NIVELCO NIVOROTA EL 7 Series User manual

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1. INTRODUCTION
The new NIVOROTA E-700/800 rotary paddle level switches of the well-known NIVELCO design can be
used for detecting the level of lumpy materials, powders, and granules. Mounted onto tanks, silos, and
hoppers, they monitor and control the level, filling, and emptying of stored materials such as stones, fly ash,
sand, coal, feed, beet slices, etc.
A low-power electric motor drives the paddle, which rotates freely in the absence of the material. Its rotation
in the EK/H is mono-directional; in the EL/M, it is bidirectional. When the medium reaches the paddle, the
output contact switches from NC state to NO state, and the motor is turned off. When the material level
drops, the paddle runs free again, the motor is reactivated, and the switch returns to its original state (NC).
In the case of low-level detection, the material usually covers the blade, with the output contact staying in NO
state, and the motor stopped. When the material drops to a level where the paddle can rotate freely again,
the motor restarts and the control switch returns to the NC position.
The process connection can be threaded (1" or 1½" BSPT) or a mounting plate. It is recommended to use
adapters for threaded connection points other than the standard version. The mounting plate can be attached
to the unit with a threaded process connection. Mounting nuts are available for mounting onto a bracket,
depending on the size of the process connection. A suitable paddle must be chosen for every particular
medium density. The single-blade paddle is recommended for higher density materials and granular solids,
while the 3-blade paddle is recommended for lower density materials, powders, and solids. The 1-blade or
2-blade paddle can also be used with a suitable threaded connection, while the 3-blade paddles can only be
installed using a mounting plate.
If the standard version's insertion length is not enough, there are rod or cable extension types available,
depending on the application. For light materials with moderate stress, the solution is to use Ø10 pipe
extension. The device's shaft must be protected against being hit by falling stones or other coarse materials
by using a flexible coupling. If the insertion length is customized for any technical reason, the rod-extended
design with an adjusting unit is recommended. This can be ordered separately. In the case of a cable
version, if the desired length falls between two available sizes, the desired length can be achieved by cutting
the cable to the appropriate size. The counterweight stretches the cable to avoid the paddle climbing up onto
the medium surface. If additional stiffening of the cable probe is required, a rigid pipe can be ordered as an
accessory. Caution! If the pipe is cut to size, at least 30 mm (1.2 inches) must be left free between its top end
and the cable rope assembly connector.
If the medium temperature exceeds 120 °C (248 °F), a high-temperature version must be used, equipped
with a heat sink, raised from the process connection, and only available with aluminum housing. Dust-Ex
versions are available for use in hazardous environments.
2. TECHNICAL DATA
2.1 GENERAL DATA
Version Standard High-temperature
EM/ EH– 7
EL/ EK– 7 EL/ EK– 8
