Gelec DLLC7000 User manual

User’s & Technical Manual – DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000
GELEC Industrial Electronics PAGE 1
DIFFERENTIAL LIQUID LEVEL CONTROLLER
DLLC7000
INDUSTRIAL ELECTRONICS

User’s & Technical Manual – DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000
GELEC Industrial Electronics PAGE 2
CONTENTS
1. PRECAUTIONS!.....................................................................................................................................................................................3
2. MANUFACTURER’S WARRANTY, GENERAL TERMS AND CONDITIONS.......................................................................4
3. DISPOSAL OF OLD ELECTRICAL & ELECTRONIC EQUIPMENT..........................................................................................5
4. DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000.......................................................................................................5
5. GENERAL DESCRIPTION...................................................................................................................................................................6
6. DLLC7000 VERSIONS.........................................................................................................................................................................7
7. DLLC7000 OVERVIEW & CONFIGURATION .............................................................................................................................7
8. PNEUMATIC SECTION.......................................................................................................................................................................9
9. INSTALLATION .................................................................................................................................................................................. 12
10. ELECTRICAL SECTION..................................................................................................................................................................... 15
11. OPERATING PHILOSOPHY –LEVEL DESCRIPTION.............................................................................................................. 17
12. LEVEL CALIBRATION PROCESS................................................................................................................................................... 20
13. FILLING / DRAINING OPERATING MODES ............................................................................................................................ 21
14. DIMENSIONS ..................................................................................................................................................................................... 23
15. TECHNICAL SPECIFICATIONS...................................................................................................................................................... 24

User’s & Technical Manual – DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000
GELEC Industrial Electronics PAGE 3
1. PRECAUTIONS!
There are no serviceable parts inside the DLLC7000 unit. Not to be opened by any
unauthorized person. All repairs to the device must be carried out by the manufacturer.
Improper handling may result in serious personal injury and considerable material
damage. All connection and maintenance work must be carried out by qualified personnel.
RISK OF ELECTRIC SHOCK!
Use the correct voltage. The DLLC7000 is designed for use
with specific voltage only. Connection to a different voltage
may cause fire, electric shock or other damage.
Do not touch the plug and the connectors with wet hands.
Disconnect the DLLC7000 before cleaning it, to avoid the risk of electric shock.
Attempting to use a malfunctioning DLLC7000 can be dangerous.
Do not block the ventilation slots of the DLLC7000 enclosure.
Keep liquids away from the DLLC7000.
Spillage into the enclosure may result to fire, electric shock, or equipment damage. If a
small object or liquid falls/spills into the DLLC7000 cabinet, unplug the unit immediately.
Have the unit checked by a qualified service engineer before using it again.
Set the DLLC7000 in an appropriate location.
Do not install in a dusty, humid, or vibrating environment. Do not place it near heater, or air
conditioner. Keep it away from air, steam, extremely high or low temperature or humidity.
Always follow the instructions given by Gelec and use the DLLC7000
in accordance to its specifications.

User’s & Technical Manual – DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000
GELEC Industrial Electronics PAGE 4
2. MANUFACTURER’S WARRANTY, GENERAL TERMS AND CONDITIONS
Thank you for purchasing our product.
Our products have been manufactured with the latest technology, the highest quality
components and have gone through rigorous quality control tests at the factory, before
shipment. Make sure that the part number and type indicated in the identification label and
pack correspond to the part number or type of your order. After receiving, inspect the unit
to ensure that no damage have been caused during transportation.
GELEC and GELEC’s authorized distributors warrant to the original purchaser that the
product shall be free from defect in material and/or workmanship. The warranty period
begins on the purchase date (proof of purchase by invoice or delivery note) and is valid for
one (1) year.
In the event of malfunction during the warranty period attributable directly to faulty
material and/or faulty construction and functional defects, GELEC and authorized
distributors will, at their option, either repair or replace the faulty product with the same or
similar model.
GELEC and authorized distributors shall have no obligation under this warranty, however, in
the following cases:
Any defect caused by freight damage, accident, disaster, faulty maintenance or
improper handling.
Any defect caused by modification, alteration, abuse, misuse or incorrect installation.
Any defect of the product caused by improper repair by third party other than GELEC
and GELEC's authorized distributors.
Any incompatibility of the products with subsequent technical innovations or
regulations.
Any defect of the product caused by external equipment.
Any defect of the product on which the original manufacturer’s labeling has been
altered or removed.
In case of complaint, please contact our company or send the unit un-dismantled to your
local dealer. Any necessary replacement parts and necessary repair work are totally covered
free of charge.
All products are designed and produced by GELEC to be in compliance with the EU norms
applying to them. GELEC is not responsible for direct or indirect damages or malfunction
caused by improper use or installation of the DLLC7000.

