34
7
Instructions on Commissioning and Maintenance
7.2.5
Switch-off test - check the correct setting
WARNING!
Simulate a flame rupture or flame extinction by shunting off the fuel supply to the burner to be
monitored by the flame scanner. Check that the signal for shutting-off the safety valve is trig-
gered off within the period of T
S
< 1 s (on safety period ’Operation’ at t
V
Off = 1 s) after extinc-
tion of the flame.
WARNING!
For the IR compact flame scanners of the F200K1(2) IR-1 and/or F200K1(2) IR-2 types, take
into account the radiation effects characteristic of the combustion chamber. Consequently,
switch-off tests should be carried out when the boiler has reached operating temperature. In
particular, make sure that the sensitivity of the compact flame scanner is increased only to
such a value required to safely and reliably monitor the flame throughout the operating range
of the burner.
7.2.6
Fault on Flame Detection
Check this function according to chapter
7.2.6.1 1. Interference
Generally, interference becomes apparent by the fact that the intensity indicator of the device
may indicate 100 %, but the green LED (’Flame in’) does not light up. Or, the green LED lights
up for a moment, but then it does not change its intensity according to the cycle rhythm and
goes out again. This is a cycle synchronisation fault (signal in both evaluation channel present
at the same time). This may chiefly be due to the interference emission of the ignition trans-
former during ignition.
–
Check the shielding and FPE for proper connection to the F200K
–
Carry out a proper grounding of the ignition transformer
–
Check the cables for laying and if required untangle / separate them spatially
7.2.6.2 2. Exceeding the permissible ambient temperature
Make sure that the maximum allowable ambient temperature of 60 °C/140 °F is not exceeded
at the installation site. In case where the temperature is expected to exceed the limit, take ap-
propriate cooling measures (e.g. cooling air enclosure FS 50, FS 51or FS 56) refer to chapter
10.3.6 Cooling Air Housing with Ball-and-Socket Joint FS51
able, Demountable, with Cooling Air Housing)
. Make sure that the flame detector casing does
not heat up beyond this temperature value due to the impact of the heat radiated by the boiler.
Overheating will result in a sensitivity loss in the first line, or will cause damage to the sensor
elements and with it may result in a total failure of the system.
’Red’ LED
lights
’Green’ LED
dark
