Missing Flight MH370 – some brief lessons in hindsight

MH370 – the conspiracy theory sells newspapers!

 

I am not a big fan of the news media when it comes to conspiracy theories and sensationalism. With the missing Malaysian MH370 in everyone’s mind the first thing that became most apparent was our sifting through media reports rather than wreckage. The first theory was the Boeing 777 itself, wing’s breaking off caused by tiny cracks in the manufacture process. Maybe we should first take a step back and have a look first. The Boeing 777, like the 747 and 737 has been around for many years, has an incredible safety record and if there was any inkling that there was a fatal flaw in the wing structure Malaysian Airlines would have surely grounded their fleet.

MH370 - avionics
Cessna Citation Avionics – Radar system Wiki credit Dtom

An incident which caused damage to the wing-tip at Shanghai airport was the next theory. The plane did have maintenance ‘A’ carried out in February, which consists of possibly an in hanger inspection at the airport. The 777 is less than 10 years old, relatively new for an aircraft with such an impeccable record.


 

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The MH370 flew to beyond it’s ceiling. True, according to radar pings the flight did indeed ascend to beyond 40 000 feet but this was within the capability of this aircraft. In fact according to data the aircraft climbed to beyond 45 000 feet and then dropped to 20 000 feet. According to feedback from specialised sources the radar is not known to be all that accurate at very long ranges. Commercial aircraft use a transponder service which relays important information back to the radar receiver, military radar would only ping getting altitude and range, computing the necessary information to get speed and heading.

Flight MH370 – No communication, no leads and no evidence

What is very much apparent is that the authorities do not have the necessary information to formulate a qualified and therefore rational answer to the whereabouts of this aircraft. At present the world gets information from satellite imagery and the Australian military have been very transparent. Search and rescue exercises no matter where it is executed is an extremely expensive process and with modern technology the media will always be there. Again, why all the hype to sell a story when we have families back home hoping against all odds that their loved ones are safe.

Some facts: People leading an investigation into a missing aircraft or ship are highly trained individuals with many years experience. They normally have a team to assist them – MH370 went missing without trace and we have absolutely no clue as to what happened. Not knowing something will always be well and firmly attached to a theory.

 

Flight SAA295 – The Helderberg

Remember ill-fated flight 295, the Helderberg, which crashed into the Indian Ocean near Mauritius? South Africa was not a popular country in those years and the demise of the Helderberg which belonged to SAA, a government owned business, carried more theories than a possible alien bomb attack on New York. What we do know is there was a fire on board and well-known forensic scientist David Klatzow believed this to have been possibly started by rocket fuel, an un-listed cargo on this flight. I wonder if everything was manifested on flight MH370? How unstable is Lithium Ion really?

Flight 447 – Air France

Air France’s Flight 447 investigation also carried tremendous interest, the first always being terrorist action and bombing. If you are an avid watcher of Aircrash Confidential, the bombing theory is the most abundant and once the forensic team have completed their investigation it nearly always comes down to pilot or air-traffic control error or mechanic ineptitude. The aircraft is an extremely robust machine but will always be at the mercy of the human element.

No news is sometimes good news

While the authorities take the necessary steps to trace this missing aircraft we need to look at some remedial action. First of all sometimes no news is good news. We all shout for transparency but in the wake of this incident I wonder just how much damage is being done by the media. There seems to be no discipline neither a code of conduct. It is right that the public should know – but the truth. Publish facts. The internet, whilst being a wonderful propaganda tool, is also a dangerous tool for the uneducated.

Emergency Location tools

Flight MH370 is not unlike any other flight except at this stage we do believe that the aircraft lost all forms of contact with ATC and to date there has been no reception of any form of emergency locator transmissions (ELT). Although the ELT is found on most international run airliners the decision to fit is controlled by the airliner’s aviation authority and not an international body. Surely this should be amended. Also Air France flight 447 was a nightmare to recover because of the limited time span the ELT can radiate the aircraft location (batteries), depth (in the sea) and of course, neighbouring shielding or interference. Surely the ELT or EPIRB (emergency position-indicating radio beacon) should have a backup of sorts. Searching through mandates on ELTs and their installation it comes as no surprise that the ELT is prone to erroneously trigger, these false alarms necessitating loss of man hours and productivity. Perhaps we need to re-look at this life-saving device, construction, where it is housed and prevention of false triggering.

