Advantages and disadvantages of piezoelectric transducer

When an external force is applied to this transducer, the produced voltage that can be measured easily. This change is measured by its corresponding value of sound or some of the vibration. There are many different types of transducer available but piezoelectric transducer are some of the advantages compare to other transducers. So this page is given below some advantages and disadvantages of the piezoelectric transducer are given below:

 There are some advantages of the piezoelectric transducer which are given below:
  • The piezoelectric transducer has a good frequency response
  • It is small in size
  • It is easy to handle  because of its small dimension
  • It has rugged construction
  • It is available in the desired shape
  • It has a negligible phase shift
  • Natural quartz and barium titanate can be made any desired form and shape
  • It offers high output that is measured in the electronics circuit
There are some disadvantages to the piezoelectric transducer which are given below:
  • It has high-temperature sensitivity
  • Some crystals are water soluble and dissolve in a high humid environment
  • The piezoelectric transducer is used for dynamic measurement only, not suitable for static conditions
  • It needs high piezoelectric cable for electrical interface because the device operates with the small electric charge
  • The output obtained from the piezoelectric transducer is low, so the external electronic circuit has to be connected 
Applications of piezoelectric transducer:
  • It is used in a record player
  • It is used in accelerometer
  • It can be used in electronic watches
  • It is used in spark ignition engines
This article also gives some advantages of piezoelectric pressure transducer which are given below:

Advantages of piezoelectric pressure transducer:
  • Rugged construction 
  • Small size
  • Excellent frequency response
  • High output with negligible phase shift
Disadvantages of piezoelectric pressure transducer:
  • Temperature sensitive
  • It can be used for dynamic measurement only
  • Piezoelectric crystals are water soluble hence it has a high humidity environment gets dissolved
There is some application of piezoelectric pressure transducer which is given below:
  • It is used in spark ignition engines
  • It is used for measurement of nonelectrical quantities such as acceleration, vibration dynamic pressure, and sound intensity
  • It is used in ultrasonic, nondestructive test equipment, ultrasonic flow meters, micromotion actuators

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What is transducer

Definition of transducer:

A transducer is a device that converts the energy from one form to another. Usually, a transducer converts a signal in a form of energy to a signal in another. Some of the transducers is usually more efficient than others, An illustration power into an electromagnetic field. 

Characteristics of the transducer:
One of the main key difference between the sensor and transducer is that the transducer converts the physical quantity or nonelectrical into another signal or electrical signal whereas the sensor senses the physical changes occur in the surrounding.

 The characteristics of the transducer are given below that are determined by examining the output response of a transducer to a variety of input signals. The method of computational and standard statistical can be applied to the test data. 
  • Accuracy
  • Noise 
  • Linearity
  • Sensitivity
  • Hysteresis
  • Size
  • Span 
  • Repeatability
  • Conformance
  • Resolution
  • Speed
  • Ruggedness
  • High output
  • High stability
For detailed information

Different types of transducer:

Classification based on the source of energy: Active and passive transducer 

Classification based on physical quantity: 
  • Pressure transducer - Bourdon gauge
  • Force transducer  - Dynamometer
  • Acceleration transducer  - Accelerometer
The primary and secondary transducer  
For detailed information


 Application of the transducer:

 Application of the transducer in a different part of electronics :
  • Thermistor/ Thermocouple
  • Optocoupler
  • LDR
  • Microphone
  • Hall effect
  • Speaker
  • Magnetic pickup
  • Flame or smoke
  • Pizzo
  • Strain gauge
  • Vibration
  • Magnetism
  • Force
  • Torque
  • Power
  • Current
  • Magnetic flux
  • Position 
  • Humidity
  • Displacement
  • Pressure

For detailed information

Advantages and disadvantages of the electrical transducer:
  • The electrical output of the transducer can be easily used, transmitted and also easily processed for the purpose of measurement.
  • Mass inertia effects are minimized
  • The signal can be conditioned or mixed to obtain any combination with the output of similar transduces or control signals
For detailed information

Transducer

What is a transducer?

A transducer is a device that converts the energy from one form to another. Usually, a transducer converts a signal in a form of energy to a signal in another.


