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PFU 780 · Edition 02.12l
9
STW
L1
>750 °C
µC
PFU 780..D
18a
26a
DI
22a
µC
PFU 780..D
18a
26a
DI
22a
Application
1 .1 .4 PFU 780 . .D: High
temperature equipment
The flame is controlled indirectly on
the basis of the temperature. During
the start-up process, as long as the
wall temperature is below auto igni-
tion temperature the flame must be
controlled by conventional meth-
ods. When the working temperature
has exceeded 750°C, the safety
temperature monitor (STW) takes
over the indirect flame control.