Vega EL 11 User manual

Level and Pressure
Operating Instruction
Capacitive electrodes EL
4 … 20 mA - compact

2 Capacitive electrodes EL 4 … 20 mA - compact
Safety information
Safety information
The described module must only be installed and
operated as described in this operating
instruction. Please note that other action can
cause damage for which VEGA does not take
responsibility.

Capacitive electrodes EL 4 … 20 mA - compact 3
Contents
Safety information ......................................................................... 2
1 Product description
1.1 Function and configuration ................................................... 4
1.2 Types and versions ............................................................... 5
1.3 Technical data ....................................................................... 7
1.4 Approvals ............................................................................ 13
1.5 Dimensions ......................................................................... 14
1.6 Type plate ........................................................................... 16
2 Mounting
2.1 Mounting instructions .......................................................... 17
3 Electrical connection
3.1 Connection instructions ...................................................... 22
3.2 Wiring plan .......................................................................... 22
4 Set-up
4.1 General adjustment ............................................................ 26
4.2 Adjustment - Oscillators
CAP E32 Ex and CAP E32 H Ex ......................................... 27
4.3 Adjustment with VVO ............................................................ 30
4.4 Adjustment with HART®-handheld ..................................... 36
5 Diagnosis
5.1 Simulation ........................................................................... 44
5.2 Maintenance ....................................................................... 44
5.3 Repair ................................................................................. 44
5.4 Failure removal .................................................................... 45
Contents

4 Capacitive electrodes EL 4 … 20 mA - compact
Product description
1 Product description
1.1 Function and configuration
Capacitive electrodes series EL detect levels of
virtually any medium unaffected whether
liquids, powders or pastes. This is also valid for
adhesive products.
The electrode measures also the level
capacitance and the ohmic resistance
(admittance processing). Hence also
problematic medium and solids with fluctuating
humidity contents can be detected.
By the use of screening tubes and screen
segments, inactive areas can be provided on
the probe where pollution, condensation or
permanent build-up do not influence the
measuring result.
Measuring principle
Electrode, medium and vessel wall form an
electrical capacitor.
The capacitance of the capacitor is mainly
influenced by three factors:
- distance of the electrode plates (a)
- size of the electrode plates (b)
- kind of dielectricum between the electrodes
(c)
Fig. 1.1 Plate capacitor (schematic
demonstration)
Electrode and vessel wall are the capacitor
plates. The medium is the dielectricum. Due to
the higher dielectric constant figure (DK-value)
of the medium against air, the capacitance of
the capacitor increases with raising covering of
the electrode.
Fig. 1.2 Capacitance change with covered
electrode
a
b
c
The capacitance change is processed by the
oscillator and converted into a level proportio-
nal measured value. The measured value is
provided analogue as standardized, floating
4 … 20 mA-current signal, optionally also
digitally with the HART®-communication
protocol.
The sensor can be adjusted via the integral
oscillator. Optionally the adjustment with
HART®-handheld or PC with VVO-adjustment
software is also possible.
With the continuous level measurement the
appropriate level is continuously detected and
converted into a level proportional signal which
is either directly displayed or further processed.
You require a capacitive electrode series EL
with oscillator CAP E32 Ex or CAP E32 H Ex.
The continuous measurement assumes a
constant dielectric constant figure εr, i.e. the
medium should have steady features.