Classification based on the source of energy: Active and passive transducer 

 Classification based on physical quantity: 
  • Pressure transducer - Bourdon gauge
  • Force transducer  - Dynamometer
  • Acceleration transducer  - Accelerometer
Primary and secondary transducer  Read more 

  • Hysteresis
  • Size
  • Span 
  • Repeatability
  • Conformance
  • Resolution
  • Speed
  • Ruggedness
  • High output
  • High stability Read more 


Advantages of electrical transducer:  1. Mass inertia effects are minimized 2. The signal can be conditioned or mixed to obtain any combination with the output of similar transduces or control signals
Disadvantages of electrical transducer: 1. The electrical transducer has costly Read more
  • Thermistor/ Thermocouple
  • Optocoupler
  • LDR
  • Microphone
  • Hall effect
  • Speaker
  • Magnetic pickup
  • Flame or smoke
  • Pizzo
  • Strain gauge
  • Vibration
  • Magnetism
  • Force  Read more 

Microscope vs Telescope

Although both instruments magnify object so that the human eye can see them, the microscope looks at things very near while telescope views things very far away. This difference in purpose explains the substantial differences in their design. Biologists and chemists use microscope ordinarily in laboratories while astronomers use a telescope in observatories.

  • The microscope is used to see a very small object like artificial light whereas a telescope relies on natural light.
  • Where the aperture on a telescope is one of the most important things for viewing planets far in the distance, the opposite is the case for a microscope. Yo don't need a large aperture with a microscope so they tend to have small apertures in comparison to other scopes.
  • In microscope focal length of the eyepiece lens is greater than the focal length of the objective lens while the telescope focal length of the objective is greater than eyepiece.
  • The objective lenses in the telescope areas you might have guessed far larger than the objective lenses in a microscope. In terms of power the objective lens tens to be lower in the telescope.



Difference Between Baseband and Broadband Transmission

Broadband system use modulation techniques to reduce the effect of noise in the environment. Broadband transmission employes multiple channel unidirectional transmission using a combination of phase and amplitude modulation while in baseband is a digital signal is transmitted on the medium using one of the signal codes like NRZ, RZ, Manchester biphase Mcode, etc. is called as a baseband transmission. Here this post gives information about the difference between broadband and baseband transmission to better understand this topic.

Baseband transmission:
  • Digital signaling.
  • Frequency division multiplexing is not possible.
  • The baseband is the bi-directional transmission.
  • The entire bandwidth is for single signal transmission.
  • Short distance signal traveling.
  • Ethernet is using baseband for LAN. 
  • Baseband transmission works well with bus topology. 
  • Manchester and differential Manchester encoding is used for baseband transmissionEntire bandwidth of the cable are consumed by a single signal in a baseband transmission.
Broadband transmission:
  • Analog signaling.
  • Transmission of data is unidirectional.
  • The signal traveling distance is long.
  • Frequency division multiplexing possible.
  • Simultaneous transmission of multiple signals over different frequencies.
  • Used to transmit cable TV to premises.
  • The broadband transmission used with a bus as well as a tree topology.
  • PSK encoding must be used.
  • The signals are sent on multiple frequencies and allow all the multiple signals are sent simultaneously in a broadband transmission.

Transducer characteristics

The characteristics of the transducer are given below that are determined by examining the output response of a transducer to a variety of input signals. The method of computational and standard statistical can be applied to the test data. 

  • Accuracy
  • Noise 
  • Linearity
  • Sensitivity
  • Hysteresis
  • Size
  • Span 
  • Repeatability
  • Conformance
  • Resolution
  • Speed
  • Ruggedness
  • High output
  • High stability

1. Accuracy: It is defined as the closeness which the reading approaches an accepted standard value or ideal value or true value, of the variable being measured.

2. Noise: All transducers have some random noise in their output. So the small signals are largely affected by noise in comparison to larger signals.

3. Linearity: The output of the transducer should be linearity proportional to the input quantity under measurement. It should have linear input-output characteristics.

4. Sensitivity: The electrical transducer is defined as the electrical output obtained per unit in the physical parameter of the input quantity called sensitivity of the transducer.

5. Hysteresis: This property wherein a transducer output is dependent not only on the present input but also on the previous inputs.

6. Size: The transducer should have the smallest possible size and shape with minimal weight and volume. This will make the measurement system very compact. 

7. Repeatability: A transducer ability to produce identical output upon stimulation by the same input in termed as repeatability.

