Installation & Operation Manual Continuous Level Indicator

Installation & Operation Manual

Continuous Level Indicator

NIVOMETER MLC 830/831/832

Manufactured by

Nivo Controls Pvt. Ltd. 104 – 115 Electronic Complex

Indore 452003. INDIA

i

MLC 830

Safety Guidelines All the precautions and warning notices as mentioned in the manual

must be strictly followed to ensure personal safety and to protect the product and the other connected devices.

Qualified Personnel

This instrument should be operated and used strictly in accordance with this manual. Only a technically qualified person with basic knowledge regarding electrical practices is authorized to install and operate the instrument.

Disclaimer In order to continuously improve quality, Nivo Controls Pvt. Ltd. reserves the right to modify the technical data without prior notice. Responsibility as to the suitability and intended use of the instrument rests solely with the operator. Improper installation or operation of the instrument may result in loss of warranty.

MLC 830

ii

Contents 1 Application 1

2 Symbols 1

3 System Description 1

4 Installation Guidelines 5

5 Wiring 6

6 Calibration 7

7 Maintenance 9

8 Troubleshooting 9

9 Technical Data 11

10 Operating Principle 12

11 Appendix 13

12 Warranty 18

09/MKT/217/V0

MLC 830

1

1 Application These capacitance instruments are ideally suited for continuous

measurement of liquids and slurries of homogeneous compositions having a Stable dielectric constant. The performance of these instruments is not affected by the properties of the material such as conductivity, corrosiveness and viscosity.

2

Symbols The following symbols may have been used on the instrument or in the documentation. They should be interpreted as described below.

Symbol Description

Indicates Direct Current

Indicates Alternating Current

Earth (Ground) Terminal

Protective Conductor Terminal This terminal should be connected to ground.

Indicates an action or procedure which, if not performed correctly can result in either personal injury or incorrect operation of the device. Comply strictly with these instructions.

Risk of electric shock

3

System Description The Probe

The complete instrument consists of a Sensor and a Transmitter. 1. The Probe 2. The Preamplifier S-11 3. The Nivometer MLC

.

The probe is the active element of the system that goes within the container from top and comes in contact with the material whose level is to be measured.

The filling material may or may not be electrically conductive .It is important to select the correct probe for material in each case, keeping into consideration the size, aggressiveness, abrasion, buildup tendencies and other characteristics of the material. Fully insulated probe (rod or rope) is used for continuous level measurement. For mounting these probes (vertically) bush or flange construction is given .A cast aluminium housing (head) is provided at the top of the probe for mounting the Preamplifier S-11.

2

MLC 830

The Preamplifier S-11:

The Preamplifier circuit converts the change in capacitance, which results due to change in material level inside the container, into level proportional DC signal. The level proportional signal is transmitted to Nivometer MLC for further processing. The Preamplifier circuit is mounted on a glass epoxy board. The glass epoxy board is then encased in plastic housing and is filled with synthetic potting resin. Potting this circuit protects It against the influence of dust, moisture and vibration.

The Nivometer MLC:

The level proportional signal from Preamplifier S-11 is evaluated in the

Nivometer. The Nivometer also provided the DC supply voltage for the Preamplifier S-11.it house the transformer, DC power supply and the control unit.

Standardized signal of 4-20mA is available at the output of the Nivometer for

remote display. The material level is also indicated by the built in digital display. Potentiometers for adjusting 0% and the 100% level are accessible on removing the front panel.

Nivometer available in following two versions.

NIVOMETER MLC

Nivometer MLC 830/831/832 with Rod Probe

Probe Rod ~Ø12

Preamplifier Housing

Probe Rod ~Ø12Cable for SensorConnection


Pre-Amplifier1 2 3 4 5 6

Probe Hsg. Green Wire

MLC 830

S11Sr. No. O/F No.

NC

+

NC

InputInput

LEDNIVOMETER

%

7 Segement Display

CurrentOutput4-20 mA

Power SupplyRated Voltage 230V AC ORRated Voltage 24V DC

`` Remote- In Remote Version electronics and probe are interconnected using a cable supplied with the instrument.