Capacitive electrodes EL 4 … 20 mA - compact 5
Product description
*) also Ex 0
1) applied
2) 1.4435
3) 1.4571
4) 1.4401
5) For electrodes certified for Ex-Zone 0,only PTFE and FEP are approved as isolating material
1.2 Types and versions
Type EL EL EL EL EL EL EL EL EL
Version 11*)21*)24*)29 31*)33 42*)52 53
Continuous •••••••••
Partly-insulated • • •
Fully-insulated • • • • • •
Oscillators
CAP E32 EX •••••••••
CAP E32 H EX •••••••••
Approvals
PTB 98 ATEX 2086 • • • • •
PTB-no. Ex-98.E.2085 • • • • •
Overfill protection
acc. to WHG1) ••••• •
German Lloyd1) •••••••••
Lloyds Register of Ship1) •••••••••
American Bureau of Ship1) •••••••••
Bureau Veritas1) •••••••••
RINA1) •••••••••
Mechanical connection
G 1 A • • • • • •
NPT 11/2" •• ••••••
G 11/2A ••• •••••
Tri-Clamp 11/2“••
Tri-Clamp 2“ • • • • •
Bolting
DN 50 • • •
Flange • • • • ••••
Flange plated •
Screw adapter
PP ••• ••
PTFE • • • •
Electrode material
Steel • • • ••••
StSt •2) •2) •2) •3) •3) •4) •2) •2)

6 Capacitive electrodes EL 4 … 20 mA - compact
Type EL EL EL EL EL EL EL EL EL
Version 11*)21*)24*)29 31*)33 42*)52 53
Isolation material5)
PTFE • • • • • •
PP • •
PE/PA 12 •
PFA •
FEP • •
PE •
Concentric tube
Steel • • •
StSt (1.4435) • • •
Screening tube (option)
Steel • • • • • • • •
StSt • • • • • • • •
Temperature
adapter (option)
Steel • • • • •
StSt (1.4435) • • • • •
PA • • • • • • •
Housing material
Plastic • • • • • • • • •
Aluminium • • • • • • • • •
Others
Adapter 6) •• • •
Overvoltage protect.-option
CB-2-36 (integrated) • • • • • • • • •
Overvoltage arrester 7) •• ••
Bending of
electrode 8) ••
9)
*) also Ex 0
1) applied
2) 1.4435
3) 1.4571
4) 1.4401
5) For electrodes certified for Ex-Zone 0, PTFE and FEP are only approved as isolation material
6) For combustible liquids in pressurized vessels, e.g. liquid gas, ammonia
7) For high electrostatic discharges, e.g. plastic granules
8) Bending max. 90°
9) EL 21 only with PTFE at 3,2 mm isolation thickness
Product description

Capacitive electrodes EL 4 … 20 mA - compact 7
Product description
1.3 Technical data
Housing
Housing material plastic PBT (Polyester) or Aluminium
plastic coated
Protection
- plastic housing IP 66
- Aluminium housing IP 66/67 (meets both protections)
Cable entry 1 piece M20 x 1,5
Terminals for max. 1,5 mm2cross-section area of conductor
Mechanical connection
Material galvanized steel (St 37), 1.4571 (StSt), Aluminium
Thread G 11/2A or 11/2" NPT
Flange flange versions
Electrode
Material EL 11 1.4435 (316 L)
EL 21 steel (St 37)
EL 31 1.4401 (316 L)
EL 24, 42 1.4571 (316 L)
Length
- rod max. 3 m
- cable max. 20 m
Isolation see "Isolation materials"
Max. tensile load (cable)
- EL 31 3 KN
- EL 33, 34, 42, 52, 53 3 KN
Ambient conditions
Ambient temperature on the housing -40°C … +80°C
Medium temperature see "Medium temperature and operating pressure"
Storage and transport temperature -40°C … +80°C
Operating pressure see "Medium temperature and operating pressure"
Oscillator CAP E32 Ex, CAP E32 H Ex
Protection class II
Overvoltage category III
Meas. frequency 300 KHz
Capacitance ranges 0 … 3000 pF

