18
WIKA Operating instructions - Submersible pressure transmitter model LH-20
Configuration
2
1
Abb. 9: Configuration of the gauge probe model LH-20
1 Transmitter
2 Suspension cable
Type label
The type label contains the most important data
for identification and use of the instrument:
1
2
3
5
6
4
7
8
9
10
11
12
Abb. 10: Type plate of model LH-20 (example for versi-
on 4 … 20 mA/HART)
1 Instrument
2 Measuring range
3 Operating voltage
4 Article number
5 Serial number
6 Product number
7 Wire assignment suspension cable, temperature
8 Protection rating
9 Signal output
10 Deviation
11 Wire assignment suspension cable, level
12 Reminder to observe the instrument documentati-
on
2.2 Principle of operation
Application area
Model LH-20 is suitable for continuous level
measurement of liquids. Typical applications are
measurements in water/waste water facilities,
deep wells and in the shipbuilding industry.
Functional principle
The actual sensor element is a measuring cell
with rugged ceramic diaphragm. The hydrostatic
pressure causes a capacitance change in the
measuring cell via the ceramic diaphragm. This
change is converted into an appropriate output
signal.
Voltage supply
4 … 20 mA two-wire electronics for voltage
supply and measured value transmission on the
same cable.
The data for power supply are specified in chap
-
ter "
Technical data
".
2.3 Operation
The instrument can be adjusted with the fol-
lowing adjustment media:
•
With the external display and adjustment
instruments DIH50, DIH52 and DIH62
•
an adjustment software according to FDT/
DTM standard, e.g. PACTware and PC
•
With a HART handheld
The type of adjustment and the adjustment
options depend on the selected adjustment
component. The entered parameters are
generally saved in the respective sensor, when
adjusting with PACTware™ and PC optionally
also in the PC.
2.4 Accessories and replace-
ment parts
Interface adapter
The optionally available HART modem with
RS232, USB or Bluetooth interface enables the
connection of communication-capable instru-
ments to the respective interface of a PC. An
adjustment software like PACTware with COMM
DTM HART and Device DTM Generic HART is
necessary for parameter adjustment of these
instruments.
The adjustment software PACTware and the
required DTMs is available free-of-charge under
External display and adjustment units
DIH50, DIH52 and DIH62
The adjustment units DIH50, DIH52 and DIH62
are suitable for measured value indication and
adjustment of sensors with HART protocol. The
respective adjustment unit is looped into the