MLC 830

3

Mounting Bush

Cable Gland

Insulation

Current Output4-20 mA

Power SupplyRated Voltage 230V AC ORRated Voltage 24V DC

Probe Rod ~Ø12

NIVOMETER

%

Housing Top View

LED

7 Segement Display

Electronics(Nivometer+Preamplifier)

NIVOMETER MLC


Compact- In compact Version electronics and probe form a single mechanical entity.

4

MLC 830

The Nivometer MLC Available Models

1. Nivometer MLC 830 - Indicator:

Indicates the material level by built in 7 Segment Digital Display and gives 4-20mA output.

2. Nivometer MLC 831 - One Set Point: Functions same as MLC 830-Indicator and gives alarm if material level

above or below the selected alarm level depending upon selection of fail safe mode Maximum or Minimum respectively.

3. Nivometer MLC 832 - Pump Control: Functions same as MLC 830-Indicator along with an additional facility of

maintaining material level between two levels, low and high (Pump Control). It indicates level alarm condition only for one level, either low or high depending on selection of fail safe mode Maximum or Minimum.

Fail Safe Mode

Depending on the process requirement, Maximum fail safe mode or Minimum fail safe mode can be selected in Nivometer.

1. Maximum fail safe mode means that the relay de-energizes when the level exceeds the desired level (Probe Covered) or when mains supply fails.

2. Minimum fail safe means that the relay de-energizes when the level

drops below the desired level (Probe Uncovered) or mains supply fails. As relay de-energized condition is used for alarm condition, so apart from level alarm condition, even in case of instrument failure or power failure, the operator gets an alarm. This results in better reliability of operation.

Factors Influence Measurement Accuracy

1. The distance between the probe and the container wall should be

constant throughout the probe length. 2. High viscous material will have a tendency to stick to the probe. This will

influence to some extent to the 0% level setting.

MLC 830

5

3 Installation

Ensure that the mains supply is switched off during installation

Please refer figures in Appendix for some installation tips.

• Fully insulated Probe (rod or rope type) with mounting bush or flange is mounted in a container vertically from top.

• Probe should be firmly fixed on a vibration free foundation. • During installation rotate the mounting bush of the instrument not the

housing. • Select the mounting location such that during filling of the container

the material does not fall directly on the probe. Otherwise use protection shown in Appendix.

• For container having irregular shape or which are filled with the liquid having low dielectric constant, or strong agitator foam formation, rod probe with ground tube should be used or probe should be mounted on a standpipe.

• When probe is mounted in a concrete container, the metal rod grid in the RCC should be electrically connected to the ground terminal at the probe head.

• For non-conductive container, a counter electrode (300mm wide strip) made from conductive material should be fixed.

• With high bulk temperatures, there should be a heat shield between the vessel and the housing of the instrument.

Preamplifier S-11

The preamplifier is mounted in protective cast aluminium housing on the top of the probe by means of a single screw. The preamplifier consists of a semi-conductor dvice, which limits the working temperature at the Probe head about80˚C. In case, the temperature at the Probe head exceeds the above limit, thePreamplifier is mounted in a separate weather proof housing and connected tothe Probe

Nivometer MLC

Nivometer in Cast aluminium housing can be directly installed in the field. While installing the cable ducts provided with rubber seal should be always point downwards to prevent dust and moisture entry into the instrument. Also take care to protect the instrument from direct sunlight by providing sunshield. Special attention should be paid not to install Nivometer on support and walls, which are being continuously or periodically exposed to heavy vibrations. If this is unavoidable, install the instrument on the rubber cushioning to protect it from direct surges.

6

MLC 830

4 Wiring The following procedure should be carried out for wiring the instrument.

Rotate the top cover of the housing to loosen and remove it. Hold housing base while opening and closing the cover.

Unscrew the flap and move aside. Remove the display module Connect the instrument as per the wiring diagram give below.

