NIVELCO NIVOROTA EL-EK-7 Series User manual

eka7021a0600h_07  1 / 5
Thank you for choosing NIVELCO instruments.
We are convinced that you will be satisfied with our product.
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/ EHis mono-directional; in the EL/ EM, 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
paddle or 2-blade paddle with flexible coupling 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: 0.3…3 m (1…10 ft)
Cable extension: 1…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…+120 °C (-4…+248 °F) -20…+80 °C (-4…+176 °F) -20…+200 °C (-4…+392 °F)
Ex variant: see 2.2 Explosion protection data
Ambient temperature -30…+60 °C (-22 °F … +140 °F)
Relative humidity max. 90%
Process pressure max. 3 bar (0.3 MPa, 43.5 psig)
Output SPDT 250 V AC, 6 A, AC1
Paddle-rotation / shutdown
indication Two-toned (green/red) LED
Power supply Nominal value: 230 V AC (50/60 Hz) +10% -15%, 120 V AC (50/60 Hz) +10% -15%
24 V AC (50/60 Hz) +10% -15%, 24 V DC (18…28 V DC) (1)
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 Ø6…Ø12 mm (Ø0.25…Ø0.5 inches) cable
2x 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)
(1) AZ 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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2.2 EXPLOSION PROTECTION DATA
Type STANDARD
EL–, EK–7–5,6,7,8Ex
HIGH-TEMPERATURE
EM–, EH–7–5,6,7,8Ex
Ex marking II 1/2 D Ex ta/tb IIIC T85°C…T135°C Da/Db II 1/2 D Ex ta/tb IIIC T85°C…T200°C Da/Db
Ex power supply
E–7–5Ex: U0≤253 V AC
E–7–6Ex: U0≤132 V AC
E–7–7Ex: U0≤26.4 V AC
E–7–8Ex: U0≤28 V DC
Process and ambient temperature See: “2.2.1 Temperature data for Ex certified models”
Cable entry M20x1.5 cable gland with “Ex ta” certification
Cable outer diameter Ø6…Ø12 mm (Ø0.25…Ø0.5 inches)
Electrical connection Wire cross-section: 0.5…1.5 mm2(AWG20…AWG15)
Ex reference document number eka7021m0600h_07
2.2.1 TEMPERATURE DATA FOR EX CERTIFIED MODELS
Type Temperature class T85°C T100°C T135° T200°C
Standard temperature
EL–, EK–7–5,6,7,8Ex
Maximum surface temperature
60 °C (140 °F) 90 °C (194 °F) 120 °C (248 °F)
–
Maximum medium temperature
Maximum ambient temperature 60 °C (140 °F) 50°C (122 °F)
Waiting time for opening the cover 40 min 30 min 10 min
High temperature
EM–, EH–7–5,6,7,8Ex
Maximum surface temperature 60 °C (140 °F) 90 °C (194 °F) 120 °C (248 °F) 200 °C (392 °F)
Maximum medium temperature
Maximum ambient temperature 60 °C (140 °F)
Waiting time for opening the cover 40 min 30 min 15 min 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, 2 pcs cable gland
2.4 ORDER CODE
NIVOROTA E – – (1)
Version Code Probe version / Paddle /
Process connection Code Housing Code Code Insertion length [m (ft)] Code Power supply / Certificate Code
Standard K
Standard / Single-blade
paddle / 1" BSPT A
A
luminum 7 0 0
(
0
)
0
(
0
)
0 230 V
A
C 1
High-temperature H Plastic (2) 8
1 1 (3.3) 0.1 (0.3) 1 120 V
A
C 2
Standard bidirectional
version L Standard / Single-blade paddle / 1½" BSPT H 2 2 (6.6) 0.2 (0.6) 2 24 V
A
C 3
33 (10) 0.3 (1) 3 24 V DC 4
High-temperature
bidirectional version M Standard / 3- blade paddle / 1½ " BSPT F 0.4 (1.3) 4
230 V AC / Ex ta/tb IIIC (ATEX) 5
0.5 (1.6) 5
120 V AC / Ex ta/tb IIIC (ATEX) 6
With rod extension / Single-
blade paddle / 1½" BSPT R
(1) The order codes of Ex versions end
in ’Ex’ 0.6 (2) 6 24 V AC / Ex ta/tb IIIC (ATEX) 7
0.7 (2.3) 7 24 V DC / Ex ta/tb IIIC (ATEX) 8
With cable extension / Single-
blade paddle / 1½" BSPT K (2) No Ex-version available, no high-
temperature variant available
0.8 (2.6) 8
0.9 (3) 9
With cable extension /
3-blade paddle / 1½" BSPT L
Accessories
Paddles Mounting plate Accessories
Type / material Code Type / material Code Type / material Code
Single-blade curved,
168 mm (6.6 inches) / 1.4571 (316Ti) EAL-701-1 1" female nut / 1.4571 (316Ti) EAM-701-0 Weight / 1.4571 (316Ti) EAW-701-0
Single-blade curved,
120 mm
(
4.7 inches
)
/ 1.4571
(
316Ti
)
EAL-702-1 1½" female nut / 1.4571 (316Ti) EAM-702-0 Flexible Coupling / 1.4571 (316Ti) EAS-701-0
2-blade flexible,
170 mm (6.7 inches) / 1.4571 (316Ti) EAL-703-1 Sliding sleeve for rod extended version / 1.4571 (316Ti) EAM-703-0 Rigid pipe for cable extended version (0.1…3.0 m [0.3…3 ft]) EAK-7-1 (2)
2-blade flexible,
120 mm (4.7 inches) / 1.4571 (316Ti) EAL-704-1 Mounting plate, 1" hole / 1.4571 (316Ti) EAM-704-0 Pipe extension Ø10x1 (0.1…0.5 m [0.3…1.6 ft]) EAR-70-1 (2)
Single-blade straight,
170 mm
(
6.7 inches
)
/ 1.4571
(
316Ti
)
EAL-705-1 Mounting plate, 1" hole / carbon steel EAM-705-0 Adapters
Single-blade straight,
70 mm (2.8 inches) / 1.4571 (316Ti) EAL-706-1 Mounting plate, 1½" hole / 1.4571 (316Ti) EAM-706-0 1" BSP
–
1½" BSP / 1.4571 (316Ti) EA
A
-601-0
1" BSP
–
1½" NPT / 1.4571
(
316Ti
)
EA
A
-602-0
Single-blade 90°,
130 mm (5.1 inches) / 1.4571 (316Ti) EAL-707-1 Mounting plate, 1½" hole / carbon steel EAM-707-0 1½" BSP
–
2" BSP / 1.4571
(
316Ti
)
EA
A
-603-0
1½" BSP
–
3" BSP / 1.4571
(
316Ti
)
EA
A
-609-0
3-blade extended,
268 mm (10.5 inches) / 1.4571 (316Ti)(1) EAL-708-1 Mounting plate seal EAM-704-0M-003 1½" BSP
–
1¼" NPT / 1.4571
(
316Ti
)
EKH-402-1M-000-01
1½" BSP
–
2" NPT / 1.4571
(
316Ti
)
EKN-402-1M-000-02
3-blade standard,
120 mm (4.7 inches) / 1.4571 (316Ti)(1) EAL-709-1
(1) With a mounting plate
Mountin
g
sleeve
(
3x20
)
4cesp3x20
y
ko
y
(2) Coding of length in accordance with the “insertion length” column of the order code table.

