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PFU 780 · Edition 02.12l
6
VR..L
VAG
SPS
PLC
CPE
DI
L1, N, PE
P
2
1
t
1
2
ϑ
1
ϑ
2
A
P
DI
UV
02–04
02–04 06–08
06–08
VBY
PFU 780
10e
2c
4c
18a
26e
10c
22e
22a
28c
16c
18e
6a
6e
2e
4e
14a
30e
10a
TZI
2
1
ϑ
1
ϑ
2
µC
Application
1 .1 Examples of application
1 .1 .1 Stage-controlled main burner
with alternating pilot burner
Control: Main burner ON/OFF.
The main burner can be started with
reduced capacity after the operat-
ing signal from the pilot burner has
been detected. The pilot burner is
switched off automatically after the
main burner has started up. When
the main burner is switched off, the
pilot burner automatically switches
on again.
A UV sensor monitors the flame sig-
nal from pilot and main burners. UV
sensor UVD 1 is used for continu-
ous operation, UV sensor UVS for
intermittent operation.