User Manual

19/22
Building Technologies CC1N7546en
13.04.2018
Technical Data (cont´d)
No-load voltage at QRB1/QRB3 terminal
(X10–05 terminal 3)
Approx. DC 5 V
Max. perm. length of QRB1/QRB3
detector cable (laid separately)
3 m (wire – wire 100 pF/m)
Β
Note
A detector resistance of RF <500 ς is identified as a short-circuit and leads to safety
shutdown in operation as if the flame had been lost.
For this reason, before considering the use of a highly sensitive photoresistive detector
(QRB1B or QRB3S), it should be checked whether this type of flame detector is indeed
required! Increased line capacitance between QRB1/QRB3 connection and mains live
wire L has an adverse effect on the sensitivity and increases the risk of damaged flame
detectors due to overvoltage. Always run detector cables separately!
Threshold values when flame is supervised by QRB1/QRB3:
Start prevention (extraneous light)
with RQRB
<400 kς
Intensity of flame ≥10%
Operation with RQRB <230 kς
Intensity of flame >16%
Short-circuit detection with RQRB <0.5 kς
0,1 1 10 100 1000
B
i
l
d
4
6
2
e
n
/
0
7
1
8
A flame detector resistance of RF <500 Ω is identified as a short-circuit and leads to
safety shutdown in operation, like in the case of loss of flame.
Flame supervision with
QRB1/QRB3