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2.5. DIMENSIONS
2.5.1 UNITS
STANDARD VERSION CABLE EXTENDED VERSION WITH COUNTERWEIGHT
Single-blade paddle EL
–
, E
K

–
02
–
3-blade paddle ELF
–
, EKF
–
02
–
Single-blade paddle EK
K
–
, EL
K
–

–
3-blade paddle EKL
–
, ELL
–

–

ROD EXTENDED VERSION HIGH-TEMPERATURE VERSION
Single-blade paddle ELR–, EKR––
Insertion length (L): 0.3…3.0 m (1…10 ft) EM–, EH–7–
Standard 1 or 3-blade paddle, rod or cable
version
2.5.2 ACCESSORIES
Single-blade curved paddle
(168 mm, 6.6 inches)
EAL
–
701
–
1
2-blade flexible paddle
(170 mm, 6.7 inches)
EAL
–
703
–
1
Single-blade straight paddle
(170 mm, 6.7 inches)
EAL
–
705
–
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
Paddle pressure*: 1.4 kPa (0.203 psi)
1" variant, it can be inserted through a 80 mm
(3.15 inches) process connection. The length
of the device must be determined so the
blades can open freely before the threads
meet. Variants with extension pipe or rod are
available.
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 lighter materials.
Paddle pressure*: 0.8 kPa
(
0.116 psi
)
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.
Paddle pressure*: 3 kPa (0.435 psi)