8 Capacitive electrodes EL 4 … 20 mA - compact
Oscillators in two-wire technology for capacitive electrodes EL
Type Application Meas. range Freguency Signal cond.instr.
CAP E32 Compact electronics 4 … 20 mA for 0 - 3000 pF 300 KHz not required
Ex continuous level measurement,
according to the principle of
phase selective admittance processing
Parameter adjustment via
keys on the oscillator
CAP E32 H Compact electronics 4 … 20 mA for 0 - 3000 pF 300 KHz not required
Ex continuous level measurement,
according to the principle of
phase selective admittance processing
Parameter adjustment via
keys on the oscillator,
VVO from V. 2.30 or
HART®-handheld
Accessory
Straining spring of 1.4571
- length approx. 185 mm (stressed)
- tensile load approx. 200 N
Weight
Basic weight (e.g. EL 24) approx. 0,8 kg
Rod weight ø 6 mm - 0,23 kg/m
ø 10 mm - 0,62 kg/m
Product description
12
200
600
800
18 24 30 36
1000
Load in Ω
Supply
voltage in V
Supply voltage 12 … 36 V DC
for Ex-applications note the stated permissible
electrical connection values in the certificate.
Potential separation min. 500 V AC

Capacitive electrodes EL 4 … 20 mA - compact 9
Product description
+
–0 % 5 % 10 %
15 % vol.
fully insulated
electrode
partly
insulated
electrode
Solid
humidity (%)
Level
measured
value
Fig. 1.3 Humidity change
Oscillator
The oscillator CAP E32 (H) Ex with the patented
processing (phase selective admittance
processing) extends the application range of
capacitive level measurement technology. This
function can be switched on, see 4 Set-up.
In conjunction with a fully insulated rod
electrode, the oscillator compensates even
strong conductive build-up.
Mounted in an individual rod or cable electrode
type EL, this oscillator ensures also the exact
measurement in solids with varying humidity
contents.
The oscillator processes the measuring
currents according to the phase position.
Measuring currents with a defined phase
shifting as they occur with build-up or humidity
changes are filtered out.
Humidity change
A humidty change in solids causes a change of
the dielectric constant figure (εr). In parallel the
ohmic value of the medium changes. Due to the
change also a phase shifting of the measuring
currents is caused.
With a capacitive measurement already lowest
humidity changes cause measuring errors.
Typical products are, e.g. sand, aggregate in
the cement industry, hop or plastic granules
(after drying).
When using the oscillator CAP E32 (H) Ex
humidity changes of 15␣ % vol. do not influence
the accuracy of the measurement. Even
layering of product with different humidity do
not play a role for the measuring accuracy.
When the humidity contents exceeds 15␣ % vol.
1) Actual value level
1)
fully and partly insulated electrodes react
differently (see also “Fig. 1.3 Humidity
change“). Whereby the measured value on fully
insulated electrodes raises with steady level,
the measured value on partly insulated
electrodes drops.

10 Capacitive electrodes EL 4 … 20 mA - compact
Product description
0
–10 60 80
40
°C
bar
16
0
–10 100
63
°C
bar
6
5
4
0
–10 100
63
200 °C
bar
25
EL 21, 53:
PE and PE / PA 12
up to 16 bar
Temperature
adapter 2)
EL 42:
up to 16 bar
EL 24:
up to 40 bar
from 100°C
unpressurized
max. 150°C for
30␣ min.
0
–50 100
63
200 °C
bar
25
0
–50 100
63
°C
bar
0
–30 60 80
40
bar
°C
16
3
2
1
EL 21, 53:
PE and PE / PA 12
up to 16 bar
Temperature
adapter 1)
EL 42:
up to 16 bar
EL 24:
up to 40 bar
from 100°C
unpressurized,
max. 150°C for
30␣ min.
1) Temperature adapter of PA up to 150°C, from 100°C
unpressurized
Medium temperature1) and operating
pressure1)
The figures in the tables relate to the figures on
this page. The statements on pressure are valid
for screw conenctions G 11/2A, NPT 11/2“ and R
11/2.
Boltings DN 50 acc. to DIN 11␣ 851 only up to
max. 25 bar. With flange versions you have to
note their nominal pressure.
All electrodes are also suitable for vacuum
(-1␣ bar).
For electrodes certified for Ex-Zone 0, only
PTFE and FEP are approved as isolating
material.
Mechanical connection, 1.4571
Isolation
Electrode type
EL 11 - 1 3 - - -
EL21 1-3-3-
EL 21 (flange) - - 2 - - -
EL24 -----2
EL 29 - - 2 - - -
EL 31 - 1 3 - - -
EL 33 - - 3 - - -
EL 42 - - 2 - - -
EL 52 - - 3 - - -
EL 53 - - - 1 - -
Mechanical connection, steel (St 37)
Isolation
Electrode type
EL 11 - 4 6 - - -
EL21 4-6-6-
EL 21 (flange) - - 5 - - -
EL24 -----5
EL 31 - 4 6 - - -
EL 33 - - 6 - - -
EL 42 - - 5 - - -
EL 52 - - 6 - - -
EL 53 - - - 4 - -
PE PP PTFE PE/PA 12 PFA FEP
PE PP PTFE PE/PA 12 PFA FEP