 


 

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HF Radio Links

We read often about an aircraft losing contact because of the line of sight transmission systems used but yet an aircraft also has a HF transmitter, hopefully! In certain parts of Africa an approach is made where the pilot may need to use HF linking because there is no VHF available. VHF has two pitfalls, one being range and the other, direction. HF is not nearly as clear but somewhere, somehow HF radio links will always be made. This may sound vague but in essence the higher the frequency, the less power is required for a given range and secondly, depending on the ionospheric conditions there will always be an ionospheric skip favouring certain frequencies due to shifting layers of the ionosphere, generally known as the KennellyHeaviside layers. Simply put, during the night we would use a lower frequency and during the day a higher frequency. This is a very simple explanation but forms the basis of most HF comm.

The problem with HF communication are the aerials – the lower the frequency the longer it needs to be or at least effectively. Using satellite and VHF as a primary means of communicating has proven to be effective but as long as there is no incident. Using UHF (ELT or EPIRB) has also proven to be effective but has a limited range (VHF communication) or limited broadcast time (ELT). HF has proven to the most reliable and effective means of transmission over the last 100 years. The problem is that we have no control over satellites, neither whether the aircraft will be in range of a VHF link. You will always have an HF link whether it is 4MHz or 16MHz. Design engineers should start looking at the way in which we communicate in an emergency.

An Overhaul is needed

As we become more technologically focused we are losing sight of functionality, what works under any condition – satellite communication is quick to set up and mostly reliable. In very bad weather?

Black boxes have not really been overhauled over the last few years and certainly have not kept up with technology,  Radar, at least the secondary type radar used to obtain information through a transponder only when the transponding aircraft is willing or able is also really not negotiable. MH370 could switch theirs off.

There is a million and one theories out there and also a million and one solutions to the problems we face right now. The aviation authorities should be looking at overhauling the next generation of safety and locational devices on aircraft, not least the way in which we communicate. A fire on board a ship is a dreadful thing to happen, possibly one of the worst. Put yourself in a position where you are36 000 feet above the sea and there is a fire onboard. I’d rather be on a ship any day – time will be on your side in most cases. Not on an aircraft.

What is indeed the saddest part about missing flight MH370 is how poorly the news broadcasts have been propagated, based on very little information and how we put on the table the most abundant piece of knowledge we all have: Hindsight.

 


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Science on the Web – Part Three, All About Circuits

All About Circuits – Tony R. Kuphaldt

 

Tony R. Kuphaldt is an instructor at Bellingham Technical College in Bellingham, Washington.
If you are planning on a career in electrical or electronic work All About Circuits is dedicated to you. Go through each and every chapter (under sitemap), do not skip and do the tests. Electrical or electronic students have one thing in common, they love reading and they love reading about how things work.

Technically minded people are not usually money-savvy because money is of secondary importance. Technicians never die of starvation – Confucious 551BC ~ 479BC


Not that long ago a student at any learning center had to go to the local library to find literature on his subjects of choice or purchase the books which are stipulated in the syllabus. Things only got better with the internet and much better with Wikipedia. Yes, academics strongly advise their students not to plagiarise neither get their information from Wiki based on the inaccuracies posted but for all intents and purposes Wiki serves a really great purpose and by knowing the fundamentals and doing further research a student would be able to sift the fact from fiction. Here’s the thing though, sometimes we are just lucky enough to find a gem of a website where the scribe is indeed an academic and indeed posts their own training to students or lecture material for free on the web.


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All About Circuits is just such a website.  I can guarantee any avid reader of literature where core material is based on electricity and magnetism, audio or circuits in general, web linking will take you to Rod Elliott, Tomi Engdahl and/or Tony Kuphaldt’s All About Circuits website.  I first came across this website quite a few years back whilst writing a program to determine the correct Power Factor Correction capacitors for an inductive load on an a.c. circuit. I studied a.c. circuits in the mid to late 70s and really never needed to use any circuit design remotely associated to power factor correction until then. Because of the sudden interest in seeing what else Mr. Kuphaldt’s website had to say I spent the better part of five hours going through the website, so brilliant it was. Yes it is open commons but who cares. It has been authored extremely well and caters for the needs of most electrical or electronic students.

