18/19
Building Technologies
CC1N7461en
21.08.2018
Connection examples for modulating burner control including checked air damper control
Modulating burners designed for the continuous adjustment of the burner‘s output require a temperature or pressure
control system, in addition to the standard burner control equipment, for example:
Modulating controller
RWF5
Temperature or pressure sensor with integrated setpoint adjuster
Q...
Actuator for control of the air damper and the fuel throughput (ratio control)
SQ...
Auxiliary relay
d1
Operating switch
BS
Control valve or similar for adjustment of the amount of fuel
RV
M1
c1
e1
M
P (R)
M2
M
c2
e2
H
SB
N (Mp)
ION
LF
+
EK2
L2
c
1/c
2
LP
P
T
W
T
R
P
GP
e1
c1
c1
I
II III
IV
d1
LK
BS
a
11
1
M
N
2
z
c1
SQ...
RV
Q...
e2
c2
Z
GV1
d1
1 2 13 14 15 16 12 19 18
8 9
4
3
20 22
21
10
11
17 6
5
7
LFE1
7461a13/0207
L1
N
When using UV flame detector QRA..., terminal 13 must be connected to earth.
Operating switch BS
I
Nominal load
II
Stop
III
Part load
IV
Automatic control
(17)
3
4
8
9
18
19
e
M
~
M
c
max. 5A
LP
P
R
T
W
T
0,1A
N (Mp)
7461a15/1196
The air pressure is constantly monitored from burner start to
controlled shutdown. If the set minimum air pressure is not
reached 10 seconds * after the start of prepurging (7
seconds ** with the program with pre- and postpurging), or
the air pressure is lost again any time thereafter, the burner
control will initiate lockout. If the air pressure switch «LP» is
connected as shown in the adjacent diagram, the switch is
also automatically tested for correct functioning prior to each
start. If the contact’s position is not correct, startup will be
prevented.
* (5 seconds with the LFE1.1...)
** (3.5 seconds with the LFE1.1...)
ION
M
-
+
14
13
LFE1...
7461a16/0207
Legend
ION
Ionization probe
M
Microammeter
Attention!
Ignition can have an impact on the ionization current.
(Possible remedy: interchange the ignition transformer’s primary connections)
Air pressure switch «LP»
Measuring circuit for ionization current