Inserted through a 1½", 50 mm (2 inches) long
process connection.
Shorter insertion length
Fit for most applications
Paddle pressure*: 1.5 kPa (0.216 psi)
Single-blade curved paddle
(120 mm, 4.7 inches)
EAL
–
702
–
1
2-blade flexible paddle
(120 mm, 4.7 inches)
EAL
–
704
–
1
Single-blade straight paddle
(70 mm, 2.75 inches)
EAL
–
706
–
1
3-blade standard paddle
(120 mm, 4.7 inches)
EAL
–
709
–
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.
Paddle pressure*: 10.5 kPa (1.52 psi)
1" variant, it can be inserted through a 80 mm
(3.15 inches) process connection. The length
of the device must be determined so the
blades can open freely before the threads
meet. Variants with extension pipe or rod are
available.
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.
Paddle pressure*: 2.9 kPa
(
0.42 psi
)
Inserted through a 1½" process connection.
For dense materials.
More robust due to the blade’s small area and
insertion length.
Paddle pressure*: 8.7 kPa (1.26 psi)
Use a mounting plate to insert paddle into the
tank!
Primarily for light materials due to its large
blade.
Paddle pressure*: 0.3 kPa (0.044 psi)

4 / 5  eka7021a0600h_07
Pipe extension Ø10x1
EAR
–
70
–
1
Rigid pipe for cable extended version
EA
K
–
7
–
1
3- blade extended paddle (268 mm, 10.5 inches)
EAL
–
708
–
1
Mounting plate
EAM
–
70
–
0
The extension can only be used with a
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.
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).
Use a mounting plate to insert paddle into the
tank!
Primarily for light materials due to its large blade.
Extended variant.
Paddle pressure*: 0,3 kPa
(
0.044 psi
)
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.
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. It must be installed vertically. It will not work correctly if it is slanted or horizontal. 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
Correct
Incorrect
Mounting
Correct
Incorrect
In case of side-mounted units, the cable glands should face
down
!
* The paddle pressure value is understood for 0.2 Nm (0.148 ft-lb) torque in the case of complete
immersion. The specified values are for comparing the paddles. Paddles with lower paddle pressure are
for lighter materials, while paddles with higher paddle pressure are recommended for heavier materials.

eka7021a0600h_07  5 / 5
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.
5. WIRING
EK–, EH–– devices:
EL–, EM–– devices:
6. OPERATION
The device must be connected to the protective grounding 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 SAFE USE
The device housing must be protected against dust!
The housing cover may only be removed only in a de-energized state and
only after the necessary waiting time!
(See: 2.2.1 Temperature data for ex certified models)
The power supply and the output terminals may only be connected to
electrical circuits with short-circuit protection.
The device may only be operated with a power supply specified in 2.2
Explosion Protection Data!
8. MAINTENANCE, REPAIR
The instrument does not require regular maintenance. If necessary possible dirt
deposited should be cleaned off. The warranty conditions are included in the
warranty card.
Before returning the device for repairs, it must be cleaned carefully, the parts in
contact with the medium that might contain harmful substances must be
decontaminated. Our official form (Returned Equipment Handling Form) must be
enclosed. Download it from our website www.nivelco.com. The device must be
sent with a declaration of decontamination. Please provide a statement in the
declaration that the decontamination process is completed, the device is clean and
free from harmful materials, and there are no hazardous substances on it.
9. STORAGE CONDITIONS
Ambient temperature: −30…+60 °C (−22…+140 °F)
Relative humidity: max. 98%
eka7021a0600h_07
April 2021.
NIVELCO reserves the right to change technical data without notice!