6 safety manual, Table 11: achievable pl – JUMO 14597 safetyM STB/STW Ex - Safety Temperature Limiter and Safety Temperature Monitor Operating Manual User Manual
Page 57
6 Safety Manual
51
Important information:
Variants 1 to 4 were evaluated with JUMO probes according to data sheets 901006 and 902006. For variant 5 no sensor sys-
tem was included (only the JUMO safety
M STB/STW Ex). In this case, the plant operator selects the sensor system. For this
reason, the plant operator is responsible for evaluating the achievable PL.
Table 11: Achievable PL
Variant
Connected sensors
Sensor sys-
tem architec-
ture
Logic
ar-
chitecture
Achievable PL
1
1x Pt100 2-wire circuit
1oo1
1oo2D
PLd
1a
2x Pt100/1000 2-wire circuit
1oo2
1oo2D
PLe
2
2x Pt100/1000 3-wire circuit
1oo2
1oo2D
PLe
3
2x thermocouple
1oo2
1oo2D
PLe
4
1x Pt100/1000 2-wire and 3-
wire circuit
1x thermocouple
1oo2
1oo2D
PLe
5
STB/STW 701155 without
sensor system 1oo2D archi-
tecture
No probe or use of 4 to 20 mA
This means the sensor is not
taken into account in the cal-
culation.
Sensors con-
nected by the
plant operator
Architecture
acc. to con-
nection 1oo1
or 1oo2
1oo2D
PL of the used sen-
sor
MTFF
d
= 100 years
Max. achievable PL of
the system with 1oo1
sensor system architec-
ture
DC
701155
≥
90 %
Max. achievable PL of
the system with 1oo2
sensor system architec-
ture
DC
701155
≥
90 %
PLb
PLd
PLe
PLc
PLd
PLe
PLd
PLd
PLe
PLe
PLe
PLe