Capacitive electrodes EL 4 … 20 mA - compact 11
8
7
0
–30 100
16
°C
bar
0
–30 60 80
16
°C
bar
Mechanical connection, Aluminium
Isolation
Electrode type
EL 11 - 7 8 - -
EL 21 7 - 8 - 8
EL 31 - 7 8 - -
EL 33 - - 8 - -
EL 42 - - 8 - -
EL 52 - - 8 - -
EL 53 - - - 7 -
Mechanical connection, PP, PVC, PTFE,
screwed adapter
Isolation
Electrode type
EL 29 10 10 10
PE PP PTFE PE/PA 12 PFA
1) For Ex-applications the permissible temperatures and pressures stated in the certificate must be noted.
Additionally note the table on the following page.
2) Temperature adapter of PA up to 150°C, from 100°C unpressurized
FEP
9
0
–20 60 °C
bar
2
45
1
PP PTFE
PP: unpressurized up
to 80°C
PTFE: 3 bar,
-20␣ …␣ 100°C
Product description

12 Capacitive electrodes EL 4 … 20 mA - compact
Product description
Electronics temperature
The following medium and ambient
temperatures must be kept, so that the limit
temperature on the electronics is not exceeded.
Temperature class T4 (or no Ex)
Without temperature adapter
- medium temperature -40°C … +135°C
- ambient temperature1) -40°C … +90°C
Temperature class T3
With temperature adapter
1) Ambient temperature on oscillator
Plastic housing Metal housing
Medium temperature -40°C … 180°C 200°C 150°C 175°C 200°C
Ambient temperature1) -40°C … 80°C75°C80°C69°C58°C
Product description