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GELEC Industrial Electronics PAGE 5
3. DISPOSAL OF OLD ELECTRICAL & ELECTRONIC EQUIPMENT
This symbol, found on your product, indicates that this should not be
treated as household waste when you wish to dispose it.
It should be handed over to an applicable collection point for the
recycling of electrical and electronic equipment.
By ensuring this product is disposed of correctly, you will prevent
potential negative consequences to the environment and human
health, which could otherwise be caused by inappropriate disposal of this product.
The recycling of materials will help to preserve natural resources.
4. DIFFERENTIAL LIQUID LEVEL CONTROLLER DLLC7000
This operator's manual explains the functions and operation of the DLLC7000. It also gives
some troubleshooting tips as well as general precautions to be taken when operating the
unit. In order to ensure the best performance and effective use of the DLLC7000, we
recommend that you read the information in this manual carefully and follow the
instructions contained.
This manual is a complete guide for the DLLC7000 with information on unit user
maintenance, unit installation and operational instructions. Do not touch parts of the
DLLC7000 that are not referred in this manual. Keep this manual for immediate reference. It
should help in solving any operational questions you may have.
No part of this manual may be quoted, reproduced, stored in a retrieval system,
transmitted, transcribed or translated into any other language in any form or by any means,
electronic, mechanical, or otherwise, without prior written permission of Gelec.
Although every effort has been made to ensure that this manual provides up to date
information, please note that the contents of this manual and unit specifications are subject
to change without notice.
Don’t forget to mention the exact type and
version of your DLLC7000 whenever you contact
the manufacturer, asking for any further
information. You can find this information on
the identification label of the unit.

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GELEC Industrial Electronics PAGE 6
5. GENERAL DESCRIPTION
The DLLC7000 is a programmable, rangeable device used for liquid level control within a
desirable region, in open tanks of height from 10cm up to 500cm, with analog sensor and
digital output. Its operation is based on the measurement of liquid’s hydrostatic pressure.
The system requires the installation of a bubble tube submerged in the measured fluid,
properly connected to the device with pneumatic tubes. A volume of compressed air is
constantly released into the fluid in a form of bubbles through the device’s airflow regulator
and the bubble tube.
As the level changes, the backpressure measured by the device’s gauge pressure sensor is a
direct level measurement. Several electronic circuits and a microcontroller process this
signal and depending on user adjustments, a digital command occurs when the tank liquid
reaches the selected Target Level. The outcome is the fluctuation of the level within a
desirable working region (between Target Level and Differential Level).
MAIN FEATURES
Precise measurement and level control in open tanks
Programmable selection of FILLING/DRAINING operating mode
Level control in tanks with foam and variety of liquids (acidic, alkaline etc.)
Control in open tanks without the danger of sensor damage from falling water
Principle suitable for tanks with danger of explosion
Programmable selection of High, Low, Target and Differential critical levels
Incorporated airflow regulator with pneumatic adaptors for 6/4 tubes
On-board knob for the Target Level tuning.
Thermoplastic housing (Polyamide PA 6.6) proper for DIN NS32/NS35 mounting
Customized versions available
12-36 VDC / 10-30 VAC / 0,5 W