Insertion length (L) Standard: 200 mm (7.85 inches) – Rod extension: 0.4 – 3 m (1.3 – 10 ft)
Cable extension: 1 m – 3 m (3.3 – 10 ft)
Number and material of
the blades 1.4571 (316Ti) / 1, 2, 3; as per order code
Rotation speed ~1 rpm (@50 Hz)
Material of wetted parts 1.4571 (316Ti) Stainless Steel, Material of the seal: NBR
1.4571 (316Ti) Stainless
Steel, Material of the seal:
FPM
Medium density
(guideline value) min. 0.1 kg/dm3
Medium temperature
-20 °C …+120 °C
(-4 °F …+248 °F)
-20 °C …+80 °C
(-4 °F …+176 °F)
-20 °C …+200 °C
(-4 °F …+392 °F)
Ex variant: see Special data for Ex certified models
Ambient temperature -30 °C … +60 °C (-22 °F … +140 °F)
Relative humidity max. 90%
Process pressure max. 3 bar (0.3 MPa, 43.5 psig)
Output SPDT 250 VAC, 6A, AC1
Paddle-rotation /
shutdown indication Two-toned (green/red) LED
Power supply Nominal value: 230 VAC (50/60 Hz) +10% -15%, 120 VAC (50/60 Hz) +10% -15%
24 VAC (50/60 Hz) +10 % -15%, 24 VDC (18–28 VDC)*
Process connection 1" BSPT; 1½" BSPT; mounting plate
(BSPT thread can also be screwed into BSP or NPT thread)
Power consumption max. 4 VA (4 W)
Electrical connection
2x M20x1.5 plastic cable glands, for 6 – 12 mm (0.25 – 0.5 inches) cable + Two internally
threaded ½" NPT connection for protective pipes 2x terminal blocks for 0.5 – 1.5 mm2
(AWG20 – AWG15) wire cross section
Electrical protection Class I
Ingress protection IP67
Housing material Powder-coated aluminum Plastic (PBT) Powder-coated aluminum
Weight Standard: 1.6 kg (3.52 lb), Rod-extended: 1.6 kg (3.52 lb) + extension 1.6 kg/m (1 lb/ft),
Cable-extended: 2.6 kg (5.73 lb) + extension 1.4 kg/m (0.94 lb/ft), counterweight: 1 kg (2.2 lb)
2.2 EX SPECIAL DATA FOR EX CERTIFIED MODELS
Electrical
connection
2x M20x1.5 metal cable glands, cable outer
diameter: 8 – 13 mm (0.31 – 0.51 inches)
Ex marking II 1/2 D Ex tb IIIC IP67
TEMPERATURE DATA FOR EX VERSIONS
Type Standard type High-temperature type
Temperature class
Max. surface temp
Medium temperature
Ambient temperature
Waiting time for opening
the cover
Max. surface temp
Medium temperature
Ambient temperature
Waiting time for opening
the cover
T85°C 85 °C
60 °C
30 min 85 °C
60 °C
30 min
T100°C 100 °C 20 min 100 °C 20 min
T135°C 120 °C 50 °C 5 min 120 °C 5 min
T200°C - 200 °C 0 min
2.3 ACCESSORIES
User’s manual
Warranty Card
EU Declaration of Conformity
1-, 2- or 3-blade paddle (as per order
code), 2 pcs. split pin
* Types EK/EH--4M,-8M use 24 VDC (-15%...+10%)
The connection between the device housing and the process connection is rigid, it cannot be turned or twisted

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2.4 ORDER CODE
E – – (1)
Version Code Probe version / Paddle /
Process connection Code Housing Code Code Insertion length Code Power supply / Certificate Code
Standard K
Standard / Single-blade
paddle / 1" BSPT A
A
luminium 7 0 0 m 0 m 0 230 VAC 1
High-temperature H Plastic (2) (3) 8
1 1 m 0.1 m 1 120 VAC 2
Standard bidirectional
version L Standard / Single-blade paddle / 1½" BSPT H 2 2 m 0.2 m 2 24 VAC 3
33 m 0.3 m 3 24 VDC 4
High-temperature
bidirectional version M Standard / 3- blade paddle / 1½ " BSPT F 0.4 m 4 230 VAC/Ex tb IIIC (ATEX) 5
0.5 m 5 120 VAC/Ex tb IIIC (ATEX) 6
With rod extension / Single-
blade paddle / 1½" BSPT R 0.6 m 6 24 VAC/Ex tb IIIC (ATEX) 7
With cable extension / Single-
blade paddle / 1½" BSPT K 0.7 m 7 24 VDC/Ex tb IIIC (ATEX) 8
