Elegant, miniature, powerful – Marquardt 1858 double switch

If you´re searching for a rocker switch with small dimensions and a great design, then you shouldn´t overlook the Marquardt 1858. 

Marquardt 1858 is a miniature 2-pole switch with 10A/250VAC rating, made of immediately self-extinguishing material (UL-94V0). Inspite of small dimensions it handles up to 100A inrush (capacitive) currents. Silver plated terminals provide a low resistance and a safe plugging of connectors (fastons) is ensured by double fixing of terminals in the switch housing. Ambient temperature on the terminals side can be up to 100°C, what enables to use the switch even in pent conditions of power applications. For an increased dust and water protection you can use the 203.089.011 transparent cover. The switch surface is silky matt with an abrasion-proof marking.

Small dimensions and an elegant design make the Marquardt 1858 switch suitable for applications like for example a main power switch of various devices, as well as for a control of peripherials. In the 1858 series there are available switches in various versions, in stock we keep 1858.1103 type. Detailed information will provide you the Marquardt 1858 datasheet as well as Marquardt switches overview.

Elegant, miniature, powerful – Marquardt 1858 double switch – [Link]

DBCalc – dB Calculator freeware

Neat small unit converter for electronic engineers. If you found this useful, but lack of features, please be free and report/ask for updates. This tool is completely free.

DBCalc – dB Calculator freeware – [Link]

EqResistors 2.0 – Resistors Combination Calculator

 

Using this tool you can find closest simple resistors net of standard resistors values. Select net, select required resistance and you will got pair (or triplet) of resistors with combined value closest to your needs.

EqResistors 2.0 – Resistors Combination Calculator – [Link]

PF 2012: Soselectronic.com Christmas video greeting for you

 

In everything we do we try to be different. Our Christmas greeting is this year more personal, faster, more mobile, louder and environmentally friendly …

When we reflect on this year’s greeting, we wanted to do it otherwise. What is typical for us, so we try to diversify it from other distributors? Certainly it is also our personal relationship with you. Into everything we do, we try to put a personal approach. Indeed, it is not just about the components, but also about people.

Therefore, we also wanted with this Christmas greetings to get closer to you. Although it is not in our power to visit each of you personally before Christmas, we use available technology to be at least close to it.

And he’s still a positive. Our greeting is environmentally friendly, because we save a few trees produce CO2 eliminated in connection with distribution of paper greeting …

And here is our Christmas video greetings for you … we are an international company so our greeting is also in the foreign languages :).

PF 2012: Our Christmas video greeting for you – [Link]

DIN rail enclosures CEM22 with complete accessories

For an easier orientation in the CEM22 enclosures product line, we bring you an overview of suitable connectors and sockets for particular enclosures.

We introduced CEM22 DIN rail enclosures series to you in the separate article. As you can best exploit dimensions of enclosures when using appropriate connectors and sockets, we bring you this overview of suitable connectors. By their usage you gain a surety of mechanical compatibility and a professional appearance of a whole set. All below-listed types are already standard stock goods.

DIN rail enclosures CEM22 with complete accessories – [Link]

Determining LED Rated Life: A Tricky Challenge

Steven Keeping writes:

As high brightness LEDs become practical alternatives to incandescent and fluorescent light sources, manufacturers are under pressure from a skeptical public to publish realistic operational lifetime figures.

Accurate lifetime estimates for LEDs operating in specified conditions would help designers select the best device for their product, manufacturers set warranty periods, and consumers compare cost-of-life of LEDs with conventional light sources (an important justification given LEDs’ higher initial purchase price).

Consumers understand that an incandescent bulb may last 1000 hours and a compact fluorescent light (CFL) perhaps five times that before catastrophic failure, but are less familiar with solid state lighting sources.

The problem for the manufacturers is that properly driven and thermally managed LEDs can last for years, so sitting around and waiting for an LED to fail is not a practical test regime. Secondly, an LED can either fail catastrophically or, more likely, suffer from a slowly diminishing output. At what point should such a fading LED be considered as ‘failed’?