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GELEC Industrial Electronics PAGE 7
6. DLLC7000 VERSIONS
DLLC7000 VERSIONS
DLLC7000 is provided in two versions with different pressure sensors, in order to meet a
wide range of level measurement application needs.
DLLC7000-S1
DLLC7000-S5
Operating pressure range
0-10 kPa (1.45 psi)
0-50 kPa (7.25 psi)
Factory calibrated level range (H2O) (1)
0-100 cm
0-500 cm
Sensor resolution (H2O)
0.97 mm
4.88 mm
1) Factory calibration has been made with water in ambient temperature. Values may differ when the
device is recalibrated under each application’s specific conditions and measured fluid.
7. DLLC7000 OVERVIEW & CONFIGURATION
The DLLC7000 is a complete unit with 6 built-in connection terminals, an air flow regulator
with pneumatic adaptors, adjusting level knobs, a function button and a status LED. Its
thermoplastic housing (Polyamide PA 6.6) is approved for electronic devices in industrial
environment. It is designed to be installed inside a vented electrical control panel, snapped
onto commercially available DIN mounting rails (NS32/NS35).
STATUS LED
The STATUS LED at the front side indicates various operational
stages and the operating mode of the DLLC7000. Consult the
following table for quick reference and the relevant sections for
detailed information.
LED COLOR
DLLC7000 STATUS
OFF
Device not powered
RED
Device powered - Normal operation
GREEN
Relay contact activated
FLASHING GREEN
High Level calibration (check calibration section)
FLASHING RED
Low Level calibration (check calibration section)
FLASHING ORANGE
Differential Level calibration (check calibration section)
INITIAL POWER SUPPLY
Flashing RED
DRAINING MODE
Flashing GREEN
FILLING MODE
Alternating RED/GREEN
During operating mode selection F/D)

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GELEC Industrial Electronics PAGE 8
FUNCTION/CALIBRATION BUTTON
The Function/Calibration button is used during calibration process
and operating mode selection (FILLNG/DRAINING). Refer to the
relevant sections in this manual for more information.
ON-BOARD POTENTIOMETER (KNOB)
The potentiometer’s position, adjusts the liquid’s Target level (TL)
into the tank. Notice that the 0-100 scale refers to the percentage
of the High Level (HL). Therefore, the value that the arrow is
pointing, is the desirable (TL), but as a percentage of the (HL) and
not as an absolute value. The potentiometer’s use during the level
calibration process is described in the corresponding section.
AIR FLOW REGULATOR
The one-way air flow regulator controls the volume of air which
escapes the bubble tube. Having the recommended pneumatic
layout, you will find this airflow rate preset at approximately 3-4
bubbles per second. This is the recommended rate for a
controlled and constant stream of bubbles, which is important for consistent measurement.
The airflow adjustment can affect the device’s proper functionality and re-adjustments are
not recommended by a user which is not familiar with the device operation. However, if it is
necessary adjust the regulator with a flat screwdriver (clockwise for decreasing,
counterclockwise for increasing) and set the bubbles to the recommended rate. The front
label may block the regulator access, for unintended adjustments protection.

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8. PNEUMATIC SECTION
GAUGE PRESSURE SENSOR
DLLC7000 includes a gauge type, silicon piezoresistive pressure sensor, providing an
accurate and linear output directly proportional to the applied pressure. On-Chip
Temperature Compensated & Calibrated, this sensor is laser trimmed for precise Span,
Offset calibration and temperature compensation.
Having a gauge pressure sensor, the DLLC7000 uses the atmospheric pressure as a
reference. This means that it must be installed in a vented electronic panel in order to have
the same pressure conditions with the measured tank, which is open/vented by default.
PNEUMATIC ADAPTORS
DLLC7000 has three straight male pneumatic adaptors for 6/4 connection tubes.
The (P) adaptor is the input of the internal air flow regulator and is used for the
compressed air supply. Provide an invariable pressure, higher than the hydrostatic pressure
of the tank. A recommended pressure value would be approximately 1.5 bar (22 psi).
The (O) adaptor is the output of the internal air flow regulator towards the bubble tube.
Refer to the ‘Airflow Regulator’ section in this manual, for bubble adjustment information.
The (S) adaptor is the input of the internal pressure sensor which measures the hydrostatic
pressure. Check the pressure limits of your DLLC7000 version before any connection.
Excessive applied pressure can cause permanent damage, or degradation to the sensor.
The (O) and (S) adaptors need to be externally connected with an ‘Y’ pipe connector.

