Unigas R91, Installation Manual

Page: 37 / 120

PART IV: MAINTENANCE
37
5.5
Matching the combustion heads and the control boxes
The combustion head is made of four heads: one is provided with a detection electrode connected to the Siemens LMV control box ;
the other three heads are provided with electrodes connected to the Krom-Schroeder IFW15 flame detectors .
5.6 Checking the detection current (natural gas)
To check the detection signal follow the scheme in the picture below. If the signal is less than the value indicated, check the position of
the detection electrode or detector, the electrical contacts and, if necessary, replace the electrode or the detector.
Device
Flame detector Minimum detection signal
Siemens LMV2x/3x
Ionization probe 4 µA (values on display: 30%)
C
B
D
A
A
B
C
D
Protective earth PE
Ionization probe (ION)
QRB.../ QRC... signal voltage
QRB... GND
1
2
3
4
5
L
X10-05
Detection electrode
R91, R92, R93, R515
Ignition electrode
Earth electrode