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What makes All About Circuits so wonderful to browse through or if you are a student, starting a brainstorming session, is the Q&A, forums and the lack of all the bells and whistles inherent to any website selling you a product. Here the product is ‘read, learn and experiment’ and it is free after all.
Previous: Science on the Web – Australia and Rod Elliott – Science on the Web – Tomi Engdahl

 

 

SSB Transceivers down the years

SSB Transceivers - the distress silent period.

SSB Transceivers – In the very beginning

Bouncing back from our article on the ARRL we thought it may be pertinent to drop in a few words about SSB communications based on two emails we received from interested readers, both of whom are keen listeners on the amateur bands.

SSB Transceivers - the distress silent period.
Marine Radio Office clock – Wiki credit: LuckyLouie

Although this may be a bit off topic for our web-site it still plays a rather important role in interested parties in getting spares for old amateur equipment, possibly even marine or aviation.

[for interest’s sake, for those interested to know the colour markings on the clock above show the old timer’s :mrgreen: distress silence periods – 2182kHz (telephony) in green and the 500kHz (morse code) in red. Although this may not appear to have had anything to do with this article it sure played a vital role in saving lives].

SSB Transceivers – Double Sideband and Tuning for a Dip

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A rather lesser known fact is that although the means to transmit and receive SSB modulated signals has been around for nearly a hundred years I still came across many fishing boats in the late 1980s still using double sideband and rather strangely, most of the operators were not familiar with the proper tuning of these devices. Many of the operators would tune for maximum cathode current in the power amplifier or believe it or not, the red line. There was one specific fleet which all had the same radios and not one of them had a ‘working’ aerial current meter only to be discovered later that they were in fact tuning for the ‘red line’ in the cathode current and therefore it would not show antenna current. Yes, the red line was the danger line and certainly was not optimal radiation output. (for those not knowledgeable about RF output stages, one would tune for a dip in cathode current (or anode current) as this sudden dip would relate to resonance in the antenna circuit).

SSB Transceivers – Antenna and transmitter auto-tuners

I found many of the auto-tuners in their hey-day wonderfully complicated but they either did not work for long or most of them just did not work at all. The sea air may be good for the old sea-dog’s chest but played havoc on any transmission line. The best transmitters were almost always manual devices. I talk not of modern day devices – the response is almost immediate and of course, lots of protection.

Valves were also more robust than their semiconductor brothers – I very seldom came across valves that suddenly just decided to fail. Try that with a mismatched tank circuit on a bipolar transistorised RF transmitter – breakdown was almost always immediate so the manufacturers had to build in a lot of safety circuitry to protect these devices. Often they too failed. So, no – in the good old days valves ruled the roost and even until the late 1900s were more common in the high powered HF transmitters of the day. From a costing point of view they ‘may’ have been cheaper as well although I do recall some of the blast air cooled devices would cost in the vicinity of about 250 dollars a pop. There were two of them in parallel as well.

From a technical viewpoint I was not fond of the older auto-tuning transmitters. Although they were predominantly used on HF telephony equipment I just did not find them reliable enough for an inexperienced person having to use the apparatus in an emergency.

SSB Transceivers – the power supply

SSB transmitters are operated in linear mode or class A or AB. This in turn means a very hefty power supply and of course, the power amplifier requires very high powered output devices, usually blast air cooled. Transmitters are designed to change bias as the operator changes modes, from CW to SSB. In my experience, a very common problem where the operator receives a ‘bad tone’ signal from another operator the power supply would have been the cause, either as an audio ripple modulation or in the excitation process the entire frequency synthesiser becomes unstable. Modern techniques prevent any unwanted radiation, something the earlier operators did not have the luxury of. With any circuit which utilises a frequency generating component for radiation the power supply has to be well designed and not only that, designed to handle either mismatching through incompetence or catastrophic failure of the antenna system. Again, modern techniques will prevent any form of radiation under those conditions. Not so with earlier equipment – the operator was trained to prevent this from ever happening. It was not uncommon to hear flashovers in the earlier valve operated gear.

