safetec
Fault Finding Instructions SDS26
16.06.09
Seite 5 von 13
Table 1a and 1b
•
If the measured voltages are correct, but fault indication is still present, the detector
interface module must be exchanged.
•
If the measured voltages are not correct compared with table 1, disconnect the
wires at the terminal nos. 33/34 at the detector interface module. Measure the
resistance between the disconnected wires and compare with the following table:
Situation:
Airflow is present at the
following Line Nos.:
Resistance
[
Ω
]
Resistor-PCB at terminal
nos. 47/48
(without Zener Barrier)
[
Ω
]
1, 2 and 3
1044
784
2 and 3
1174
914
1 and 3
1357
1097
3 1631
1371
1 and 2
2087
1827
2 3001
2741
1 5741
5481
No airflow
∞
∞
Values for line nos. 4 - 6 are corresponding
Table 2
•
If the measured values are not correct compared to table 2, disconnect the wires of
the zener barrier and measure the resistance of the zener barrier between terminal
nos. 4/5 and terminals nos. 1/8 ( 130 Ohm each path ).
•
If the measured values are not correct, the zener barrier is defect.
•
If the measured values are correct, the resistor - PCB must be defect. For
verification measure the resistance of the resistor - PCB betweeen terminal nos.
47/48 and compare with table 2, column no.3.
