Siemens AGM60.4A9 - Flame Supervision Technical Data; Ionization Probe Flame Detection

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Smart Infrastructure CC1N7544en
21.05.2021
Technical Data (cont´d)
No-load voltage at ION terminal
(X10
–
05 pin 2)
Approx. UMains
Caution!
The ionization probe must be protected against electric shock hazard
(electric shock hazard)!
Short
-
circuit current
Max. AC 1 mA
Required detector current Min. DC 2.3 µA,
flame display approx. 30 %
When the more sensitive flame
supervision is activated, the required
detector current is halved (refer to chapter
Flame detection sensitivity in the Basic
Documentation P7544).
Possible detector current Max. DC 12…30 µA, flame display
a
p
prox. 100 %
Max. perm. length of detector cable
(laid sep
a
rately)
3 m (wire–ground 100 pF/m)
Warning!
Simultaneous operation of QRA and ionization probe is not permitted!

Note
The higher the detector cable’s capacitance (cable length), the more voltage at the
ionization probe, and thus the detector current, drops. Long cable lengths plus very
highly resistive flames might necessitate low-capacitance detector cables (e.g. ignition
cable). In spite of technical measures taken in the circuitry aimed at compensating
potential adverse effects of the ignition spark on the ionization current, it must be
made certain that the minimum detector current required will already be reached
during the ignition phase. If this is not the case, the connections on the primary side of
the ignition tran
s
former must be changed and / or the electrodes relocated.
Threshold values when flame is supervised by an ionization probe:
-
Start prevention (extraneous light)
Flame intensity (parameter 954)
≥
18 %
-
Operation
Flame intensity (parameter 954) >24 %
Flame supervision with
ionization probe