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Saturday, September 09, 2017

Coils and Transformers for SMPS

In Switching Power supplies and RF Circuits, the coils and transformers have many types of cores. Ferrites, Powder Iron, Air and others. These are much smaller and lighter for the same power that they deliver, in comparison to the 50/60 Hz Mains Transformers or chokes.

Coils and Transformers for SMPS

CWS - Applications

This section contains useful Application Notes and "How To Use" help to assist engineers better understand various applications of Power Inductors, Common Mode Chokes, Current Transformers, Power Transformers and Ferrites for EMI suppression etc.

Coilcraft - Design Support Tools

Power Magnetics tools, RF Inductor tools, Common Mode Choke Finder, LC Filter Design tool, IC / Inductor Matching tools.

Power Transformer Inductor

In general, ideal SMPS transformers need to transfer all energy instantaneously from one winding to another while storing no or little energy in the process.

Monday, September 04, 2017

Non-Destructive Testing NDT Resource

Eddy Current Testing (ET) and Infrared/Thermal Testing (IRT) are Interesting Areas where experienced designers can build and manufacture Test Equipment.

Community College Education Resource

These pages have NDT study material for college and Science Educational Pages for High School.

Students can get ideas for original project work on one of these concepts. Choose one area and then research in the web. When i had to build Equipment, it would be difficult to get the catalogs and datasheets of Materials or Methods. Now master the art or searching online, then create your database. Study, Learn and Build !

Direct Read Pocket Dosimeter

Direct Read Pocket Dosimeter

"Pocket dosimeters are used to provide the wearer with an immediate reading of his or her exposure to x-rays and gamma rays. As the name implies, they are commonly worn in the pocket. The two types commonly used in industrial radiography are the Direct Read Pocket Dosimeter and the Digital Electronic Dosimeter."

More at - NDT Resource Center

Sunday, September 03, 2017

EMI RFI Mains Power Filters

EMI RFI Noise Filters are required in two situations, to prevent EMI from an Electronic Equipment Like A Dimmer, Thyristor Drive, SMPS or Switcher affecting other Modules in a System or Neighboring Equipment.

The Second Situation is when a Sensitive Equipment Like a Medical Apparatus or Precision Measuring Instrument has to be Immune to any Noise from outside, as it can affect performance.

Sometimes it is Accuracy that can get affected, but some electrical jolts can damage or desensitize fine sensors or positioning systems.

EMI RFI Mains Power Filters

Filters are is connected in series with an Existing Mains Chord. It can also be Fixed in a Control Panel with a Clamp. The two X caps have higher Capacitance Value. The Y cap is Lower Value and withstands around 1kV,  It is better if X cap is AC 440V.

The common mode filter design in such a way that it cancels the noise. The correct winding polarity or direction is important for noise cancellation.

Related Resources

eEngineer - Electrical Engineering, EMI/EMC, RFI -  Introduction to EMI, EMC, RFI, Military EMC Standards, Radio Frequency Interference.

EMI Shielding RF Shielding - Tech-Etch designs and manufactures both standard catalog and customized shielding products.

Dealing with Computer generated RFI/EMI - Most of the time, the RFI generated is enough to render certain bands useless and on other bands, it may drown out any weak signals and distort or interfere with signals that you want.

TDK - Electronic Components & Materials - Electronic devices generate electromagnetic interferences, which can affect the proper functioning of electronic devices and systems

Here is one type i encountered in many T&M Instruments along with TDK too. It was Schaffner - electromagnetic compatibility - International leader in electromagnetic compatibility (EMC) and power quality (PQ). EMC Filters, RFI Suppression Chokes, Feedthrough Components.