Endress+Hauser Deltabar S PMD75 - Page 12

Deltabar S
12 Endress+Hauser
A0022897
AHI-Alarm ≥ 21 mA
B Error range ± 1%
CLO-Alarm ≤ 3.6 mA
Dangerous undetected failures in this scenario
An incorrect output signal that deviates from the real measured value by more than 1%, but is still in
the 4-20 mA range, is considered a dangerous, undetected failure.
Safety related
error
Explanation Implications for the
safety-related output
signal
Implications for
measuring uncertainty
(position, see Fig.  ä 12)
No device error Safe: SD
No error
None 1 Is within the specification
(see TI, BA, ...)
λ
SD
Safe detected:
Safe failure which can be
detected
Causes the output signal to
signal the failsafe mode
 ä 13
3 No implications
λ
SU
Safe undetected:
Safe failure which cannot be
detected
Is within the defined
error range
2 May be outside specifica-
tions
λ
DD
Dangerous detected:
Dangerous failure which
can be detected
(Diagnostic within the
device)
Causes the output signal to
signal the failsafe mode
 ä 13
3 No implications
λ
DU
Dangerous undetected:
Dangerous failure which-
cannot be detected
May be outside the defined
error range
4 May be outside the defined
error range
I [mA]
B
C
A
t
1
2
4
3
3