SSB Transceivers – SSB Equipment

SSB Transceivers - the ring bridge modulator
Ring Modulator – the heart of the suppressed carrier system – credit Wiki

As a lecturer once explained, ‘why use a block of wood to penetrate a piece of foam when you could use a needle’. Quite right. This sort of summed up the SSB transmitter. The heart and soul of the SSB transmitter is the modulator, most commonly the ring-bridge mixer. See Image two. The filter in a marine band transitter would be used to remove the lower sideband. Amateur hams filter out the USB or LSB depending on the band used. Modern transmitters do this automatically otherwise it could be manually done like on your CB radio. At the receiver, the missing carrier is re-inserted. However there are other factors to take into consideration.

AGC or Automatic Gain Control

The AM radio receiver uses a circuit called AGC to reduce a phenomena called fading. As the signal at the receiving antenna becomes weaker the AGC control opens the gain of the IF (intermediate frequency stages) which in turn increases the audio output of the receiver. This AGC control is designed to be slow acting which is one of the reasons why sometimes the broadcasts do sound louder and softer. More elaborate AM radios, especially ones in which are used for telecommunications have an AGC control which can be adjusted by the user. Going one step further, SSB transmissions without carrier (suppressed carrier) require a fast acting AGC control – the signal when modulated comes through to the receiver in bursts so the AGC needs to detect this signal very quickly and then allow a controlled decay on the gain of the IF amplifiers.

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After the Second World war

Interestingly enough amateur radio played a major role in promoting SSB after WW2. It’s not surprising – SSB after all is vastly superior to double sideband full carrier especially when the amateur is licenced only to operate at a restircted power output, unlike the MW goliaths of the commercial radio stations. Anyone old enough remember Radio Moscow, the only city in the world that could reach all four corners of the globe, swamping out any nearby transmissions as well.

Single Sideband Suppressed carrier transmissions also have another huge advantage – no hetrodying interference (whistling or audible tones) of the received signal. This plays a major role in selecting your optimal frequency for communication as well as the ionospheric conditions of the day and night.

Disadvantages

We can cover all the advantages of SSB transmissions but are there really any disadvantages? Possibly because the receiver has to be able to re-inject the carrier but all communications receivers have this ability. Any adverse atmospheric conditions would affect your communication distances as a whole, it is not just an SSB thing so to put it mildly, SSB really has no disadvantages. It is used in land-line telephony equipment and television broadcasts as well, to name just two.

Where to from here….

I have covered the very basics of this form of transmission here for our newcomers – however for the old bandits and salts it would be great if we could get some of your pictures and add it to the museum.  Just like any old machinery, you may be dead but you ain’t forgotten.

The radio amateur is making huge inroads in digital broadcasts using SSB technology and this will be covered in our next article. Although our circuits nowadays are fully transistorised (for use of an older word), becoming smaller and smaller and digital is overtaking analogue SSB Transceivers still have two things in common with their older brethren, the high powered units still have mammoth power supplies and use the same principles.

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The ARRL – The American Radio Relay League’s first 100 Years

The ARRL turns 100

“To promote and advance the art, science and enjoyment of Amateur Radio.”

 

As an add on to our last article by Darren Wolff on Wireless Technology we thought it may be pertinent to add in some interesting titbits about the ARRL.

I am sure that many of our readers are in fact amateur hams and a million kudos to you. Although I was a ‘Sparky’ many years back I never did the amateur ham exam and thoughts are on possibly doing just this in the next year. Although I have been told that one forgets morse code over the years I really doubt this very much – it more or less gets hardwired into your brain, just like any language. We may get rusty, but never forget. Practice makes perfect.

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To get to the very beginning:  In 1914 the American Radio Relay League was founded by Hiram Percy Maxim. This is an interesting date because the ARRL celebrates it’s centenary this coming May.

Amateur Radio and the Rise of SSB is an excellent read by McElroy. Don’t forget to read about the ARRL on Wiki as well.

