Endress+Hauser PROline 93 II2G Serie Bedienungsanleitung Seite 65

PROline Prosonic Flow 93 FOUNDATION Fieldbus
Endress+Hauser
Intrinsically safe equipment
Prosonic Flow 93
Total capacitance
C = 115.6 nF
eff.
Total inductance
= 423.1 µ H
L
eff.
Tab. 6: Safety considerations (example)
If, in the example examined, the condition L
intrinsic safety with respect to the electrical parameters has a positive result. In this
example, however, the condition was not met since the bus line selected is too long.
Possible solutions:
1. Reduce the main line by 175 m to 405 m (this can be achieved by installing the bar-
rier in the immediate vicinity of Explosion Zone 1, for example).
2. Check under what conditions the manufacturer of the safety barrier or segment con-
nector allows the use of the L/R ratio for technical safety considerations.
Since all the users are permissible for explosion group IIC and the corresponding
parameters have been taken into consideration, the bus segment can be used for gases
in explosion group IIC.
The permissible ambient temperature may be considered either individually for each
device at the respective place of installation, or specified uniformly for the bus segment
as a whole. In the latter case the lowest value of the ambient temperature applies.
Required temperature class
T6
Condition Associated equipment
MTL 5053
< perm. capacitance for IIC
C = 165 nF
o
< perm. inductance for IIC
= 320 µ H
L
o
< L is met, then the demonstration of
eff. o
Intrinsically safe equipment
Cerabar S
Prosonic Flow 93


Condition met?
Yes

No
Maximum ambient temperature
40 °C
50 °C
(at 80 °C medium temperature)
27