8. Speed: It is rapidity with which the transducer responds to changes in the measured quantity. The speed of the response of the transducer should be as high as practicable.

9. Ruggedness: The transducer should be mechanically rugged to withstand overloads. it should have overload protection.

10. High output: The Transducer should give reasonably high output signal so that it can be easily processed and measured. The output must be much larger than noise. Nowadays digital output is preferred in many applications.

11. Dynamic range: For a transducer, the operating range should be wide so that it can be used over a wide range of measurement conditions.

Different types of transducer

The transducer is used in electronic communication systems to convert signals of different physical forms to an electronic signal. While the sensor is a device that senses a physical quantity and it converts it into an analog type quantity which can be measured electricity such as voltage, capacitance, inductance, and ohmic resistance.

One of the main key difference between the sensor and transducer is that the transducer converts the physical quantity or nonelectrical into another signal or electrical signal whereas the sensor senses the physical changes occur in the surrounding.

Classification based on the source of energy:

The transducer is of many different types of transducer, they can be classified based on various criteria as:
  • Active transducer
  • Passive transducer
1. Active transducer:

In the active transducer, the energy from the input is used as a control signal in the process of transferring energy from the power supply to proportional output. Such type of transducer develops theirs owns voltage or current hence known as a self-generating transducer. This output signal is obtained from the physical input quantity.

Piezoelectric transducer: When an external force is applied to this transducer, the produced voltage that can be measured easily. This change is measured by its corresponding value of sound or vibration.

Piezoelectric transducer applications:
  • This sensor can be used as a knock sensor in automotive engine management systems for noticing knock of the engine
  • This sensor is used for the measurement of pressure and acceleration
  • This transducer is mainly used to detect the sticks drummer impact in electronic drums pads 
Thermopile transducer: The voltage change developed across a junction of two dissimilar metals is knowns by its corresponding value of temperature heat or flow.

Moving coil type: The change in voltage generated in a magnetic field can be measured using its corresponding value of vibration or velocity.

Photovoltaic cell: The voltage change that occurs across the PN junction due to light radiation is known as the corresponding solar cell value or light intensity

2. Passive transducer:

A transducer which requires an external power source for their operation is called a passive transducer. They produce an output signal in the form of some variation in resistance-capacitance or any other electrical parameter like inductance which then has to be converted to an equivalent current or voltage signal. A transducer which requires an external power source for their operation is called a passive transducer.

Resistive transducer:
  • Resistive thermometers
  • Resistive displacement transducer
  • Resistive strain transducer
  • Resistive pressure transducer
  • Resistive moisture transducer
Capacitive transducer:
  • Capacitive displacement transducer
  • Capacitive moisture  transducer
  • Capacitive thickness transducer
  • Inductive displacement transducer
Inductive transducer:
  • Eddy current inductive transducer
  • Moving core inductive transducer

Classification based on physical quantity:

The second classification of the transducer is based on the physical quantity converted. The end use of the transducer after the conversion.

Following some list of transducer based on physical quantity:
Flow transducer - flow meter
  • Pressure transducer - Bourdon gauge
  • Force transducer  - Dynamometer
  • Acceleration transducer  - Accelerometer
  • Temperature transducer  - Thermocouple
  • Displacement transducer  - LVDT

Type of transducer based on the principle of operation:
  • Chemical
  • Mutual induction
  • Photovoltaic
  • Piezoelectric 
  • Hall effect
  • Photoconductor
Primary and secondary transducer:
  • Primary transducer: This transducer consists the mechanical as well as the electrical devices. The mechanical devices of the transducer change the physical input quantities into a mechanical signal or device. This mechanical device is known as the primary transducer.
  • Secondary transducer: The secondary transducer converts the mechanical signal into a form of an electrical signal. The magnitude of the output signal depends on the input mechanical signal.

Advantages of dc chopper

A chopper may be thought of as dc equivalent of an ac transformer so that they behave in an identical manner. As chopper involve that one stage conversion, these are more efficient for the circuit.

Advantages of DC chopper:
  • High efficiency
  • Regeneration
  • Flexibility in control
  • Lightweight
  • Small size
  • Quick response
  • Fast dynamic response
  • Smooth acceleration

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Transducer vs sensor

The transducer is used in electronic communication systems to convert signals of different physical forms to an electronic signal. While the sensor is a device that senses a physical quantity and it converts it into an analog-type quantity which can be measured electricity such as voltage, capacitance, inductance, and ohmic resistance.