Capacitive electrodes EL 4 … 20 mA - compact 13
Product description
1.4 Approvals
Explosion protection
Only certified capacitive electrodes EL** Ex 0
must be used in hazardous areas with
combustible gases, vapours or fog.
Capacitive electrodes EL** Ex 0 are suitable for
the use in hazardous areas of zone 1 and zone
0.
Proof for the explosion protection of these
instruments is the EC-type approval and the
conformity certificate possibly with national
zone 0 - annex issued by the approval
authority. These documents are generally
attached to the instruments.
When the capacitive electrodes are mounted
and operated in hazardous areas, the Ex-
installation regulations must be noted.
The information and regulations of the supplied
certificates (EC-type approval, conformity
certificate) of the capacitive electrodes as well
as of the appropriate instrument (signal
conditioning instrument, separator, safety
barrier) must be noted.
• The mounting of Ex-systems must be
generally carried out by skilled staff.
• The capacitive electrodes must be powered
from an intrinsically safe circuit; the
permissible electrical values are stated in the
appropriate certificate.
• Capacitive electrodes with electrostatically
chargeable plastic parts are provided with a
warning label informing about measures
which must be taken to avoid dangers
caused by electrostatic discharges. Note the
contents of the warning label.
• The explosion protection of the instrument
used is only ensured when the limit
temperatures stated in the certificate are not
exceeded.
• In case of danger due to oscillation or
vibration, the appropriate parts of the
capacitive electrodes must be protected.
• After shortening of the electrode cable it
must be noted that the weight is sufficiently
secured by means of pins.
Overfill protection acc. to WHG
The information and regulations of the supplied
type approvals must be noted when a
capacitive electrode is used as overfill
protection for vessels storing water
endangering liquids. The general type approval
must be available on site.
Electrodes must be only used in such liquids
against which the materials of the wetted parts
of the capacitive electrodes are sufficiently
chemically resistant.
Ship approvals
For the use on ships, type approval certificates
are available of several ship classification
authorities (GL, LRS, ABS, BV, RINA).
CE-approval
The capacitive electrodes type EL meet the
protective regulations of EMVG (89/336/EWG)
and NSR (72/23/EWG). The conformity has
been judged acc. to the following standards:
EMVG Emission EN 50 081 - 1
Susceptibility EN 50 082 - 2
NSR EN 61 010 - 1
Zone 2
According to DIN VDE 0165, instruments can
be used in hazardous areas of zone 2 without
approval; they must meet the requirements in
section 6.3 of this VDE. The compliance of the
instruments with these requirements is
confirmed by Messrs. VEGA in a manufacturer
declaration.

14 Capacitive electrodes EL 4 … 20 mA - compact
Product description
1.5 Dimensions
Dimensions of the capacitive electrodes type EL … Ex 0
Type EL 11
(partly insulated)
(Ex 0)
SW 60
M20x1,5
90
85 32,5
ø20
L1
ø15
35
L
20
G 11/2A
L (min. 100 mm, max. 4000 mm)
Type EL 21 (fully insulated)
(Ex 0)
SW 60
35
A
L
20
M20x1,5
90
85 32,5
G 11/2A
L (min. 100 mm, max. 4000 mm)
Isolation length L1:
PP: 100 mm
PTFE: 50 mm
StEx: max. 100 mm
Type EL 24 (fully insulated,
for adhesive products)
(Ex 0)
20
35
ø12
ø14
L
M20x1,5
90
85 32,5
SW 60
G 11/2A
L (min. 120 mm, max. 4000 mm)
Type EL 29
(fully insulated)
25
ø14
48
L
M20x1,5
90
85 32,5
L (min. 120, max. 3000 mm)
Type EL 31 (partly insulated)
(Ex 0)
L (min. 400 mm, max. 25000 mm)
Isolation length L1:
PP: 100 mm
PTFE: 50 mm
StEx: max. 100 mm
,
,
,
109
200 35
L1
L
ø40 71 16
ø8
ø20
20
M20x1,5
90
85 32,5
Isolation A
outer-ø
PE 2,0 mm 20 mm
PTFE 2,0 mm 20 mm
PTFE 3,2 mm 16 mm
PFA 2,0 mm 20 mm
,,
,,
,,
,,
ø3
,,
,,
,,
,,
,,
,,
,,
,,
,,
ø5
35
ø3
ø40
200
L
120
ø20
36
ø40
20
M20x1,5
90
85 32,5
Type EL 42 (fully insulated)
(Ex 0)
L (min. 400 mm, max. 25000 mm)
SW 60
SW 60

