Being the driving force behind most factory, manufacturing, mining machinery, heavy vehicles and equipment, pneumatics are a vital part of our industry today. The field of pneumatics is vast and knowledge is constantly requested in the workings and troubleshooting thereof.

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How to calculate power in an inductive load?

Inductive load power is reactive, it is given by the formula:


in time domain (instant power);


in Laplace transform domain (RMS denotes root mean square amplitude).

VL is the voltage across the inductor L and IL is its current (current enters in the "+" voltage reference pin, by applying user convention in which absorbed power is positive).

Power is reactive since voltage and current are always in quadrature:

VL(s) = s L IL(s),

in Laplace domain (derived from the time-domain formula vL(t)= L diL(t)/dt).

A real-life inductor will also show an active power term, which arises from parasitic resistance non-ideality; it can be modeled as a resistance DCR in series with the inductor itself:

pACT(t)=DCR IL(t)


An inductive load such as an induction motor draws power from the supply with a power factor of less than 1.

Power = voltage x current x power factor.

This happens because the current reaches its peak in the ac cycle after the voltage, so that for a small part of the cycle power flows back into the supply from energy stored in the motor's internal magnetic field. The time-lag is measured in degrees and called the phase difference. 360 degrees denotes one complete cycle.

The power factor is the cosine of the phase difference, so that (for example) a resistive load has no phase difference so that the power factor is 1, while for a pure inductor the phase difference is 90 degrees and the power factor is zero.

If the rms voltage and current are expressed in complex-number form, also known as vectors or phasors, the real power is the real part of VI*, where the asterisk denotes the complex conjugate.

Another way to calculate the real power is to calculate the average value of the instantaneous power V x I. If the voltage is Vcos(wt) and the current is Icos(wt+phi) then those expressions can be multiplied together and trigonometry formulas used to show that the power factor is cos(phi) as stated.

Real power is measured from the average value of volts times amps with an instrument that contains a voltage coil and a current coil. The force produced is equal to the instantaneous power, and the instrument measures its average value muliplied by the time.

Fuel and Engines
Mechanical Engineering

What is the maximum temperature produced in diesel engine during cycle?


Electrical Engineering
Electrical Wiring
Machinery and Tools

What is the basic function of a megger?

A Megger is a device that will test the insulation of the circuit it is connected to. It produces a DC voltage to check for leakage current from the conductor to ground. It then will give you the value of insulation in Mega Ohms. Generally anything less than one Mega Ohm per thousand volts is poor insulation. Be careful when using this device because it does produce high DC voltages and it can give you an awakening jolt. It is most commonly used to test the insulation in motors and generators but can be used in many other applications.

Note that the word "Megger" is actually a trade name (hence capital M). The generic name for such an insturment is "high-voltage insulation tester".

Although Mega Ohms is strictly correct, you'll most often hear it pronounced rather more easily as "Meggohms".

Mechanical Engineering

What is a steam hose?

A steam hose is a hose used for moving and directing steam.

Combustion Engines
Aerospace Engineering

What are static load and dynamic load?

A static load is the effect of gravity on an object or structure.

A dynamic load is the forces that move or change when acting on a structure.

Example of a dynamic load:

Force of wind or the weight of a truck

Example of a static load:

Weight of a bridge

Mechanical Engineering

How do you decide when to use pneumatic or hydraulic power?

If the low-and high speed needed to be the squamous cell system is used. If the power and speed needed to be at least the hydraulic system is used.

Mechanical Engineering

What is a pneumatic system?

A system that uses air to power something. For instance, have you seen the tube systems at bank drive-up tellers? Air is used to push the tubes back and forth from the teller to the customer. Air is also used to power drills, sanders, grinders, and the like at garages and car body shops. Additionally, you can find pneumatic systems in large buildings or complexes. They're used there to control the air handling systems, the HVAC. Control systems decide which system valves to actuate and they are operated by pneumatics.

Workers Compensation
Industrial Engineering
Mechanical Engineering

Disadvantages of pneumatic system?

  • High noise levels
  • Oxidation that causes blockages
  • System could be fragile and easy to damage
  • High maintenance
  • Entire system goes down if air supply shuts down.

What is electro-pneumatic control?

The pneumatic system controlled by electronic systems.

Mechanical Engineering

Is Hydraulics More Effective Then Pneumatics?

My thoughts go like this...(from watching 'Scrapheap Challenge"0 plus a little basic knowledge of physics.

1/ Pneumatics involve the movement of pistons and what not via the medium of compressed air or air under pressure.

2/ Hydraulics involve the movement of pistons and what not via the medium of compressed fluids or fluid under pressure.

3/ Fluid is denser than gas (compressed air).

I believe hydraulics can handle far heavier loads than pneumatics.

Pneumatics would appear to use a lighter more flexible medium than hydraulics.

In answer to your question, I believe hydraulics would be far more effective at manipulating heavy loads versus pneumatics.

However, pneumatics would be a more flexible system than hydraulics.

Hows that?