One of the main key differences between the sensor and transducer is that the transducer converts the physical quantity or nonelectrical into another signal or electrical signal whereas the sensor senses the physical changes occur in the surrounding.

The main key difference between sensor and transducer are given below:
  • The sensor changes the physical change across the surrounding whereas the transducer transforms the one form of energy into another.
  • The sensor itself is the major component of the sensor whereas the transducer the sensor and the signal conditioning is the major elements of the sensor.
  • The primary function of the transducer converts the physical quantity into an electrical signal while the sensor is to sense the physical changes.
  • The sensor tends to be more sensitive than the transducer.
  • Some transducer can be used as sensors. A transducer converts energy in two directions while a sensor can convert it in one.
  • A transducer converts the measured quantity into a standard electrical signal like -10 to +10V DC while the sensor is used to measure voltage,  capacitance, ohmic resistance.
  • The thermistor and thermocouple are the best examples of the transducer while accelerometer, barometer, gyroscope are the example of the sensors.
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CDMA 2000 forward channel

CDMA 2000 user is assigned a forward channel that consists of the following combination :
  1. Forward fundamental channel  (F-FCH)
  2. 0-7: Forward supplemental code channel (F-SCHs) for both RC1 and RC2
  3. 0-2: Forward supplemental code channel (F-SCHs) for both RC3 and RC
The different forward/downlink physical channel are : 
  1. Forward pilot channel (F-PICH)
  2. Forward auxiliary pilot channel (F-APICH)
  3. Forward transmit diversity pilot channel (F-TDPICH)
  4. Forward sync channel (F-SYNC)
  5. The forward paging channel (F-PCH)
  6. Forward broadcast channel (F-BCH)
  7. The forward quick paging channel (F-QPCH)
  8. The forward common power control channel (F-CPCCH)
  9. Forward supplemental channel (F-SCH)
  10. Forward common assignment channel (F-CACH)
  11. The forward dedicated control channel (F-DCCH)
  12. The forward data traffic channel 
1. Forward pilot channel (F-PICH)
This channel is used to get multipath fading and channel conditions. This channel is shared by mobile nodes to obtain the above mentions information.

2. Forward auxiliary pilot channel (F-APICH)
Every channel is allocated a unique Walsh code under the code-multiplexed method in a downlink.

3. Forward transmit diversity pilot channel (F-TDPICH)
When increased RF capacity this channel is used. In these channels are intended for synchronization by the mobile with a specific cell.

4. Forward sync channel (F-SYNC)
For providing initial synchronization related data to the mobile station this channel is used. 

These are two types of forwarding sync channel that are used :
  • Shared sync channel
  • Wide-band sync channel
5. The forward paging channel (F-PCH)
The base station uses this channel in order to transmit the mobile station specific message and the overhead message. 

These are two types of forwarding paging channel are used :
  • Shared paging channel
  • Wide-band paging channel
6.  Forward broadcast channel (F-BCH)
It is intended to transmit control information to the respective mobile stations effectively that have not been allocated a traffic channel.

7. The forward quick paging channel (F-QPCH)
This quick paging channel is used by the paging channel for providing control information to the mobile stations.

8. The forward common power control channel (F-CPCCH)
The necessary power control information of uplink common control channel is conveyed by base stations using this channel.

9. Forward supplemental channel (F-SCH)
Up to two F-SCHs can be assigned to a single mobile unit for high-speed data ranging from 9.6 to 153.6 kbps in release 0.

10. Forward common assignment channel (F-CACH)
The quick assignment of a reverse common control channel is done by the base station using this channel.

11. Forward common assignment channel (F-CACH)
 It is used to send high layer message to the mobile units. This channel is used by the base station.

12. The forward dedicated control channel (F-DCCH)
  • It replaces the dim and burst and blank and burst
  • It is used for messaging and control for data calls
  • In addition to these channel forward data, a traffic channel is also used in forwarding channels in the CDMA 2000 standard

The minimum configuration consists of a reverse pilot channel to enable the base station (BS) to perform synchronous detection and reverse fundamental channel for voice.