0.8 m 8
With cable extension /
3-blade paddle / 1½" BSPT L 0.9 m 9
(1) The order codes of Ex versions end in ’Ex’ (2) No Ex version available (3) No high-temperature variant available
Accessories
Paddles Mounting plate Accessories
Type / material Code Type / material Code Type / material Code
Single-blade curved, 168 mm / 1.4571 EAL-701-1 1" female nut / 1.4571 EAM-701-0 Weight / 1.4571 EAW-701-0
Single-blade curved, 120 mm / 1.4571 EAL-702-1 1½" female nut / 1.4571 EAM-702-0 Flexible Coupling / Stainless steel EAS-701-0
2-blade flexible, 172 mm / 1.4571 EAL-703-1 Sliding sleeve for rod extended version
/ 1.4571 EAM-703-0 Rigid pipe for cable extended version (0,1 – 3,0 m) EAK-7-1 (2)
2-blade flexible, 120 mm / 1.4571 EAL-704-1
Single-blade straight, 170 mm / 1.4571 EAL-705-1 Mounting plate, 1" hole / 1.4571 EAM-704-0 Pipe extension Ø10x1 (0,1
–
0,5 m) EAR-70-1 (2)
Single-blade straight, 70 mm / 1.4571 EAL-706-1 Mounting plate, 1" hole / carbon steel EAM-705-0 Adapters
Single-blade 90°, 130 mm / 1.4571 EAL-707-1 Mounting plate, 1½" hole / 1.4571 EAM-706-0 1" BSP
–
1½" BSP/1.4571 EA
A
-601-0
3-blade extended, 268 mm / 1.4571 (1) EAL-708-1 Mounting plate, 1½" hole / carbon
steel EAM-707-0 1" BSP – 1½" NPT/1.4571 EAA-602-0
3-blade standard, 120 mm / 1.4571 (1) EAL-709-1 Mounting plate seal EAM-704-0M-003 1½" BSP
–
2" BSP/1.4571 EA
A
-603-0
Mounting sleeve (3x20) 4cesp3x20ykoy 1½" BSP
–
3" BSP/1.4571 EA
A
-609-0
1½" BSP
–
1¼" NPT/1.4571 EKH-402-1M-000-01
1½" BSP
–
2" NPT/1.4571 EKN-402-1M-000-02
(1) With a mounting plate (2) Coding of length in accordance with the “Insertion Length” column of the Order Code table.
2.5. DIMENSIONS
2.5.1 UNITS
STANDARD VERSION ROD EXTENDED VERSION
Single-blade paddle EL–, EK–02–3-blade paddle ELF–, EKF–02–Single-blade paddle ELR–, EKR––
Insertion length (L): 0.3 – 3.0 m (1 – 10 ft)
CABLE EXTENDED VERSION WITH COUNTERWEIGHT HIGH-TEMPERATURE VERSION
Single-blade paddle EKK–, ELK––3-blade paddle EKL–, ELL––EM–, EH–7–
Standard 1 or 3-blade paddle, rod or cable version

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2.5.2 ACCESSORIES
Single-blade curved paddle
(168 mm, 6.6 inches)
EAL–701–1
2-blade flexible paddle
(172 mm, 6.8 inches)
EAL–703–1
Single-blade 90° paddle
(130 mm, 5.1 inches)
EAL–707–1
Inserted through a 1",
45 mm (1.75 inches)
long process
connection.
Default blade, for most
applications
Can be inserted even through a
1", 90 mm (3.5 inches) long
process connection.
Paddle cannot be used with
sticky materials, as they may
prevent the blades from closing
when removing.
The blades must be closed by
pressing the blade tips together
when the unit is installed.
Inserted through a 1½", 50 mm
(2 inches) long process
connection.
For light materials due to its large
blade.
Single-blade curved paddle
(120 mm, 4.7 inches)
EAL–701–1
2-blade flexible paddle (120 mm, 4.7 inches)
EAL–704–1
Rigid pipe for cable extended version
EAK–7–1
Inserted through a 1",
45 mm (1.75 inches)
long process
connection.
For coarse or sticky
materials. The material
stuck to the blade tends
to affect the operation
of the unit less.
More robust due to the
blade’s small area and
insertion length.
Can be inserted even through a
1", 90 mm (3.5 inches) long
process connection.
Paddle cannot be used with
sticky materials, as they may
prevent the blades from closing
when removing.