Mechanical Engineering

What is an example of a sentence with pneumatic?

Pneumatic is a type of gas!

Civil Engineering
Mechanical Engineering

1 bar equals how many psi?

1 bar = 14.50377438972831 PSI

Mechanical Engineering

What are the advantages of pneumatics?

pnematics works on air and hence it is readily available in the atmosphere.

implies no need of any special storage tank.

it is low in cost than its counterpart the hydraulics.

it is much more compact than hydraulics.

it is very suitable for power transmission when distance of transmission becomes higher than mechanical and lower than the electrcal.

it gives better contol over other transmission sources such as the mechanical and the electrical.

Mechanical Engineering

How hydraulic and pneumatic used in daily life?

hydralics are used in car brakes,space ships,air planes,heavy equipment,lifts.

Mechanical Engineering
Welding and Cutting

What are the welding parameters that must be considered to produce quality weld?

the metals to be welded should be placed correctly, the dust on the metals should be removed, the distance between the metals and electrode should be maintained, proper current must be produced on the basis of metal thickness.

Mechanical Engineering

Why is oil not water used in hydraulic jacks?

Among other reasons, oil is a natural lubricant, it doesn't evaporate readily, and it doesn't support corrosion.

Oil has a much larger temperature range in which it stays a liquid.


What is pneumatics and how does it work?

In a nutshell, pneumatics is a means whereby signals and energy are transmitted, controlled and distributed using pressurized air as the medium. Pneumatics can be effectively combined with other technologies through the use of sensors, transducers and microprocessors

Small Business and Entrepreneurship

What is pneumatic hooter?

Pneumatic hooter is basically for audible alarm in hazardous area location, being used with intrinsically safe alarm annunciators.

Computer Hardware

What are the safety precautions for a laboratory?

First of all, pay attention to what you are doing and what you are working with.

Always wear safety glasses or goggles when working with dangerous chemicals.

Know where the laboratory safety equipment is located.

Tell the instructor of any accidents immediately.

Keep food and drinks out of the laboratory work area.

When dealing with chemicals, always read labels carefully to be absolutely certain that you have the right chemical.

Sometimes you will be told to use a certain concentration of a solution. In those cases, be sure you check the label for concentration as well as the name of the chemical.

Never mix chemicals that you haven't been told to mix without an "okay" from the instructor.

If you spill a chemical, wipe it up immediately andadvise the instructor. Be sure to let the instructor know what you have spilled.

If you get any chemical on you, rinse it off immediately with lots of water and let the instructor know what you spilled on your way to rinsing it off.

Consumer Electronics
Chemical Engineering

What is the working principle of pneumatic transmeter?

I think your are asking about the working principle of a pneumatic transmitter. (not transmeter) A pneumatic transmitter measures liquds or air temperatures over a given range-usually a 200 degree temperature range. The range, selected for its purpose could be -40 to +160 or 0 to 200 -as in the case of Honeywell or even 100 deg. ranges, as in the case of say-Johnson Controls. (0-100) Aside from temperature range, the other important criteria is the output of the transmitter. In the case of commercial controls, the correlation of 200 degree temperatures (which is 201 values, not 200) occurs over a pressure span/output of 3 to 15 pounds.(13 values) For example, in the case of a 200 degree transmitter of say 0 to 200 degrees, the zero temperature value output equates to a 3 psi signal. At 200 degrees, the top of the range, the transmitter would output a 15 psi signal. In other words every degree change up from zero degrees would account for a pressure increase (rounded)of .064 psi. (13 pounds divided by 201 degrees)=.0646766) Pneumatic transmitters are typically direct acting and are one-pipe constant bleed devices. Their working principle involves movement of a flapper a given distance in direct response to the sensed temperature acting upon it. As the temperature rises, the bleed port positions itself toward a closed position which allows less air to escape to atmosphere. Less air to atmosphere dictates more air building up in the air line. This value is then transmitted/measured by the controller-which is pneumatically attached to the transmitter.


What is the working principle of pneumatic thermostat?

A pneumatic thermostat is one that controls the air handling system by using an air-filled control tube to send signals. Pneumatic thermostats typically use a bi-metallic strip that responds to temperature changes, and correspondingly increases or decreases the air pressure in the control tube. Separate components within the air handling system respond to the pressure changes in the control tube to activate heating or cooling to occur through the ductwork.


What psi is considered a high pressure pneumatic system?

factory air pressure norm is 80 psi

Mechanical Engineering

How are the pneumatic system and the hydraulic system similar?

pneumatics use gases such as air or nitrogen,hydraulics use oil or water,both systems use pressure to act on a specific application

History of Science

How are pneumatic and hydraulic systems different?

the main difference between hydraulic and pneumatic system is that hydraulics uses fluid to power their system and pneumatic uses air (in that case air is not a fluid)

All matter is made up with all particles.

thanks you can see more answer in this web i put these all answer.

Mechanical Engineering

Why would you use hydraulic power instead of pneumatic?

One instance would be when space is a criteria, on an aircraft for instance.


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