Advantages and disadvantages of electrical transducer

An electrical transducer is one type of device which is capable of converting the physical quantity into a some of proportional to the electrical quantity such as voltage or must be electric current. Hence it covert any quantity to be measured into the usable electrical signal. This post gives the advantages and disadvantages of an electrical transducer to better understand this topic.

Advantages of electrical transducer


  • The power requirement of the transducer is very small. The electrical system can be controlled with a very small level of power
  • Electrical signals can  be easily  attenuated or must be amplified  to the signal and can be brought up to a level suitable for a various device with the help of static device FGK
  • An amplifier may be used for amplifying the electrical signal according to the which types of uses or requirement
  • The electrical output of the transducer can be easily used, transmitted and also easily processed for the purpose of measurement.
  • Mass inertia effects are minimized
  • The signal can be conditioned or mixed to obtain any combination with the output of similar transduces or control signals
  • The data transmission through mechanical mean is eliminated. Thus no mechanical wear and tear and no possibility of mechanical failures exist
  • The reduce effects of friction and other mechanical non-linearities
  • Due to the integrated circuit technology, the electrical and electronic system is compact having less weight and portable
  • The output can be indicated and must be recorded remotely from the sensing element

Disadvantages of the electrical transducer


The electrical transducer is sometimes less reliable than mechanical type because of the aging and drift of the active components. Also, the sensing elements and the associated signal processing circuitry are comparatively more expensive. With the use of better materials, its improved technology, and better for circuitry design, the range of accuracy and stability has been increased for electrical transducer while using negative feedback techniques the accuracy of measurement and the stability of the system are improved but main is that all at the expense of increased circuit complexity more space and obviously more cost.
  • The electrical transducer has costly
  • While designing the circuit the effects of aging and also drifts of parameters of active components must be considered. This makes the design is too much complicated

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Applications of transducer

Application of the transducer is more widely. Some of the used in medicine, such as in sonography machine, While some of the used in music engineering and recording, some of the used in complex mechanical systems and even in safety system like train brakes, Some of the application in different electronics components.  Here this post to cover almost each and every application and uses of the transducer.

Application and uses of the transducer are given below:
  • Transducer measure the load on the engines
  • It is used as a sensor device for knowing the engine knock
  • Measuring inlet, outlet or system pressure in the engine test setup
  • Measuring fluid height or level in tanks
  • Measuring pressure drop in a line for preventive maintenance
  • Sanitary pressure transducer in the bio or pharmaceutical industry
  • Measuring the pressure of slurry or slush using a flush diaphragm pressure transducer
  • It converts the temperature of the devices into an electrical signal or called as  mechanical work
  • It is used for detecting the movement of muscles which is called acceleromyograph
  • The transducer is used in the speaker for converting the electrical signal into acoustic sound
  • It is also used in the ultrasound machine. It receives the sound wave of the patient by emitting their sound waves and pass the signal to the CPU
  • It is used in the antenna for converting the electromagnetic  wave into an electrical signal
  • The transducer measures the pressure  of the gas and liquid by converting it into an electrical signal
  • The classification of the transducer depends on the various factor like by transduction the converting signal from AC or DC, etc
Here this post also gives some common application of transducer in a different part of electronics :
  • Thermistor/ Thermocouple
  • Optocoupler
  • LDR
  • Microphone
  • Hall effect
  • Speaker
  • Magnetic pickup
  • Flame or smoke
  • Pizzo
  • Strain gauge
  • Vibration
  • Magnetism
  • Force
  • Torque
  • Power
  • Current
  • Magnetic flux
  • Position 
  • Humidity
  • Displacement
  • Pressure
  • Velocity
  • Temperature 
  • Pressure
  • Data transfer

Bluetooth range

There are three types of classes in different Bluetooth specification.

Class 1 - Range of fewer than 10 meters
Class 2 - Range of 10 meters (33 feet)
Class 3 - Range of 100 meters (328 feet)

Facts :
  • The range depends on atmospheric, geographic, urban conditions.
  • The range not only depends on the transmitter but also on the mobile phone which is receiving files.
  • The bigger the range, the slower transmission speed.
  • Here above Bluetooth range described above. There are three types of classes. class 1 devices transmit at 1 mW with the range of fewer than 10 meters. Class 2 devices transmit at 2.5 mW with a range of 10 meters or 33 feet. Class 3 devices transmit at 100 mW with the range of 100 meters or 328 feet.