Capacitive electrodes EL 4 … 20 mA - compact 15
Product description
Housing
Housing of plastic / Aluminium
M20x1,5
90
32,5
85
Temperature adapter
Adapter
for combustible liquids in pressurized
vessels, e.g. liquid gas, ammonia
Concentric tube
Screening tube
ø38
L
SW 60
of galvanized steel
or 1.4571
SW 60
ø45
54
ø60
ø60
70
Temperature adapter
,,
,,
,,
,,
,,
,,
10
ø38
L
of St or 1.4571 with
closing cone of PP or
PTFE
of St or 1.4571
of PA, for
temperatures up
to 150°C, from
100°C only
unpressurized
200
90
ø66
ø66
G 11/2A
,,,,,,,
,,,,,,,
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,,,,,,,
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,,,,,,,
,,,,,,,
,,,,,,,
,,,,,,,
,,,,,,,
,,,,,,,
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,,,,,,,
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20 44
Screwed adapter of
PP or PTFE
Closing cone
Type EL 52 (fully insulated)
M20x1,5
90
85 32,5
125
35
L
ø40
ø40
ø20
36
ø15,5
ø8
200
20
M20x1,5
90
85 32,5
120
L
ø40
ø40
ø20
36
ø11
ø6
200 35
20
Type EL 53 (fully insulated)
L (min. 400 mm, max. 25000 mm)L (min. 400 mm, max. 25000 mm)

16 Capacitive electrodes EL 4 … 20 mA - compact
ser. no. 10612892
Product description
1.6 Type plate
Before mounting and electrical connection
please check if you use the suitable instrument.
Therefore note the type plate which is located
as follows:
1 Master data of the order no.
2 Ex-certification number
Explosion protection version - note the
information and regulations of the certificate
3 Data of the electronics / Approvals
4 No. of the order confirmation /Pos.-no.
5 Number of the electrode type
6 Serial number
7 Test mark when used as part of an overfill
protection for vessels storing water
endangering liquids - note the information
and regulations in the general type approval
8 Manufacturing year
9 Number of the test authority
Type plate
The type plate contains important data required
for mounting and connection. The configuration
and components of the type plate are hence
explained in the following example.
Configuration of the type plate (example)
Order code
Detailled information on the order you will find
in the “Product Information Capacitive“ or in the
“VEGA-Pricelist“.
6
VEGA®EL 11
type EL11EXO.XGBVSTXXVKXX
see PTB Nr. EX-98.E.2085 EEx ia IIC T6 0032
PTB 98 ATEX 2086 II 1/2G EEx ia IIC T6
techn. data see document. / certificates 1998
protection: IP 66/67 Insp.
length: 400mm VVO: 02
Ord. no. 123456/000
3
1
4
2
®D-77757 Schiltach
5
Z-65.13.XXX
7
9
8

Capacitive electrodes EL 4 … 20 mA - compact 17
Mounting
Fig. 2.1 Lateral load
2 Mounting
2.1 Mounting instructions
General
Different mediums and requirements to the
measurement require various installations.
Hence the following instructions should be
noted.
Lateral load
Note that the electrode is not subjected to
strong lateral forces. Mount the electrode in a
position in the vessel where no interfering
influences such as e.g. stirrers, filling opening
etc. occur. This is mainly valid for very long rod
and cable electrodes.
Extraction forces
In case of strong extraction forces e.g. during
filling or settling of solids, high tensile loads can
be caused.
In these cases use for short measuring
distances a rod electrode, as a rod is generally
more stable. If due to the length or the
mounting position a cable electrode should be
necessary, the electrode should not be
strained, but only equipped with a gravity
weight as then the cable can more easily follow
the product movements. Note that the electrode
cable does not touch the vessel wall.
Pressure
In case of gauge or low pressure in the vessel,
the mounting boss must be sealed on the
thread. Use the attached seal ring. Check if the
seal ring is resistant against the medium.
Isolating measures such as e.g. the covering of
the thread with Teflon tape can interrupt the
electrical connection in case of metal vessels.
Hence earth the electrode on the vessel.