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GELEC Industrial Electronics PAGE 10
BUBBLE TUBE
A thin tube should be firmly installed in the tank with its nozzle
submerged in the measured fluid. A small volume of air is
provided to this tube through the device’s air flow regulator and
connection pipes, escaping into the liquid in a form of bubbles.
The device measures the hydrostatic pressure at the point
where the bubbles are released.
At the bottom side, the tube’s nozzle must have a smoothed V-
notch, in order to assist the release of a controlled and constant
stream of small bubbles (3-4 per second). This is preferable for
consistent measurement, rather than intermittent large bubbles.
On the top side, a pneumatic fitting is needed to connect the
6/4mm tube which lead to (S)/(O) adaptors of the DLLC7000.
Use standard and compatible pneumatic parts, which meet the
operating requirements of the application regarding pressure,
temperature, safety etc.
The top of the tube must be at least 25cm above the fluid’s
highest possible level, for avoiding fluid suction towards
connection tubes and DLLC7000 after air supply cut-off.
In order to have unaffected measurement, it is very important
to prevent air leakage in all pneumatic connections. Use
an appropriate thread sealant in all threaded elements.
In a common level measurement application, the tube is installed almost at the bottom of
the tank. Ensure that the provided air can escape freely into the fluid and the nozzle is
not blocked by the tank body or possible sediment/dirt during operation. Partial blockage
of the nozzle will cause faulty readings and full blockage will lead the compressed air
supply directly to the pressure sensor and damage it.
Don’t install the tube deeper than your DLLC7000 version allows. The excessive applied
pressure can cause permanent damage or degradation to the device’s pressure sensor.

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GELEC Industrial Electronics PAGE 11
CONNECTION TUBES
The adaptors are suitable for 6/4mm tubes and the supported types are PA6, PA11, PA12,
Polyurethane, Polyethylene, PTFE and FEP. Ensure that the tubes meet the operating
requirements of your application (pressure, temperature, safety etc.).
To assembly, insert the tube on the nut, thread the tube on the fitting cone and tighten the
nut by hand, or with a spanner.
Ensure that pipes are smoothly curved and not bended at all points. Piping layout should
remain sufficiently protected from possible bending, blockage, tear, corrosion, or any
damage that would affect the device’s functionality.
Maintain the pneumatic circuit in good condition. Polluted air, dust, oil etc. inside the
circuit may gradually affect the measurement, clog up the pipes, or even damage the
device’s pressure sensor.
Any air leakage along the (O/S) piping will affect the measurement.