This article discusses the standardized test method for determining approximately how long a high brightness LED will remain “fit for use.

Squeezing Energy from Photovoltaic Panels

Jon Gabay writes:

Renewable energy can be an expensive endeavor and photovoltaic systems are no exception. Ground and roof-mount frames have to be tough enough to handle weather extremes and conditions, and can be very costly even without tracking.

If you use storage batteries, there are large initial expense and the replacement costs every so many years to be considered. On the positive side, 90 percent of the materials in a lead acid battery are completely recyclable. Chargers and inverters are not cheap either.

The panels are the biggest expense. Fortunately, with higher manufacturing capacities coming on line, photovoltaic panel pricing is starting to come down, but not yet to the level of mass deployment.

In 2008, the price of $1000/kg of silicon kept panels at process of three to four dollars per watt. Combining the increase in silicon production capacity with the global slowdown has dropped the price to the $40/kg level meaning we may soon really be at the coveted one dollar per watt price point that many say will make photovoltaic solar on a level playing field with non-renewable energy technologies. We are presently around $1.50 per watt.

To get to that level of high deployment, payback has to be quicker. The lower cost promise of solar panels is one factor for quicker return on investment. The other is the changed architecture of photovoltaic systems stemming from the use of micro inverters.

Either way, the market for the electronics that make use of the solar energy more efficiently is about to explode.

Squeezing Energy from Photovoltaic Panels – [Link]

Altera UP2 Projects – EECE 343 Fall '11

pyroelectro.com writes:

One of the professors (Jowel Yusta) at CSU Chico University’s Electrical Engineering department was kind enough to pass on some small Altera UP2 FPGA oriented projects that his students built for their yearly EECE 343 – Computer Interface Circuits course.

The EECE 343 course focuses on the different ways that digital electronics pass information to each other, for example USB or PS/2. The Altera UP2 board might be quite antiquated compared to the newer university boards that are available (especially compared to the DE0-Nano) but it’s still a straight forward and simple platform to work with. Such things are extremely rare in electronics and are great for learners.

Altera UP2 Projects – EECE 343 Fall ’11 – [Link]

Altera UP2 Projects – EECE 343 Fall ’11

pyroelectro.com writes:

One of the professors (Jowel Yusta) at CSU Chico University’s Electrical Engineering department was kind enough to pass on some small Altera UP2 FPGA oriented projects that his students built for their yearly EECE 343 – Computer Interface Circuits course.

The EECE 343 course focuses on the different ways that digital electronics pass information to each other, for example USB or PS/2. The Altera UP2 board might be quite antiquated compared to the newer university boards that are available (especially compared to the DE0-Nano) but it’s still a straight forward and simple platform to work with. Such things are extremely rare in electronics and are great for learners.

Altera UP2 Projects – EECE 343 Fall ’11 – [Link]

Measure temperature and humidity using DHT11 sensor and PIC

embedded-lab.com writes:

Measurement and control of temperature and relative humidity finds applications in numerous areas. These days devices are available which have both temperature and humidity sensors with signal conditioning, ADC, calibration and communication interface all built inside them. The use of such smart sensors greatly simplify the design and reduces the overall cost. We discussed in past about Humidity and temperature measurements with Sensirion’s SHT1x/SHT7x sensors. These sensors are capable of measuring both temperature and relative humidity and provide fully calibrated digital outputs. While  SHT1x/SHT7x are very accurate sensors, they are still expensive for hobbyists use. This articles discusses the DHT11 sensor which also provides calibrated digital outputs for temperature and humidity but is relatively lot cheaper than the Sensirion sensors. The DHT11 sensor uses a proprietary 1-wire protocol which we will be exploring here and implementing with the PIC16F628A microcontroller that will receive the temperature and humidity values from the sensor and display them on a 16×2 character LCD.

Measure temperature and humidity using DHT11 sensor and PIC – [Link]