The blades must be closed by
pressing the blade tips together
when the unit is installed.
For materials with a larger
specific weight.
By pulling it over the cable rope,
it makes units with cable rope
extension stiffer.
Caution! If the cable rope is
shortened, the tube must be cut
to a matching length.
The length of the exposed cable
rope section must be at least 30
mm (1.2 inches).
Single-blade straight paddle
(170 mm, 6.7 inches)
EAL–705–1
3- blade extended paddle (268 mm, 10.5 inches)
EAL–708–1
Pipe extension Ø10x1
EAR–70–1
Inserted through a 1½"
process connection.
For coarse or sticky
materials. The material
stuck to the blade tends
to affect the operation
of the unit less.
Use a mounting plate to insert
paddle into the tank!
Primarily for light materials due
to its large blade.
Extended variant.
The extension can only be used
with a top-mounted standard
model.
It is crucial it the paddle of pipe-
extended models is not exposed
to strong lateral forces, for they
may damage the pipe!
If the required “L” length is
different than the one in the order
code, it must be specified.
Single-blade straight paddle
(70 mm, 2.75 inches)
EAL–706–1
3-blade standard paddle (120 mm, 4.7 inches)
EAL–709–1
Mounting plate
EAM–70–0
Inserted through a 1½"
process connection.
For dense materials.
More robust due to the
blade’s small area and
insertion length.
Use a mounting plate to insert
paddle into the tank!
Primarily for light materials due
to its large blade.
Stainless steel and carbon
steel variant available. The
latter is electrostatic powder-
coated to prevent rusting.
Sliding sleeve for rod extended version
EAM-703-0
Flexible Coupling
EAS-701-0

Only for the ER-7 variant,
for changing the insertion length

To protect the paddle from
strong dynamical effects that
may occur during operation.

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3. INSTALLATION
The device can be installed in several ways, depending on the design (vertical, horizontal, angle), with threaded connections, mounting plates, adapters, adjusting units,
etc. The unit must be protected against steady material influx by selecting the appropriate mounting position or using an overhead protective shield. When the device is
mounted onto the side of the tank, coning or arching of the material must be taken into consideration. The preferred location for the unit is the one with the least amount of
vibration. It is important that the device is installed so that the cable glands are in the correct position.
If the device is mounted onto the side of the tank, deposits may clog the connection point and block the movement of the paddle; therefore, they must be prevented.
If a 3-blade unit is on a mounting plate, the insertion hole must be at least 110 mm (4.3 inches) for the paddle to pass safely. Do not forget to use the mounting plate
seal! When mounted on a bracket or mounting plate, a 1" or 1½" flat nut can be ordered to fasten the unit. Mounting plates thinner than 9 mm (0.35 inches) requires
spacers. Attaching rod extensions longer than 0.5 m (20 inches) to the tank wall is recommended. For upper-level switching, using a standard model with the appropriate
paddle between the process connection and the measured medium standard is recommended, and if necessary, it must be equipped with a flexible coupling or a rod
extension to reach the required detection level. When using the unit for low fail-safe indication, it is necessary to install a deflector element. A cable-extended version
recommended for low-level switching, with a suitably-sized rigid tube, if necessary. A rigid tube is recommended if the measured medium forms a steep cone or the
surface is so rigid that the paddle cannot penetrate the material, and the level tends to deviate significantly from its vertical position. If so, it is recommended to use a rigid
tube for proper operation.
Besides, there are countless ways to use the device, but you should always be careful about choosing the right process connection and protection of the device.
Protection with a protective shield Connection for mounting plate (recommended)
Side mounting Mounting
Correct
Correct
Incorrect
Incorrect
In case of side-mounted units, the cable glands should face down!
4. MOUNTING
The paddle must be fixed to the device by inserting the two attached pins before
the installation. When using a mounting plate, it must be mounted first, followed
by the paddle. The cable of cable-extended units can be secured the same way
as the pins.