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9. INSTALLATION
In this section, you can find useful information that have to be taken under consideration
during DLLC7000 installation. Always follow the recommended instructions and use the
DLLC7000 in accordance to its specifications.
INSTALLATION AREA
Having a gauge pressure sensor, the DLLC7000
uses the atmospheric pressure as a reference. This
means that it must be installed in an electronic
panel under atmospheric pressure, in order to be
under the same pressure with the measured tank,
which is open/vented by default. Keep the unit
protected from steam, flame, extremely high or low
temperature and humidity. Do not block the
ventilation slots above and below the unit. Fluid
insertion into housing may cause damage, electric
shock or fire.
In the back side of DLLC7000, there is a clip for the mechanical mounting (lock) on an Ω-
type mounting rail (DIN NS32/NS35), with the release hook at the bottom. The device
should have at least 60mm free space below it for the air pipes and 15mm on top of it, for
the wires. Ensure that the connected pneumatic tubes are smoothly curved and not
bended.
PNEUMATIC CIRCUIT
Pneumatic layout must be sufficiently protected from possible bending, blockage, tear,
corrosion, or any damage that would affect the device’s functionality. Polluted air, dust, oil
etc. inside the circuit may gradually affect the measurement, clog up the pipes, or even
damage the device’s pressure sensor. Check the pneumatic circuit periodically and
clean/replace the pipes if necessary. Use standard and compatible pneumatic parts, which
meet the requirements of the application regarding pressure, temperature, safety etc.
In order to prevent fluid suction towards piping and DLLC7000 after air supply cut-off,
the top side of the bubble tube must be at least 25cm above the fluid’s highest level.
Additionally, you can install the device at a point higher than your tank. If somehow fluid
suction occurs, disconnect the (O/S) tube from DLLC7000, clean it and confirm that the
device works properly before using it again.

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BUBBLE TUBE - APPLICATION TANK
The measured level corresponds to the upright distance between the bubble tube’s
V-notch vertex and the fluid level. For example, in a common application this point is
usually the bottom of the tank.
After the tube installation, confirm that bubbles are released from the V-notch and not
from another point of the nozzle. The provided air volume must escape freely into fluid,
with the nozzle not being blocked by the tank body, or possible sediment/dirt. Partial
blockage may cause faulty readings and full blockage will lead the air supply directly to the
sensor and damage it. In case of tanks with sediments, install the tube at a higher point (so
the bubble stream is not affected) and consider this elevation as an offset.
With an invariable pressure of 1.5 bar, possible bubble discontinuance doesn’t mean airflow
adjustment malfunction. It may be caused by blockage, or air leakage along piping. Inspect
(O/S) adaptors and piping for possible damages.
Even if the bubble tube is not submerged into fluid, long distance tubing or other factors
in installation may rise a small amount of pressure to the sensor, causing a small output
offset. Re-calibrating Low Level will solve the issue, refer to the relevant section.
DLLC7000 has a gauge pressure sensor which uses the atmospheric pressure as a reference.
Therefore, the application tank must be open or vented and the measured fluid
constantly under atmospheric pressure.
Pneumatic Layout example

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GELEC Industrial Electronics PAGE 14
APPLICATION FLUID
The application fluid must be homogenous, having the same density at all points of its
volume and with relatively low viscosity, in order to allow a controlled and constant stream
of bubbles through it. For example, honey is not an appropriate fluid for this measuring
method. In addition, the fluid cannot be sensitive to a gas bubbling through it.
DLLC7000 standard versions are factory calibrated with water in ambient temperature,
exploiting the whole operating pressure range of their pressure sensor (1m of water in
DLLC000-S1 / 5m of water in DLLC7000-S5), unless otherwise stated on the product label.
So, the level which generates the maximum output signal corresponds to the maximum
pressure that your version can handle.

