8
E
.
1
3
.1
1
.0
6
•
G
.
2
1
.0
9
.1
1
17 Adjustment of the ignition electrodes
The ignition electrodes are preset at the factory.
18 Flame control with Ionisation monitor
In the presence of an alternating-current voltage between burner and ionisation rod, the rectifying effect of
the flame causes a direct current to flow. This ionisation current is the flame signal and is amplified before
being output to the control box. A flame cannot be simulated, because the rectifying effect collapses if there
is a short-circuit between sensor electrode and burner.
Measuring ionisation current
The ionisation current must be measured during burner start-up and maintenance or after a fault indication
in the control box. Disconnect the plug of the ionisation cable and connect the ionisation
measuring cable.
Perform measurement straight after the post-ignition time during the safety time period !
The ionisation current must be at least 1.5 µA. Currents lower than 1.5 µA cause unstable operation or shut-
down. If the current is too low clean the ionisation rod and the inside of the burner tube. It may be necessary
to correct the shape of the ionisation rod. If the ionisation rod is defective, replace the electrode. Reverse
the polarity of the ignition transformer, if necessary. Check the cables for moisture formation and dry if ne-
cessary.
19 Adjustment of the burner head
Set the position of the burner head according to bur-
ner output in accordance with the table on page 16ff.
2,5 - 3 mm
MG1/MG2-LN
3-4
(80)
2
Abstand
Keramikkörper
Keramikkörper
Zündelektrodenhalter
Stauscheibe
Richtrohr
Summary of Contents for MGN 1350 M3D DLU
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