Calculation Of Total Deviation (According To Din 16086) - Vega VEGABAR 66 Operating Instructions Manual

Error messages via the
display and adjustment
module
Total deviation
Example
VEGABAR 66 • Foundation Fieldbus
Error Cause
Instrument does Profibus DP cable
not appear during pole-reversed
connection setup
Incorrect termi-
nation
Instrument not
connected to the
segment
In Ex applications, the regulations for the wiring of intrinsically safe
circuits must be observed.
Error code Cause
E013 no measured value
available
E017 Adjustment span too
small
E036 no operable sensor
software
E041 Hardware error, elec-
tronics defective
E113 Communication con-
flict
8.3 Calculation of total deviation (according to
DIN 16086)
The total deviation F
total
accuracy F and longterm stability F
perf
practical deviation or utility error.
F = F + F
total perf stab
F = √((F ) + (F ) )
2 2
perf T Kl
With the analogue signal output there is also the error of the current
output F .
a
F = √((F ) + (F )
2 2
perf T Kl
With:
•
F : Total deviation
• total
F : Basic accuracy
• perf
F : Long-term drift
• stab
F : Temperature coefficient (influence of medium or ambient
T
temperature)
•
F : Deviation
Kl
•
F : Error current output
a
Level measurement 1500 mmWs
Fault message can also appear if the pressure is higher than the nominal
9)
range.
8 Maintenance and fault rectification
Rectification
Check cable and correct, if necessary
Check termination at the beginning
and end points of the bus and termi-
nate, if necessary, according to the
specification
Check and correct, if necessary
Rectification
– Exchange the instrument or send it
in for repair
9)
– repeat with modified values
– Carry out a software update or send
instrument for repair
– Exchange the instrument or send it
in for repair
– Exchange the instrument or send it
in for repair
according to DIN 16086 is the sum of basic
. F
stab
(+ F ) )
2
a
is also called maximum
total
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