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10. ELECTRICAL SECTION
ELECTRICAL CONNECTIONS
The DLLC7000 housing is equipped with 6 connection terminals, two triple screw terminal
blocks per side (top & bottom).
The terminal blocks are manufactured to provide resistance to stress corrosion cracking,
electrolytic corrosion, rusting and screw loosening in case of vibrations. This way, conductor
connections are maintained reliable and maintenance-free in harsh industrial environment.
The conductor’s stripping length should be 8 mm, with its cross-section within the
following ranges (depending on type). The recommended tightening torque is 0.5 - 0,6 Nm.
Clamp all types of copper cables without pre-treatment. Do not solder the conductors, as it
affects the proper connection quality. Two conductors with the same cross section make
contact safely in the clamping parts. If necessary, copper ferrules can be used as a
protection against splicing when stranded conductors are wired. In general terms, ensure
that you are having reliable mechanical connection and electrical contact.
CONNECTION TERMINALS
Read carefully the following information and refer to the connection diagrams and technical
data, regarding proper wiring of the DLLC7000 with the associated equipment.
Confirm that you have proper connections before unit operation. Wrong connections may
lead to permanent device or external equipment damage. Don’t proceed to any connection
modification, while the unit is powered.
TERMINALS #4 - #5 (POWER SUPPLY - VPS)
Connect the power supply (12-36 VDC) / (10-30 VAC) to terminals #4 and #5.
Maximum power consumption is approximately 0.5W. There is not an electrical safety fuse
in the internal power circuit. Although the polarity is not important, as the internal power
circuit includes electronic components for non-polarity connection, ensure that you are
applying proper voltage. When the unit is powered, the indicating led turns on.
Rigid solid :
0,2 - 4,0 mm2
Flexible stranded :
0,2 - 2,5 mm2
AWG :
24 - 12

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TERMINALS #1 - #2 - #3 (DIGITAL OUTPUT - #1=N.C. - #2=COM - #3=N.O.)
This output (terminals #1 , #2 , #3)works as a potential contact of a relay. These contacts
allow the operation of the device that fills/drains the tank. The DPDT relay contacts are
potential free (Voltage free common). Make sure not to exceed the relay contact rating.
The relay’s status changes when the tank level exceeds the set point. When this output is
activated the STATUS LED turns green. Any wrong configuration of the relay output
connection, may cause permanent damage to the unit.
TERMINALS #4 - #6 (ANALOG PWM OUTPUT - #4= (-) - #6=0…5V) -Upon request-
--- ONLY when 12-36 VDC is applied to #4 (-) / 5 (+) ---
Through this output (terminals #4 - #6)the device provides a 0-5V signal, which is
proportional to the liquid level height. This voltage is linear and corresponds to the
intermediate tank levels from Low Level (LL=0%) to High level (HL=100%).
In order to get the complete voltage scale (VMAX=5V), the load resistance should be
RL≥1MOhm. If load resistance is smaller than that, VMAX will drop and you should measure
the output voltage value. E.g. for RL=450KΩthe device provides VMAX = 4,5V.
PRIOR CONTACT WITH GELEC IS NECESSARY FOR PWM OUTPUT FEATURE TO BE INCLUDED
DLLC7000 Connection Diagram

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11. OPERATING PHILOSOPHY –LEVEL DESCRIPTION
The DLLC7000 operating philosophy is based on a desirable
working region and four critical liquid levels, which can be
calibrated from the user to meet the application requirements.
These levels and their functionality are described below.
(HL) High Level
It is the highest level the user can select with the potentiometer. You can set this level
following the calibration process.
If the (HL) is modified through the calibration process, the (LL) and the (DL) must also be
modified.
(LL) Low Level
It is the lowest level the user can select with the potentiometer. You can set this level
following the calibration process.
If the (LL) is modified with the calibration process, it is essential for the (DL) also to be
modified to the desirable level.
Working region
It is the desirable region which the liquid level fluctuates, either in FILLING or DRAINING
mode. The working region is between (TL) and (DL), which can also be calibrated.
(TL) Target Level
It is the desirable level and it can be selected by using the potentiometer’s 0..100 scale. At
the (TL), the relay changes status, and the liquid falls back to the Differential Level (DL).
Notice that the 0...100 scale refers to the percentage of the High Level (HL). Therefore, the
value that the arrow is pointing, is the desirable (TL), but as a percentage of the (HL) and
not as an absolute value.
(DL) Differential Level
It is the level which the liquid returns to, after reaching the (TL) and also where the relay
changes its status. (DL) is always lower than the (TL) (pre-selected value 50%(TL)) and the
user can modify it with the calibration process. It is not essential to modify the other levels
after calibrating (DL).