Connection Diagram for Separate Version

Sensor S-11

56 4 3 2 1

7643 521+ - E

Mains Relay

119 108

- +

Sensor

Power Supply24V DC ±10%(24V DC Rated Voltage)

C NO NC 20mA

4mA

CurrentO/P

Sensor S-11

56 4 3 2 1

7643 521L N E

Mains Relay

119 108

- +

Sensor

Power Supply85 to 265V AC, 50 Hz(Rated Voltage 230V AC)

C NO NC 20mA

4mA

CurrentO/P

NIVOMETER MLC Terminals NIVOMETER MLC Terminals

Connection Diagram for Compact Version

7643 521L N E

Mains Relay

119 108

- +

Sensor


C NO NC 20mA

4mA

CurrentO/P

Internally Connected(Factory Setting)

NIVOMETER MLC Terminals

7643 521+ - E

Mains Relay

119 108

- +

Sensor

Power Supply24V DC ±10%(Rated Voltage 24V DC )

C NO NC 20mA

4mA

CurrentO/P

Internally Connected(Factory Setting)


Note- • In Compact Version Sensor S-11 internally connected to Nivometer. • Relay output is available only for Nivometer MLC-831/832.

MLC 830

7

5 Calibration

Ci C

Close

Open

Field SettingDIP Switch (For Range Selection C)Closing Switch : Range Closing Switch : Range Closing Switch : Range *(Closing Switch one at a time)

*

Field SettingDIP Switch (For Selecting Intial Capacitance C )Open Switch : Range Closing Switch : Range

i

Nivometer MLC 830 To calibrate the MLC 830 following procedure should be followed:

a) Connect the Preamplifier S-11 to the Nivometer terminals as per the

connection diagram b) Connect the mains power supply. c) Fill the vessel upto 0% level (i.e. the minimum level from which material is

to be measured.) d) Select the initial capacitance range І (Ci) by opening the DIP Switch І. e) Adjust 0% on display by turning the 0% potentiometer. f) If not adjustable, then select next initial capacitance range П by closing the

DIP Switch І. g) Repeat step (e). h) Fill the vessel upto 100% level (i.e. the maximum level upto which material

is to be measured.) i) Select the range І (∆C) by closing the DIP Switch П. . j) Adjust 100% on display by turning the 100% potentiometer. k) If 100% not adjusted then first open the DIP Switch П, then close DIP

Switch Ш for selecting range П, repeat step (j). Again if 100% not adjustable then first open DIP Switch Ш, then close DIP Switch ІV for selecting capacitance range ІV, repeat step (j)

l) Check the calibration once again by emptying the tank to 0% level and filling upto 100% level.

m) The output will vary corresponding to 0 %( 4mA) and 100% (20mA) level of the material being measured.

Nivometer MLC 831

To calibrate the MLC 831 following procedure should be followed:

a) Connect the Preamplifier S-11 to the Nivometer terminals as per the connection diagram.

b) Connect the mains supply. c) Select the required fail safe mode using jumper JP1. d) Keep the switch SW1 at “ALARM” position. Set the required alarm level

with the help of HL set POT, at this instance the display shows the alarm set value.

e) Fill the vessel upto 0% level (i.e. the minimum level from which the material is to be measured.)

f) Select the initial capacitance range І (Ci) by opening the DIP Switch І. g) Adjust 0% on display by turning 0% potentiometer. h) If 0% not adjustable then select the initial capacitance П (Ci) by closing

DIP Switch І. i) Repeat step (g.) j) Fill the vessel upto 100% level (i.e. the maximum level upto which the

material is to be measured.) k) Select the range І (∆C) by closing the DIP Switch П.

Close one DIP Switch at a time.

8

MLC 830

l) Adjust 100% on display by turning 100% potentiometer. m) If 100% not adjusted then first open the DIP Switch П, then close

DIP Switch Ш for selecting range П, repeat step (l). Again if 100% not adjustable then first open DIP Switch Ш, then close DIP Switch ІV for selecting capacitance range Ш, repeat step (l)

n) Check the calibration by once again emptying the tank to 0% and filling upto 100% level.

o) The output will vary corresponding to 0 %( 4mA) and 100% (20mA) level of the material being measured. Check alarm set value.


