Endress+Hauser Liquiphant S FDL60, Functional Safety Manual

Page: 13 / 24

Liquiphant S, Nivotester
Hauser 13
SD175en05
Flow diagram of function test
1) lit: fault in sensor
2) lit: fault in data transfer
3) lit: fault in Nivotester
4) flashing: permanent self-monitoring
5) lit: level below maximum
6) lit: level alarm
7) "test" key
8) lit: fault; unlit: normal operation
!
Note!
If one of the test criteria from the test sequences described above is not fulfilled, the device may no longer be
used as part of a safety instrumented system.
The purpose of proof-testing is to detect random device failures. The impact of systematic errors on the safety
function is not covered by this test and must be assessed separately.
Systematic errors can be caused, for example, by process material properties, operating conditions, buildup or
corrosion.
z 26
d 26
b 28
d 18
b 20 d 18
b 20
FTL670
s
z 26
d 26
b 28
s
*
*
0 1 2 3 4 5 6 7 8
1)
6)
2)
5)
3)
8)
7)
4)
yellow
yellow
yellow
yellow
green
red
red
Test key pressed
Level alarm relay de-energised
Fault alarm relay de-energised
energised
Time
energised
Test key released