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The user can program the (DL) at a desirable level following the calibration process, without
changing the other two le vel values.
The Differential Level (DL) you select each time, is stored in the unit’s memory as a
percentage of (HL). But during operation, the device uses this factor for the calculation of
the (DL) as percentage of the (TL). So, if the user selects as (DL) the 25% of the (HL), then
the device will function with (DL) = 25% of the (TL).
DIFFERENTIAL LEVEL CALCULATION - EXAMPLE
Use the following procedure and example, as a guide to calculate the differential level you
have to calibrate.
Calculate the differential coefficient (k) between your desirable (TL) and (DL), which are the
two limits of your working region as below:
k = 100 × ( TL – DL ) / TL (1)
And then use k in the following type, to find the liquid level height that you should have
into the tank for the (DL) calibration procedure.
DL = HL - ( HL x k / 100 ) (2)
- OPERATING EXAMPLE -
For example, your application needs the (HL) to be calibrated at 100cm, the (LL) at 0cm
and you want the working region to be between 70cm (DL) and 80cm (TL).
After the calibration of the (HL), (LL), and (TL) you have to calculate the DL before
calibration in accordance with the above types.
In this example the equation (1) becomes:
k = 100 ×( 80-70 ) / 80 = 12.5
And the equation (2) becomes:
DL = 100 - ( 100 × 12.5 / 100 ) = 87,5cm
So, you have to fill your tank with 87,5cm of liquid and then proceed to (DL) calibration.

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When differential level (DL) is calibrated, any target level (TL) selection through the
potentiometer, will lead the device to automatically calculate the working region. At this
example for a (TL) selection of 80cm, the working region will be 80cm-70cm.
Notice that according to the described example’s steps, for every (TL) you select with the
potentiometer, the (DL) will be 12,5% less.
PRESELECTED VALUES
The standard version DLLC7000-S1 can control the liquid level in tanks with height from
10cm to 100cm and has the below preselected values and parameters.
Liquid : Soft Water
High level (HL) : 100 cm
Differential level (DL) : 50% of (TL).
Low level (LL) : 1cm (0+1cm offset)
NOTES
The device measures the hydrostatic pressure of the liquid contained in the tank, so
the tank’s volume and shape are not factors that influence the measurement.
The calibration is done for a specific tank height and for a specific liquid. If you use
the same tank with a different liquid, a new calibration has to be done.
In order to have the optimum measurement resolution, it is recommended the high
level to be calibrated near the target level.
According to your unit version, take care not to exceed the recommended liquid
level height. If the sensor-applied pressure is higher than the appropriate, the sensor
will be destroyed.

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12. LEVEL CALIBRATION PROCESS
With this process, you can calibrate the device to store the required parameters, in order to
function according to your application needs. Follow the appropriate steps for each level
calibration. This can be done either with the on-board potentiometer.
After the device installation, the calibration process as described below is essential. The
correct level calibrating order is (HL) → (LL) → (DL). This order is important in order to get
the optimum level measurement resolution and the on-board knob’s 0...100 scale to
precisely correspond with the levels (LL) - (HL).
If during the calibrating process there is an idle period of 30 seconds, or the power is
interrupted, the device returns in operating mode with the pre-existed values.
(HL) High Level Calibration
•Fill the tank up to the highest desirable level.
•Press and hold the button until the led starts flashing.
•Turn the potentiometer until you find the area where
the led flashes with green color - a sign that the
value to be registered is the High Level (HL).
•Press and hold the button again until the led turns on
constantly.
✓The High Level (HL) value is registered.
If the (HL) is modified through the calibration process, the (LL) and the (DL) must also be
modified.
(LL) Low Level Calibration
•Drain the tank down to the minimum desirable level
•Press and hold the button until the led starts flashing.
•Turn the potentiometer until you find the area where
the led flashes with red color - a sign that the value
to be registered is the Low Level (LL).
•Press and hold the button again until the led turns on
constantly.
✓The Low Level (LL) value is registered.
If the (LL) is modified with the calibration process, it is essential for the (DL) also to be
modified to the desirable level.