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Building Technologies    CC1N7101en 
HVAC Products    27.11.2008 
Technical data (cont´d) 
 
 
 
 
At mains voltage  
UN = AC 120 V ¹)  UN = AC 230 V ¹) 
Detector voltage between ionization probe and ground  
(AC voltmeter Ri ≥ 10 MΩ) 
AC 50...120 V  AC 115...230 V 
Switching threshold (limit values): 
Switching on (flame on) (DC ammeter Ri ≤ 5 kΩ) 
Switching off (flame off) (DC ammeter Ri ≤ 5 kΩ) 
 
≥ DC 1.5µA 
≤ DC 0.5µA 
 
≥ DC 1.5µA 
≤ DC 0.5µA 
Detector current required for reliable operation 
≥ DC 3µA  ≥ DC 3µA 
Switching threshold in the event of poor flame during operation 
(LED flashes green) 
Approx. DC 5µA  Approx. DC 5µA 
Short-circuit current between ionization probe and ground 
(AC ammeter Ri ≤ 5 kΩ) 
Max. AC 50...150µA  Max. AC 100...300µA 
 
¹) For applications outside the European Community, operation at mains voltage  
   AC 120 V / AC 230 V ±10% is    ensured 
 
With the same quality of flame, the detector current with the LME… may be other 
than with the LMG… / LGB… 
 
Flame supervision with ionization is accomplished by making use of the conductivity 
and rectifying effect of the flame. The flame signal amplifier only responds to the DC 
current component of the flame signal. A short-circuit between ionization probe and 
ground causes the burner to initiate lockout. 
 
LME...
1
7101v01/0804
M
C
+
+
-
ION
 
Legend 
 
C  Electrolytic capacitor 100...470µF; DC 10...25 V 
ION Ionization probe 
M  Microammeter, Ri max. 5000Ω
 
 
For detector currents, refer to « Technical data ». 
 
Flame supervision 
with ionization probe 
Note 
Measuring circuit