For many youngsters the ARRL was and still is a stepping stone into the telecomm industry and even more so, electronics in general. SSB and satellite communication play a vital role in our every day lives, something which we are either immune to realising or have forgotten about. The ARRL have saved lives countless times in a crises and will continue doing so.

Over the last 20 years the amateur ham has had more exposure to the full potential of their home based computer systems using only a sound card, a receiver (or transceiver once qualified) and I/O devices.

To get more information locally do a search under Google to find your local offices and when to register for the exams.

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Watch this space

 

 

Wireless Technology – the world of AM, FM and Wi-Fi

Wireless Technology - marine emergency radio

Wireless Technology – Back to our Roots

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Although many of us see Wi-Fi as the be all and end-all of wire free communication we could not be further from the truth. This article does encompass trends over the last hundred years which has seen a trend to move to UHF bands and use very sophisticated forms of modulation, the rule is always ‘the simpler the better’. Yes, I was in the telecom business many years back and yes, this article may lean towards older techniques and yes, we aren’t living in the dark ages but sometimes we lose sight of the skills that our forefathers (and mothers) had. Modern trends are extremely reliable but when they do fail we are miserable, from your local power grid to an internet connection.

Wireless Technology - marine emergency radio
Survival Radio BC-778 source Wiki/Credit Arnold Reinhold

Over the last two hundred years there has been, in my book, four great strides to bring us modern radio telecommunications:

  • Firstly, the discovery of electromagnetic waves – Maxwell, Hertz and Hughes.
  • Secondly, the discovery of the vacuum tube principle, thereafter it’s implementation in amplitude modulated circuits.
  • Thirdly, the design and implementation of FM or Frequency Modulation.
  • Fourthly, the strides taken to reduce bandwidth with increased power to deliver a rock solid signal, the implementation of SSB. (Single Side Band).

One thing that stands out, head and shoulders above the achievements of commercial enterprises such as Bell Labs whom have been credited with almost anything related to telecommunications is the perseverance and incredible work done by the ARRL (American Radio Relay League).

Although most youngsters would never have heard of SSB, like the challenges facing RCA to develop a broadcast picture in colour on the same frequency and bandwidth of a monochrome signal, SSB was indeed an incredible leap forward – nearly 100 years ago.

Adendorff – ToolMart – Machinery Mart

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admin 2013-12-27 10:06:19
admin

Company/Business Adendorff – ToolMart – Machinery Mart
Website http://www.tooltime.co.za/
Business Type Reseller
Category/Genre Machinery – Tools
Posted By
admin

Core Business Reseller of Tools, Generators, Pumps etc
Address 1 cnr 152 Rosettenville Road
Address 2 Turf Side
Suburb Springfield
Town/City Johannesburg
Region Gauteng
Country South Africa
Zip/Postal Code 2190
Telephone (011) 434 7000
Details/Additional About us
Our Vision

Adendorff Machinery Mart sources equipment from all over the world to offer the greatest range of products at the best prices.

The changing global economy is placing new and increasing demands on companies, and the market place is marked by increased competition worldwide.
Within this fast paced global economy, change is the norm. Environmental, social and technological change with the increased internationalization of business can only mean that long term planning is risky but absolutely essential.
Great quality products and supplying excellent service to customers is imperative. It is also essential to ensure that processes are in place for exceptional interaction throughout the business and creating a strong staffing group that would secure a company that competes with world markets.

In creating a strong staffing group Adendorff Machinery Mart believes in the development and implementation of Organizational Development & Training that is recognized for its ability to understand, conceptualize and deliver total solutions and to provide consistent, professional and long – term relationships with its customers and will assist in developing well rounded staff in all aspects of business

This is what Adendorff Machinery Mart’s vision is all about, and we pride ourselves in focusing on a long term commitment to our vision. Based on our strong commitment to our vision we believe that we place ourselves in a position whereby our decisions, abilities and actions will prove us to be a great market leader within our field.

Air Conditioners – simple and cheap

Air Conditioners – Keeping the costs down

Like most things, the innovative have discovered how to keep themselves cool at a fraction of the cost of an installed split air-conditioner which uses a compressor and refrigerant. Be warned though, depending where you purchase your hardware it can rack up more than a hundred dollars like it did me.

