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BCU 580 · Edition 11.15l
60
Parameters
10 .2 .3 High temperature operation
Parameter 06
Operation of firing systems at temperatures above
750°C
The BCU..D1 and BCU..D2 have a fail-safe input with
the function “High temperature operation”. If firing sys-
tems are operated above 750°C, the system is consid-
ered to be an item of high temperature equipment (see
EN 746-2). Here, flame control must be in operation
until the furnace wall temperature has exceeded 750°C.
Below 750°C, the flame is monitored by conventional
means (UV sensor or ionization electrode). In High tem-
perature mode (> 750°C), the flame may be controlled
via the temperature using a safety temperature moni-
tor (STM) in order to increase the system’s availability.
This means that no incorrect flame signals, e.g. signals
from a UV sensor which interprets reflected UV radia-
tion as extraneous signals, may lead to faults.
FCU 500..H1
M
HT
18
HT
HT
BCU 580..D
49
5
8
µC
BCU 580..D
49
5
8
µC
5-8
STM
When the HT input is activated (terminal 49), the burner
control unit reverts to High temperature mode, i.e.:
the
BCU operates without evaluation of the flame signal .
The safety function of the device-internal flame con-
trol system is deactivated .
In High temperature mode, the gas valves are opened
and the burners are started as usual without monitor-
ing the presence of a flame.
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