Difference between active transducer and passive transducer

The transducer which generates the output in the form of voltage or current, without any external energy source is known as an active transducer, while in passive transducer means that the like capacitance, resistance, and inductance changes because of the input signal. Here this post we understand the difference between an active transducer and a passive transducer.

The main key difference between an active transducer and a passive transducer given below.

 Difference : 
  • The transducer which gives the electrical output without any external source known as the active transducer while in physical transducer whose physical properties varies because of the input or measured signal known as the passive transducer.
  • The active transducer is also called a self-generating type transducer while the passive transducer is also called an externally powered transducer.
  • The active transducer does not require any additional source while the passive transducer requires the additional energy source.
  • Active transducer does not require any auxiliary power supply, Passive transducer require an auxiliary power supply for transduction.
  • The active transducer, the signal conversion is simpler, while in passive transducer the signal conversion is more complicated.
  • Active transducer the energy to produce output obtained from the physical quantity, while in passive transducer they also derived part of the power required the conversion from physical quantity under measurement.
  • The latest example of the active transducer is bourdon tube, Passive transducer is LVDT.
  • It generated electric current or voltage directly in response to environmental stimulation, while in passive transducer gives a change in some passive electrical quantity, such as capacitance, resistance or inductance as a result of the stimulation.
  • The design of the active transducer is simple as compared to the passive transducer.
  • The resolution of the active transducer is low while that of a passive transducer is high.
  • Active transducer draws energy from the measured source and gives the electrical output while in passive transducer the transduction can be done by changing the physical of the material.

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Transistor advantages and disadvantages

Basically, the transistor is nothing bur solid-state equivalent of a triode valve which was used in radio and early computers. It is made of three-layer semiconductor materials. Common semiconductor two materials in transistor construction are silicon and germanium. It basically acts as an insulator and a conductor. This page almost covers the advantages and disadvantages of the transistor to better understand this topic. 

Advantages of transistor:
  • It is used for fast switching applications
  • Smaller mechanical sensitivity
  • It is used as a current controlled current gain
  • It is available at very low cost
  • It is very smaller in size
  • Fast switching
  • It has a longer lifeLow operating voltage for greater safety, lower costs and  tighter clearances
  • Extremely long life
  • The transistor is very easy to turn ON and turn OFF the power transistor
  • The power transistor can carry large currents in ON state and it blocks very high voltage in OFF state mode
  • ON state voltage drops across power transistor is  very low
  • The power transistor can be operated at switching frequencies in the range of around 10 to 15 KHz
  • There is no power consumption by the cathode heater
  • It uses low voltage for its operation hence it offers more safety
  • It can be used to control the power delivered to the load in inverters and choppers
Disadvantages of transistor:
  • It has reverse blocking capacity is very low
  • It can be damaged due to the thermal runaway or second breakdown
  • Manufacturing techniques are very complex and require a clean room environment
  • Due to its small size, it is difficult to trace out faulty ones due to failure. Moreover, it is very difficult to unsolder and replace new ones
  • Power transistor cannot be operating satisfactorily above switching frequency of  around 15 KHz

Advantages and disadvantages of manometer

The manometer is measured an unknown pressure by balancing in against gravitational force of liquid heads. It can be used to measure dynamic pressures and differential pressures. It can be measure pressure ranging from low to high. Here this page covers the advantages and disadvantages of the manometer  to better understand this topic. 

Advantages of  manometer:
  • It has a low cost
  • The manometer is suitable for low-pressure applications
  • It is simple in construction
  • It has better sensitivity
  • It has good accuracy
  • It has simple operation and construction
  • It does not have to be calibrated against any standard, the pressure difference can be calculated from the first principles
  • The manometer is available for a large range of filling fluids of varying specific gravity
Disadvantages of manometer:
  • It is large in size and bulky
  • It needs leveling
  • No fixed reference is available
  • In manometer, the error is introduced due to condensation
  • It has no over range protection
  • The manometer has a poor dynamic response
  • They have a smaller operating range which is on the order 1000 KN/meter.meter
  • They are fragile and hence offer less portability
  • The manometric fluids density depends on temperature. Hence errors may result due to change in the temperature
  • It has a slow response which makes it unsuitable for measuring fluctuating pressures  
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