To customize the cable extension’s length, cut the cable starting from the lower
end. First, remove the grub screws from the lower cable holder. Then cut the
cable to the required length. It is recommended to wrap adhesive tape around
the wires of the cable when cutting to prevent them from fanning out. After
cutting the cable, the holder must be assembled with the probe. If a rigid tube is
attached to the unit, it must be cut for the appropriate length before re-
assembling!
Modifying the insertion length of an extended rod version is possible with the
optional sliding sleeve. It needs a 1½" BSP / NPT nozzle. The BSPT thread can
be screwed into a suitable BSP or an NPT threaded nozzle with a hex neck
(SW55 size wrench for 1½"), and the single-blade paddle can be passed through
the hole.

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5. WIRING
EK
–
, EH
–

–
 devices:
EL–, EM–– devices:
6. OPERATION
The device must be connected to the protective earth with its internal or external
grounding screw! After energizing the supply terminals, the unit is fully
operational.
-If the paddle is rotating freely (not immersed in the medium), the status
LED is green. When the medium reaches the paddle and stops it from
rotating, the output microswitch changes its state, the motor stops, and
the status LED turns red.
-If the LED of the device is blinking, the supply voltage is too low for the
device to operate (EL–, EM––4M, –8M devices).
To adjust the sensitivity of EK–, EH–– devices, the following
must be considered:
The spring provides reliable operation with mediums of different densities. The
default state of the sensitivity adjustment of the spring is position 1. This setting
is suitable for almost all applications. However, if the medium is wet, sticky, and
prone to form deposits on the paddle, it alters the sensitivity of the device
substantially, especially in horizontal or inclined positions. By adjusting the
spring tension (SENSITIVITY 1–4), the sensitivity of the device can be adjusted
to the desired level. Remember to clean the device regularly.
The sensitivity of EL–, EM–– devices can be adjusted by
loosening the SWITCHING FORCE adjustment screw, moving the sensitivity
adjustment spring, then retightening the switching force screw.
The purpose of the switching force screw is to ensure the proper operation with
a great variety of materials. The default setting for the screw is the weakest.
This setting may be used for all applications. However, if the medium is wet,
sticky, and prone to form deposits on the paddle, it alters the sensitivity of the
device substantially, especially in horizontal or inclined positions. By adjusting
the SWITCHING FORCE, the sensitivity of the device can be adjusted better to
suit the application, device variant, and medium.
When the medium’s density or the grain size is not appropriate for the number of
blades, the medium may not be able to stop the rotation of the paddle.
Therefore, the output switch will not change its state despite the medium
reaching the paddle. By choosing the right paddle type and SENSITIVITY
settings and SWITCHING FORCE according to the density of the medium,
reliable switching can be ensured in most cases. A custom-sized paddle is
required for very low-density materials.
Remember to clean the paddle regularly and occasionally the housing as
well!
Operation Status
Power Supply Status LED Paddle Output
ON* Green Rotates NC
Red Does not rotate NO
OFF Dark Does not rotate NC**
*EL–, EM––4M, –8M devices indicate low supply voltages by blinking the LED!
** The output of EK–, EH–– devices are not defined!
7. SPECIAL CONDITIONS OF EXPLOSION-PROOF USE
The housing cover may only be removed only in a de-energized state
and only after the necessary waiting time
(BKI11ATEX0026X Test certificate point 15.5)
The power supply and the output terminals may only be connected to
electrical circuits with short-circuit protection.
8. MAINTENANCE, REPAIR
The device does not require regular maintenance. In some instances, however,
the unit may need occasional cleaning to remove material deposits. All repairs
during or beyond the warranty period must be carried out at the manufacturer’s
premises.
9. STORAGE
Ambient temperature: -30 °C … +60 °C (-22 °F … +140 °F)
Relative humidity: maximum 98%
eka7021a0600h_06
January 2021
NIVELCO reserves the right to change technical specifications
without notice.