Switch SW1 should be at Normal position for normal Operation.

Nivometer MLC 832

To calibrate the MLC 832 following procedure should be followed:

a) Connect the Preamplifier S-11 to the Nivometer terminals as per the connection diagram.

b) Connect the mains supply. c) Select the required fail safe mode using jumper JP1. d) Rotate the LL potentiometer fully anticlockwise direction. e) Keep the Toggle Switch SW1 at “ALARM” position and set switch

SW2 to HL position .set the required high level alarm with the help of HL: set POT, at this instance the display shows high level alarm value.

f) Now toggle Switch SW2 to LL position and set the low level alarm by LL set POT, at this instance display shows low level alarm value.

g) Now toggle Switch SW1 to normal position and SW2 to HL position.

h) Fill the vessel upto 0% level (i.e. the minimum level from which material is to be measured.)

i) Select the initial capacitance range І (Ci) by opening the DIP Switch І.

j) Adjust 0% on display by turning the 0% potentiometer. k) If not adjustable, then select next initial capacitance range П by

closing the DIP Switch І. l) Repeat step (j). m) Fill the vessel upto 100% level (i.e. the maximum level upto which

material is to be measured.) n) Select the range І (∆C) by opening the DIP Switch П. o) Adjust 100% on display by turning the 100% potentiometer. p) If 100% not adjusted then first open the DIP Switch П, then close

DIP Switch Ш for selecting range П, repeat step (o). Again if 100% not adjustable then first open DIP Switch Ш, and then close DIP Switch ІV for selecting capacitance range Ш, repeat step (o).


q) Check the calibration by once again emptying the tank upto 0% level and filling upto 100% level. Check alarm set values.

r) The output will vary corresponding to 0% (4mA) and 100% (20mA) level of the material being measured..

Switch SW1 should be at Normal position for normal Operation.

The Instrument will show negative display if the level is below 0% or the level is above 199%.

MLC 830

9

6

Maintenance

Never attempt to loosen or remove the process connections or instrument housing while the process is under pressure.

7

The electronic part of the instrument needs no maintenance, as there are no moving parts. In case, the sensor requires cleaning due to deposited material, periodically clean the sensor taking care not to scratch or press the surface of the transducer. Ensure that the cable glands and the housing lid are sealed to prevent the ingress of dust and moisture.

Troubleshooting General Checks: • If the system does not function properly, then check that Nivometer

is properly connected. • There is true earth connection to the container and Preamplifier • Preamplifier is properly tightened in probe housing and free from any

deposition.

Checking of Probe

The Preamplifier must be removed from the Probe Head. When the Probe is uncovered an infinitely high ohmic resistance must be present between the earth of Probe head and Probe connection. Résistance value which can be measured indicate a faulty Probe.

Remove Preamplifier from the Probe head. Keep it connected electrically with Nivometer. Instead of a Probe, Connect a capacitance decade (10-4500 pF) between Probe connection and earth terminal (6) to stimulate material level. Operating Voltage

18V DC between Preamplifier terminal 3 (+) & 4(-) operating voltage too small or absent indicates

1) Nivometer Defective or 2) Current consumption of Preamplifier is

high

Checking of Preamplifier S-11

Current Consumption 5mA between Preamplifier terminal 3 and Nivometer Terminal 11.

Sensor S-11

56 4 3 2 1

7


643 521L N E

Mains Relay

119 108

- +

Sensor


C NO NC 20mA

4mA

CurrentO/P

10

MLC 830

Sensor S-11

56 4 3 2 1

7


643 521+ - E

Mains Relay

119 108

- +

Sensor

Power Supply24V DC ±10%(24V DC Rated Voltage)

C NO NC 20mA

4mA

CurrentO/P

Hf Voltage

11Vpp /33 KHz between Probe connection point and ground terminal (6) of Preamplifier Hf voltage to small or absent indicates either Preamplifier is defective or Probe is defective.