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The Instructables

Here is a link to a cooler which uses cold water to cool down your environment. Although it professes to be a spot cooler I did make one and with leaks and all it cooled the temperature down by at least 5 degrees C (31C to 26C) in our living room. Admittedly I use a larger fan, diameter 40cm (16″), more piping around the outer area, piping is 8mm diameter (5/16) and I used glands to seal off the ice box. I could not get the plastic pipe to seat properly against the copper pipe which created one leak which subsequently was fixed by rolling two turns of insulation tape around the circumference of the copper to  make a tighter fit for the plastic pipe.

Although one can pick up a 2nd hand A/C unit with warranty for about 200 dollars the biggest problem here is the running costs – electricity isn’t cheap and I would need an 8 000 BTU to 10 000 BTU air conditioner for our living room Mild climates don’t always call for drastic means but anything above 30 degrees C does mean a bit of discomfort. Unfortunately I would have loved to have tested this ‘alternative’ means to cooling down the air in our recent 40 degree C bout of weather but like all mother of creations, we do the deed after the fact.

Was it worth it? I think using the same principle with a proper evaporator would have being much more efficient. This will be my next project. Secondly, whether running copper piping into the ice box would make much difference is debatable – I left that out. Further experimentation on this unit in future – it’s an easy build and fun too. Insulating the plastic piping is very important. Power consumption – water pump is a ViaAqua VA-470A 1800 L/Hr or 800 L/Hr at 1.4m 60W and the fan is driven by a 70W motor. Locally we pay about 16c kW/Hr so we are looking at about 2c per hour or over a month continuous, 15 US Dollars. Of course the freezer had to make ice so this would have cost a few dollars more all in all, a much cheaper alternative to a 3kW air conditioner. As efficient, no.

A Water Evaporator System

I liked this post on the Instructables – maybe a bit more sophisticated than the average project which means more time and money but a solid design and one which will work well. Go here.

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and of course, last but not least, using a home made evaporator come water cooler:  http://www.instructables.com/id/Free-Air-Conditioning/?ALLSTEPS

 

Understanding your Refrigeration System

Refrigerator

Your refrigeration system – the heat transfer principle

Refrigeration is one of the most widely misunderstood topics amongst the DIYer community yet we have a slew of articles and explanations covering this subject. So what makes it so difficult to understand?

 

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Many articles written by specialists rely on the reader’s own understanding of the fundamentals and the refrigeration cycle, even its most rudimentary form can go over one’s head if by design we leave out the basics. As an example, explaining power dissipation in a circuit would be near impossible if the reader did not have a firm grasp of Ohm’s Law.

Refrigeration System - Einstein and Szilard
Einstein/Szilard Refrigerator (Illustration/annotations by P. Brandon Malloy)

In refrigeration we need to understand that first and foremost by compressing a gas there will be heat generated. Compressing a bicycle tyre pump into your hand is a really great example. By releasing this pressure suddenly the gas cools down.

Fluids used in a refrigeration plant, called the refrigerant, boils at a much lower temperature than water at the same pressure. E.g. water boils at 100 degrees C (212F), the refrigerant may boil at 4 to 10 degrees C (40F~50F).

A refrigeration system works on the heat transfer principle – cold to warm, warm to cold. Evaporated (fluid to gas) and condensed (gas to fluid). Taking warm air from inside and dumping it outside. Simple and reliable. But just what makes it tick?

The refrigeration system has five basic parts:

  1. The compressor,
  2. the condenser (outside),
  3. the metering device, an expansion valve,
  4. the evaporator (inside),
  5. the thermostat.

The first four all form part of a closed loop. The thermostat is a temperature controlled switch.

