Showing posts with label Test-Measurement-2. Show all posts
Showing posts with label Test-Measurement-2. Show all posts

Monday, February 01, 2016

Megger or Insulation Tester

Decades ago, when a customer found that my Tera Ohm Meter expensive, He suggested the specs for this low cost scaled-down model. This was found useful for people sub-contracting Telecom Equipment Manufacturing.

Insulation Tester

Test and Measurement Instruments

This probably went upto 500V and 100V with a Toggle Switch and measured upto 1 Giga Ohm or 1000 Mega Ohms. The test voltage would be applied on the Switch, Connector or Magnetics to measure the leakage current in its insulation. The leakage current would be converted to voltage, clamped with diodes and fed to the Vref of a 7107 which displayed the Insulation Resistance by doing a 1/x. Normally we use Vin to measure the voltage, in this instrument the Vin holds the Reference.

Monday, November 03, 2014

Virtual Oscilloscope - Visualize Equations

Oscilloscope Functions and Fourier Series. Periodic Waveforms. Watch Sine, Square, Triangle and Sawtooth Waves and Study Controls. This Scope is a Real Time Graph of Volts Y and Time X at any node of a circuit. It can show both AC and DC.

Virtual Oscilloscope - Visualize Equations

Load an equation of your own and see it as a waveform on this web scope. Paste a Formula in the Equation text box, load it, it will be rendered as waveform on scope. Learn from this page ....

Virtual Oscilloscope - Visualize Equations

JS Oscilloscope xml code

Just turn it on and then press demo button for 1st Waveform and Press again the demo button for 2nd Wave and so on. Still working on formulas. Slide all the pots and see what happens.

digital-oscilloscope - An Oscilloscope Simulation using CSS and JavaScript

Related Oscilloscope Information

Saturday, September 13, 2014

Analog Dial AVO Amps-Volts-Ohms meter

Many times we cannot carry big or expensive test instruments to the field, so we have to have a troubleshooting tool kit. Continuity testers, Logic Probes, DMM, Clamp Meters etc.. You can troubleshoot and repair Electronic Equipment easily with Meters and Continuity Tester

It also is sometimes required to build a quick jig or fixture with electronics to troubleshoot, simulate a problem or to test the reliability or aging of components and systems. Here you need to be cost effective, fast and innovative; and build a simple system with available, affordable or procurable resources. Hence a bit of circuit design, firmware and software are essential skills for production engineering.

This was designed, keeping in mind, that sometimes we have few components available and we could be flat broke. Even that you could not carry your DMM somewhere, but you have to make some instrument for a quick need with what is available. If you are out of cash or feel like Robinson Crusoe, then this is a low cost measurement system. I designed it to practice on eagle, i am not sure how this circuit may work, it is not tested . But i have built, repaired and designed many DMMs. So there is a fair chance, parts of it may work :~)

IC3 LM555 is to generate -5V from 9V. That reminds me of a story, In 1986 while i was studying BE electronics i got a chance to work part-time in a company that sold-serviced imported instruments, it was called trans-marketing. They were the agents for Racal-Dana, Genrad, Data I/O and so many more. Here i came across a Book called CMOS Hot Ideas of Intersil. I had a chance to observe, build and learn some things here. The ICL7107 circuit was the most fascinating, I also read the books of National Semiconductor here.

Analog Dial AVO Amps-Volts-Ohms meter

In those days small firms used to make DPM's digital panel meters with 7107. In 1987 when i got a oppurtunity to design a DPM for a firm, I put the 555 clock in place CD4009 clock shown in intersil, to derive the -5.

Potentiometer Dial GIF for above circuit to be used to make a hand-held avo-meter is here.

Analog Dial AVO Amps-Volts-Ohms meter

Small Electronic Testing Tools - Analog Dial AVO Amps-Volts-Ohms meter

Test Measurement and Test jigs

Test Tools are needed for Troubleshooting and Repairing Electronic Gadgets, Equipment, Electrical Panels and Machines. Precision Instruments are required for calibration of field and machine control electronics. These are also required by the R&D engineer for design and development of new products and trying out new concepts.

Test and Measurement

Test Measurement and Test jigs - delabs

In Production testing, Production Engineering, Quality Assurance QA-QC etc. You need to build Test Jigs, Configure Automated Testing depending on the size of project or budget allocated; yet it has to be made flexible, scalable and modular. These require instruments or blocks that can be adapted and reconfigured or even interface with a computing network for automated testing, reporting and analysis.

Special Electronics come with every tool or gadget these days, A Slide calipers has a LCD display, Digital Readouts on mechanical instruments can help measure even sub-microns easily. Analytical and Chemical Instrumentation is another specialized niche. Then we have medical instrumentation which is more demanding in quality and requires sensors that are small, very sensitive and safe.
Instrumentation goes into all these and beyond. The day we find water on mars, It is only because of a precision instrument at the helm of things.

These are basic measuring circuits you can build for your home lab. I have documented a lab DMM i had built for my use many years ago. the circuits may have errors, build it only if you understand.

Thursday, February 23, 2012

Custom Built Test Instruments

I designed and built many custom "engineered" Test Instruments. They were not prefect, as only one or two were fabricated. That means it will be costly to produce such instruments. It is just like tooling, you have to make some numbers to recover costs, or price it very high to compensate for the wastages and iterations. But things are better off now for building custom instruments. Yet a design firm has to make modules and keep ready, then put together a solution/system, program and ship.

Custom Built Test Instruments

When making custom equipment, you have to have an extended service agreement like 5 years. Also request a minimum order of at least 5. Make your R&D and Inventory Modular. That way it is profitable and some money available for reinvestment on instruments and Equipment for calibration and quality.

Transistor Beta and Vce Tester

This was a Beta Hfe and Vce Measuring Instrument used in Incoming Inspection of Power Transistors made by me 20 years back.

Transistor Beta and Vce Tester

It is a Test and Measurement Instrument to Evaluate the Beta of a Semiconductor Transistor at different Ic and Vce. This was an early custom test instrument.

Wednesday, May 19, 2010

Test Measurement Instruments by delabs

These are Instruments that Jack built. Here read Jack as me, delabs. Some were hand made, some in the form of workflow of a small firm with professional equipment. Some made in quantities, other a couple or more for R&D.

Test & Measurement Instruments

Test Measurement Instruments by delabs

Test and Measurement is all about Measurement or Metrics. Without this, every other part of electronics becomes like boneless entities.

Relationship between Instrumentation and Automation - In Test and Measurement and Industrial Process Control a common factor is instrumentation. The measuring aspect is common to both. T&M instruments are used in Testing, Research,Automated Testing, Troubleshooting and Servicing.

Instruments i designed and built. (long ago).
Process control Instruments are used in Production Lines made of Machines in a Factory. It could be Counters and Timers used for Textile or Steel Industry. It can also be Temperature and Pressure Controllers used in Oil Refining or Food Processing.

So you see a difference. We have handheld Test Instruments like DMM and Scope and We have Handheld Instruments for Gas Monitoring or Humidity too. In automated testings we have rack mount test instruments. In Control panels we have Rail Mount carrying DIN standard Instruments.