Signal Current

Measure between Preamplifier Terminal (1) and Nivometer terminal (9) depend on capacitance. Signal current should vary linearly with change in capacitance value when capacitance changed between probe connection point and earth terminal (6) of Preamplifier

Checking of Nivometer

Measure the following voltages on Analog PCB. +18V±5% = At IC Z3’s Pin 8 W.r.t. Pin4.

+18V±5% = At IC Z5’s Pin 8 W.r.t. Pin4

-12V±20% = At IC Z10’s Pin 2 W.r.t. TP4

Measures the following Test point voltages with respect to GND (Test Point TP4) on Analog PCB.

+5V±5% = At TP1

-5V±5% = At TP2

+15V±20% = At TP3

+1±0.005V = At TP5 (when level is 100%)

0 ± 0.005V = At TP5 (when level is 00%)

Check level proportional current output at terminal 7 and terminal 8 of Analog PCB. When level is 100% current output is 20mA and when level is 00% current output is 4mA. Note- See Appendix for PCB Layouts.

MLC 830

11

8

Technical Data

Initial Capacitance

1) 30 to 65 pF 2) 60 to 280 pF

Capacitance Variation

1) 10 to 100 pF 2) 70 to 500 pF 3) 450 to 4500pF

Indication

1) 0 to 100% (On a 2-½ digit 7 segments LED Display.) 2) Bicolour LED

• Red LED for Alarm. (MLC-831/832) • Green LED for Normal. (MLC-831/832)

Output

1) 4-20 mA (Optically Isolated) with Max. Load resistance 600E. 2) One set of potential free changeover contact rated 3A at 230V AC for non inductive load. (Only for MLC-831/832)

System Accuracy ±2 %

Instrument Accuracy ±0.5 %

Relay Status 1) De-energized in Power Fail or Alarm Condition. 2) Energized in Normal Condition.

Fail Safe Mode

Maximum/Minimum (Field Adjustable) (Selectable for MLC-831/832)

Mains Supply

• 85-265VAC, 50Hz(Rated Voltage 230V AC) or • 24V DC ± 10% (Rated Voltage 24V DC)

Cable Entry M16 Cable Glands (3 Nos.) suitable for Dia. 4.5

mm to 10 mm. Option- ½ ” NPT 2Nos.

Power 7W (Max.)

Housing Material: Cast Aluminium Paint: Polyurethane 2K

Protection

IP67

Operating Temperature

0-60 °C

12

MLC 830

9 Operating Principle

The Capacitance measuring system works on the principle of change in capacitance (∆C). The capacitance of parallel plate capacitor is..

1) Directly proportional to the cross sectional area of plate ‘A’. 2) Inversely proportional to the distance ‘D’ between them. 3) Directly proportional to the dielectric constant of insulating material

Єr.

In Actual practice, Probe (Rod or Rope) and container wall form two plates of the capacitor. When the container is empty, the dielectric medium separating the two plates is air with dielectric constant approximately equal to 1. when the container is filled with the material , air displaced by the material having dielectric constant greater than 1,which thereby results in a increase of the capacitance. This increase of capacitance is directly proportional to change in material level provided:

1. Material’s dielectric constant remains unchanged. 2. Distance between Probe and container wall is same over the entire

measuring range. therefore, for a continuous level measurement, it is very important that

dielectric constant of the filling material does not change with time. Otherwise, error in measurement will take place.

Dielectric constant of the material can change, when there is a change in chemical composition of the liquid whose level is to be measured.

MLC 830

13

10 Appendix Probe Installation

Drawbacks 1. Probe mounted close to container wall. 2. Subject to sunlight.

Drawbacks: 1. Probe to close to container wall. 2. Subject to sunlight. 3. Material inflow directed on rope Probe.

• Weight will touch container wall. • Probe and insulation will get damaged soon.

14

MLC 830

Dimensional Drawing Remote Version of Nivometer MLC-830/831/832

Power SupplyRated Voltage 230V ACORRated Voltage 24V DC

Flange (optional)


Ø84

112" BSP

93


Cable Gland

Mounting Bush

Insulation

Min

. 300

Max

. 350

0

±10 ±0

.5

±0.5

ControllerHousing

Cable Gland

Mounting BracketCarbon Steel

LEDNIVOMETER

%

7 Segement Display

155x155

116.