The heart of the refrigeration system: The compressor

 

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At the heart of the system is the compressor which forces the refrigerant into the condenser coils which are usually outside the building – the higher pressure (called the high side) causes the refrigerant temperature to rise to between 40 and 50 degrees C (120F~140F) before reaching the condenser. As the refrigerant passes through the condenser coils a fan passes the cooler outside air over these same coils – heat transfer takes place, cooling the refrigerant causing the refrigerant to condense and become cooler. The compressed warm refrigerant then passes through the expansion valve releasing pressure to become colder still before passing through the (low side) evaporator coils which then absorbs heat, cooling down the area in which the evaporator unit is placed before being sucked back into the compressor to process the next cycle. This closed loop system therefore collects heat inside and dissipates this heat outside. Both air-conditioners and domestic refrigerators use the same principle.

Refrigerants

Refrigerants are used based on their boiling temperatures. They cannot be mixed. Different applications use different refrigerant. Certain refrigerants, such as Freon R-22 is gradually been phased out and in some countries illegal to sell (or buy). R-410A is now one of the replacement types for R-22. To purchase refrigerant you will need to be a licenced refrigerant engineer, installer or technician.

The BTU in your refrigeration system

The BTU or British Thermal Unit is the amount of energy needed to raise or lower the temperature of one pound of water by one degree Fahrenheit at one Atmospheric pressure and is equal to about 1055 Joules of energy. The BTU is used in metric countries as well. As a unit of power 1000BTU/Hr is equal to 273.071W.  12 000BTU/Hr is therefore equal to about 3.5kW. Now you know why air conditioners are expensive to run.

Easy Maintenance to your air conditioner or refrigerator

One of the most common causes of failure to your refrigeration system is by NOT cleaning the evaporator or condenser coils at least once per year (radiator fins). This causes the compressor to work harder than it should. Another cause of premature failure of an a/c system is running the air conditioner at settings which would be impossible to achieve or leaving the doors or windows open in a conventional system (not water evaporators, which work best when well ventilated for humidity reasons). On a hot day it is not uncommon to find users setting the air-conditioner to the lowest possible setting – sometimes to as low as 16 degrees C (60F). An under spec’d air-con is another cause for premature failure – often even the installers get it wrong.

Do not transport your domestic refrigerator on it’s side unless you plan to leave it for at least 24 hours before plugging in and switching on.There are numerous reasons for this, one being to allow the refrigerant to settle.

Modern trends

Modern refrigeration techniques have mainly involved changes to the refrigerant and producing higher efficiency systems to cut down on running costs. Although the principles remain the same, inverter driven compressors have become more common today as technology has improved, the modern variable speed compressor no longer goes through a stop/start process which although costing more, lowers operating costs. The refrigeration system therefore still relies on tried and trusted techniques rather than a complete metamorphosis.

Go to Simple and Cheap solutions for Air-Conditioners

 

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Combatting the Energy Crises

Energy Crises - the ultimate cost saver?

The Energy Crises – Home Users

Let’s face it, love it or hate it everyone these days is harping on about what they are doing to reduce energy wastage. A small house with two occupants can consume between 300 and 600kW over a period of a month. (300~600 units). The biggest pest is the water heater or geyser. By switching the geyser off and on daily some home owners are adamant that their savings are between 10% to 50% per month. This is totally dependent on how many users we have and the times that the geyser is cycled. What is important though is that the utility companies really want your geysers off during peak usage periods. Modern geysers may be controlled by the utility company to prevent current draw during peak periods.

Energy Crises - the ultimate cost saver?
Solar boiler on a rooftop in Israel. Source Gilabrand

There is scientific evidence proving that cycling the geyser on and off saves money but a 50% saving is doubtful unless it is off for a lengthy period of time running into a few days per month. The main issue here is that the temperature drops significantly below the thermostat cut-in region and more power is then needed to bring the temperature up to cut-off. Installing the geyser in a high ambient temperature region of the house will make a difference, along with a blanket and thermally isolating the piping. Being a non-scientist I think the way in which we heat the water in a geyser is archaic and needs attention.

