Siemens Sitrans LR250 Operating Instructions Manual page 10

Short
Long Form
form
DCS Distributed Control System
dK dielectric constant
EDD Electronic Device Description
I Input current
i
I Output current
o
IS Intrinsically Safe
L Internal inductance
i
mH milliHenry
μF microFarad
μs microsecond
Process Automation
PA
(PROFIBUS)
PED Pressure Equipment Directive
pF pico Farads
ppm parts per million
PV Primary Value
PVDF Polyvinylidene fluoride
SELV Safety extra low voltage
SV Secondary Value
TB Transducer Block
TVT Time Varying Threshold
U Input voltage
i
U Output voltage
o
a)
The output from the Level Transducer Block can be called the Primary Value (or
Secondary Value). When it becomes the input to the AIFB, it is called the
Process Variable.
Page 4 SITRANS LR250 (PROFIBUS PA) – OPERATING INSTRUCTIONS
Description
control room apparatus
safety approval
10
10
10
safety approval
10
a)
measured value
a)
equivalent value
sensitivity threshold
-3
-6
-6
-12
Units
(cont' d )
mA
mA
mH
Henry
Farad
Second
Farad
V
V
7ML19985JF04