5

Probe

Ø6.5x4 Nos.

Controller

Ø84

112" BSP

93


Cable Gland

Mounting Bush

Insulation

Min

. 300

Max

. 350

0

±10 ±0

.5

±0.5

ControllerHousing

Cable Gland


12

Probe Rod ~Ø12

25

Pro

be L

engt

h

Ø125Ø125

Input

105

116.5


12

Probe Rod ~Ø12

25

Pro

be L

engt

h

Ø125Ø125

Input

Cable for SensorConnection

105

116.5

155x155

116.

5

Probe

Ø6.5x4 Nos.

Controller

Note: All dimensions are in mm. unless otherwise specified.


Ø6.5x4 Nos.

Controller

Ø84

112" BSP

93


Cable Gland

Mounting Bush

±0.5

±0.5

ControllerHousing

Cable Gland


25

Ø125Ø125

Input

Cable for SensorConnection

105

116.5

155x155

116.

5

Probe

%

7 Segement Display



Flange (optional)

Nivometer MLC 830/831/832 with Rope Probe

Pro

be L

engt

h Wire Rope Ø3

Max

. 100

00

Min

. 300

Weight

Ø38

76

+20

25

Ø125Ø125

Input

105

116.5

155x155

116.

5

Probe

Ø6.5x4 Nos.

Controller

Ø84

112" BSP

93


Cable Gland

Mounting Bush

±0.5

±0.5

ControllerHousing

Cable Gland


LEDNIVOMETER

MLC 830

15

Pro

be L

engt

h

112" BSP

Mounting Bush

Controller Housing25

Cable Gland

Min

. 100

Max

. 350

0

Insulation

155

Ø125



±10

180

12

Probe Rod ~Ø12

NIVOMETER

%


Housing Top View

Flange (Optional)


LED

7 Segement Display



NIVOMETER

%

Housing Top View

LED

7 Segement Display

112" BSP

Mounting Bush

Controller Housing

25

Cable Gland

Ø125

180

Pro

be L

engt

h Wire Rope Ø3

Max

. 100

00

Min

. 300

Weight

Ø38

76

+20

Flange (optional)


Nivometer MLC 830/831/832 with Rope Probe

155

Dimensional Drawing Compact Version of Nivometer MLC-830/831/832

16

MLC 830

PCB Layouts Component Layout of MLC- 830/831/832

F1

CN1

CN2

Power Supply PCB

OPEN

1 2 3 4 Ci C

MIN MAX

VR7

DIPSW

LED

NORMAL

ALARM

SW1 SW2 HL

LL

VR1VR6

VR2VR5

0%ADJ

HLSET

LLSET100%

ADJ

JP1

*

Display PCB Note-Don’t disturb setting of * marked components.

MLC 830

17

Component Layout of MLC 830 Analog PCB

CN6 CN7

E N L

NCNOCENL +4mA

20mAE-+

CN4

Analog PCB

Z10

VR8

TP4

TP2

VR4

VR3*

*

*

TP3

Z5

Z3

TP1

VR9*TP5

TP6

Note-Don’t disturb setting of * marked components.

18

MLC 830

Warranty Standard guarantee is for twelve months from the date of commissioning or eighteen months from the date of dispatch which ever is earlier. Guarantee term is strictly for any manufacturing fault i.e. any defect in material or workmanship. We undertake to make good the defect at our own expense, provided notice is given to us as soon as it is discovered and the instrument is forwarded to our factory insured and freight paid and with seals unbroken. Our responsibility is limited to the cost of removing the defect in the instrument itself.

Customer Service

Nivo Controls Pvt. Ltd. 104 – 115 Electronic Complex Pardesipura Indore – 452010 India Phone: +91 731 2553248 / 49 Fax: +91 731 2550075 Url: www.nivocontrols.com Email: [email protected]

Installation & Operation Manual Continuous Level Indicator

Documents

Transcript of Installation & Operation Manual Continuous Level Indicator