burner control: Fan on / off
Q4 – Q5 / H
O
potential free Readiness contact / control loop: Indicates operational readiness of the
RVW26...
TxD
O
Interface for the RVW25.000B27
RxD
I
Interface for the RVW25.000B27
GND
Reference potential for the interface
U1
I
DC 0...10 V
Signal input for analog burner output control
U3
I
DC 0...10 V
Signal input for predefined speed from the RVW25...
U10
O
DC 10 V
Power supply for potentiometers (all «U10» terminals are
internally
intercon-
nected)
X1
O
DC 0...10 V
Burner load signal
X2
I
DC 0...10 V
Correcting variable signal from O
2
trim control of the RPO25...
X3
O
DC 0...10 V
Predefined speed for the variable speed drive
Y3
O
AC 230 V
Positioning signal (open) for actuator «AUX1»
Y4
O
AC 230 V
Positioning signal (close) for actuator «AUX1»
Y5
O
AC 230 V
Positioning signal (open) for actuator «AUX2»
Y6
O
AC 230 V
Positioning signal (close) for actuator «AUX2»
Y8
O
AC 230 V
Positioning signal for the RVW25..: valve «ON / OFF»
Y10
I
AC 230 V
Signal for prepurging from the burner control
Y20
I
AC 230 V
Signal for ignition position and «CLOSE» position from the burner control
+5 V
O
DC 5 V
Auxiliary voltage, max. 1 mA