18 Capacitive electrodes EL 4 … 20 mA - compact
Fig. 2.3 Humidity
Mounting
Fig. 2.2 Shortening of the electrode
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Shortening of the electrode
The dimensions of fully insulated electrodes are
fixed and must hence not be modified. Each
modification will destroy the instrument.
Partly insulated cable or rod electrodes can be
shortened afterwards.
The electrode basic capacitance is automa-
tically compensated during adjustment. It is
hence possible to shorten the electrodes
individually.
Cable electrode EL␣ 31 can also be shortened
afterwards (see fig. 2.2). Loosen the two pins
on the gravity weight (hexagon) and remove the
two pins. Pull the cable out of the gravity
weight.
To avoid splicing of the steel cable (EL␣ 31)
during cutting, you have to tin the cable around
the cutting position with a copper bit or strongly
tighten the cable with a wire. Shorten the
electrode cable with a metal cutting saw or a
cutting-off wheel by the the requested length.
Carry out the adjustment. The instruction is
under “4.1 Adjustment“.
Filling opening
Install the electrode such that it does not
protrude directly into a strong filling stream.
Should such an installation place be necessary,
mount a suitable sheet above or in front of the
electrode e.g. L␣ 80␣ x␣ 8 DIN 1028, etc.
Humidity from outside
To avoid humidity ingress, loop the connection
line to the electrode housing on vertically
installed electrodes directly behind the cable
entry to the bottom so that rain and
condensation water can drain off.
This is mainly valid for mounting outside, in
areas where humidity must be expected (e.g.
by cleaning processes) or on cooled or heated
vessels (see fig. 2.3).
Cable entries
When mounting outside, on cooled vessels or in
humid areas where cleaning is made e.g. with
steam or high pressure, the seal of the cable
entry is very important.
Use cable with a round cross-section area of
conductor and tighten the cable entry. The
cable entry is suitable for cable diameters of
5␣ mm to 9␣ mm.
Metal vessels

Capacitive electrodes EL 4 … 20 mA - compact 19
Mounting
Note that the mechanical connection of the
electrode is electrically conductive connected
with the vessel to ensure sufficient earth.
Use conductive seals such as e.g. copper, lead
etc. Isolating measures such as covering the
thread with Teflon tape can interrupt the
necessary electrical connection. In this case
use the earth terminal on the housing to
connect the electrode to the vessel wall.
Non-conductive vessels
In non-conductive vessels, e.g. plastic tanks,
the second pole of the capacitor must be
provided separately, e.g. by a concentric tube
or the use of a double rod electrode.
When using a standard electrode, a suitable
earth plate is necessary. Hence provide a
possibly large earth plate, e.g. wire braiding
laminated into the vessel wall or metal foil which
is glued to the vessel. Connect the earth plate
with the earth terminal on the housing.
Rod electrode
Mount the rod electrode such that the electrode
protrudes into the vessel. When mounting in a
tube or a socket, build-up can be caused which
can influence the measurement. This is par-
ticularly the case with viscous or adhesive
products.
Cable electrodes in solids
Dependent on the kind of solid and position or
kind of filling, the cable electrode can “float“
despite of the gravity weight. The electrode
(cable) is pushed by the solid to the vessel wall
or to the top and wrong measured values are
caused. This should be avoided with
continuous level measurement.
In this case use a fixing weight or a fixing
insulator to fasten the electrode (fig. 2.4).
When fastening the cable electrode avoid high
tensile strenghts. An appropriate fixing spring
avoiding overloading of the cable is listed in our
pricelist as accessory.
Lateral installation
Fig. 2.4 Cable electrode in solids

20 Capacitive electrodes EL 4 … 20 mA - compact
L
Fixing weight
Mounting
With electrodes, delivering continuous
measured values, the electrode must only be
installed vertically. Should the installation from
top not be possible, the electrodes can also be
mounted laterally (fig. 2.5)
Under the accessory in our pricelist you find a
screening tube and a closing cone or a bent
rod electrode by which the electrode can be
also mounted laterally. Choose the length (L) of
the screening tube such that no product
bridges can be caused between cable and
vessel wall and that the electrode cable cannot
touch the vessel wall due to product
movements. Use a fixing weight or a fixing
insulator.
Material cone
Fig. 2.5 Continuous electrodes