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Energy Crises – knowing your power factor

One of the biggest scams to hit the open market is applying ‘power savers’ to your home or apartment mains supply. There are units sold by the thousands which in reality has… nothing inside it which will save you any money whatsoever, in fact you will be blowing money unnecessarily. Not to harp on a well worn subject but rather on a very well written topic you can veer off to Rod Elliott’s website and find out more on power factor, which is really a very scientific subject and does have engineering students pulling their hair out – go to Power Saver Fraud to discover what really ticks and why not to sink your hard earned cash into any of the myriads of well-marketed but totally worthless pieces of snake-oil gadgets available to the public. The unsuspecting public will think twice or even three times about installing a 15 dollar device which will save you 50% of fuel costs but not enough thought into paying 100 dollars for a device ‘reputed’ to save you electricity costs.

Energy Crises – what else for home users

Here’s food for thought. Ever notice how one skimps on their bad driving habits when their fuel drops to within the reserve space of the fuel tank? If you are fortunate enough you may have an electricity meter in your house which works on a pay as you go.The unfortunate part is that the meter showing consumption is usually mounted too high or in a cupboard, inconvenient for constant monitoring. What is more tragic is that these meters are gathering information but no reports can be generated – we would all just love to know (a) where our electricity went and (b) peak periods. I wish the designers would start focusing on this in the next generation of meters. What do I mean? Modern technology is cheap – so what would it cost to make a device to monitor (i) the high current trips e.g. stove/cooker (ii) geyser, the lower current trips (iii) plug points and (iv) lighting. By utilising the information the home user can determine individual consumption and act conservatively. These devices are available as third party add-ons but the point is, we already have a meter – use it. If it costs $100.00 more so be it. The entire distribution board to modern housing should be re-evaluated to streamline more efficient usage.

[GARD]

Energy Crises – Phantom power

Your computer, audio equipment, television receiver, monitor and cell phone charges are phantom hoggers of power. It is significant to note that only with the increased popularity of switched mode power supplies have these low current or standby power circuits come under the light – first generation equipment had an on off switch isolating mains power entirely, also eliminating any fire or safety concerns. In a typical house one may find up to 15W of power been dissipated unnecessarily every hour! 15 x 24 x 31 = 11kW over a 31 day month. Domestic users seldom think of the consequences when leaving their equipment on standby, besides it being a possible fire hazard.

Would it not be nice if the cable or satellite decoder be able to still decode signals when switched off, the low current receiver running off a standby battery for 24 hours?

In fact there are power strips designed to power off entirely if the current consumption drops below a predetermined limit. In many instances the home user has their TV, decoder and Audio running off the same outlet. Unfortunately the decoder has to always have standby power to decode an incoming data stream, sometimes to switch you off when you haven’t paid your subscription. Imagine that, keep it on so we can switch you off.

Frankly, a lot more can be done to reduce unnecessary wastage.

The Energy Crises – Different strokes for different folks

A common problem in society today is that the wealthy waste more. The wealthy are also becoming more energy conscious and can afford the trends we follow today to make our lives more comfortable but not at the expense of switching off power to save. Solar panels, solar heaters, inverters, storage batteries all cost money. The wealthy can also afford well-points, boreholes and water cleansing systems.

Here’s the thing though, the poor may be the biggest hoggers of energy because they are not educated enough. Using a stove plate as a heater is certainly not unheard of but is perhaps one of the biggest energy wasters known to man. Stealing power from the utility company is a common occurrence. So is death through the stealing of high energy power lines, incorrect wiring and not understanding transmission lines. Utility company employees often get paid big salaries because they are often highly trained individuals. Someone has to pay for the replacement of power lines, transformers, steel and of course, the medical bills. Cutting off the buyers will reduce this utter wastage. At present it certainly looks as if crime does pay.

The energy crises – to conclude

We really have become more aware of our own environment and the impact of power shortages but most often forget that it is the small changes in our own behaviour which produce the most favourable results. By monitoring these changes we can easily save up to 20% of our energy consumption with or without solar, wind or unscrupulous snake-oil devices added to the power chain. After all, the most cost saving device in our quest to reduce costs is the simple on / off switch. Becoming more aware of what you use and yes, more importantly where you use it, can make a huge difference to reduce wastage in our rather gloomy future of going back to the dark ages.

The energy crises may be caused by the utility companies lacking vision or under-pricing their commodities for too long, the reality is manufacturers of consumer products should be applying more thought into power saving than over-investing in petty technology.

[GARD]