Search This Blog

Saturday, May 1, 2021

Water & Electricity Saver for Instantaneous Heater

Important Note & disclamers :  Modification to any water heater is extremely dangerous.  It should only be done if only you are familiar with the device as there are many accidents involving electricity electrocutions if the modification is not done properly.  

The alternative and safe way to achieve the same result is to turn on the tap to switch on the instantaneous heater on a high setting for a few seconds  and then turn off the tap for the water in the heater to be warmed up.

This article is just for reference only.  The author assumes no responsibility whatsoever.

Introduction

In tropical countries,  electrical instantaneous heaters are often used.  This is because residents often need only heating for showers. These heaters do not occupy space. They often save water and electricity as compare to water storage heaters. Also, they are less than 3 KW and can be powered from the usual 13 Ampere power point. This article will describe a device that will further save some water and electricity.

Working Principle

Every Instant water heater has a small heating exchanger. It gets power through a set of micro-switches that select 2 or more heating elements to warm up the water. The modern ones nowadays use electronic TRIACs to control the heater.

 

For these heaters to heat up the water, one needs to first set the selector switch and turn on the water. The water pressure sensor will pick up the pressure and actuate the micro-switches. These switches will turn on the appropriate heater element to heat up the water in the exchanger. The schematic circuit diagram of Aerogas Elegance water heater is as shown below:

 

Water & Electricity Savings

To heat up the water, water must first flow through the heater for the pressure sensors to pick up the pressure. Water amounting to 1.2 litres will be wasted before warm water can flow out of shower head. At the same time, electricity amounting to about 8 Watts-hr will also be wasted. Assuming a household of 4 persons might take 6 showers per day,  a total of about 2,600 litres of water and 17 kWh of electricity can be saved per year. This might sound to be petty savings for one household.  But it is still a sizable saving for a township of more than 10,000 families.

 

How Water and Electricity Can be saved?

To save, one can use this electronic gadget called “Trigger Delay Time Off Timer” as shown in the following:

 

Circuit Description

The gadget operates on 220V AC supply.  The delay time off is triggered started by a button.  The complete schematic diagram is as shown below


For the gadget to work in the seconds range, the default variable resistor must be changed from 50K ohm to 5K ohm. As the heater will consume 9-13 amperes, it is also necessary to add an external relay. The built-in relay has only a 10 ampere rating.

This gadget has an opto-coupler to isolate the trigger button from the 240V Supply. But the button is linked to the neutral terminal of the 240V supply. It does not offer complete electrical isolation. It will be ideal if there is an isolating transformer for electrical isolation.

 Wiring up


Safety Precautions

Important Note: Wiring up will need one to know about safe use of electricity. A wrong wiring such as wrong polarity connection by interchanging the line and neutral wires for example,  can cause shower head or water to be alive. It can be dangerous causing electrical shorts and execution.

Whenever possible, use only push button of plastic material. If metal material is used, its body must be connected to the earth.  Only waterproof push button can be used.

Further, one should always test the integrity of the heater’s earthing system. The method described in this article can be used to test theearthing.

To further protect the heater, it is recommended to install the following:

1) A Thermal fuse to cut the supply to the relay when the heat exchanger reaches an abnormal temperature of 85oC. This temperature is about twice the normal operating temperature of the heat exchange. The thermal fuse must be of non-metallic type.  It is to be attached to the heat exchanger for proper operation.

2) A surge diode is to protect the relay contacts from electrical arc welding. This will prevent the relay from welding. Heat exchanger is wire wound. They cause inductive current that could cause the relay to use and weld together. The surge diode will clamp the voltage to less than 328 Volts. This is the breakdown voltage of the 400V surge diode.

For information, the thermal fuse and the surge diode would cost less than USD$1/= each. It is good investment for a piece of mind.



 

 

Friday, April 2, 2021

Alternative Olympic Football Site

Plesae click "I accept" at the bottom of the page if the video does not play automatically After that Select "Olympics" & the streaming game to watch

Friday, January 1, 2021

1 January 2021

The Chairman of Chinese Communist Party (CCP),  Mr. Xi Jin Ping called on his people not to waste food. He made this call in August after there was a heavy flood in China. The flood covered large area of agricultural land in China. The flood destroyed not only the properties but also lot of crops and food.   

The Communities in China responded with much enthusiasm.     People from School children to dinners, came out to support the campaign. The restaurants and the various communities and organization are receptive to such call.   But, the western medias were not as enthusiastic.  CGTN, the Chinese media was of the view that these western medias did not report the campaign in a fair manner. It claimed that China has not made any new laws.   Instead,   China was only trying to raise public awareness about not to waste food.

Some restaurants had taken the opportunity to make some money.  One restaurant in Hunan Changsha installed weighing scales in its restaurant. It has sign board advising what meal the customers should order for their weight.

The Organizations and  the Associations are not ready to drop behind.  For example,  this Food Catering Industry Association in JiangSu  arranged a seminar recently. It took the opportunity to get customers to eat in Nanjing.
 

 

Tuesday, December 15, 2020

Interesting Notes About the US Election 2020

15 December 2020

United States has a Presidential election on 3 November 2020.  It was  an election between Mr. Joe Biden and Mr. Donald Trump.   Some estimated that more than 150 million Americans had voted. The turn out was one the most in recent American history. Many said the large turn out  was because of  Donald Trump.

The initial vote counts indicated Joe Biden was the winner.   He had 290 electoral vote and Trump had only 232.  Also,  Joe Biden had 80 millions vote count and Trump, around 70 millions.

There were many lawsuits about frauds in the election.  Some suits was lodged as early as 6 November.  The Pro-Trump group and Trump Campaign Teams submitted no less than  50 lawsuits.   The Courts rejected almost all of them.    

Trump’s lawyer team, led by  Mr. Rudy Giuliani also  filed lawsuits.   They were also not quite successful.    Ms Sidney Powell, a private lawyer, helped to lodge a suit around end of November in the court of Georgie County.  Her  request for decertification of election result was denied by the Court.   But,  the Court accepted her other requests,   such as  carrying out a  forensic study on the voting machines.  Also granted by  the Court was the scrutinizing of CCTV video footage on the night of the ballot counting.   Sidney also filed lawsuits later in the Courts of Michigan, Arizona, and Wisconsin.  She had almost the same results. 

The alleged frauds were mostly about the misuse of the electronic voting machines.  The suits were also about the fraudulous votes in the mail-in ballots. While  little or no evidence were found in the mail-in ballots, there were good progress made in the findings of the forensic studies.  

The result of the  forensic study carried out at Antrim County of Michigan found its way to the 13th Circuit Court on 14 December 2021. This Circuit Court had scheduled a Trial to be  held sometime next April 2021. Understand the Arizona Senate Judiciary Chairman had announced the authorization of a full forensic audit on Arizona’s voting machines and software.

All of a suddenly, the World Wide Web was full of many stories about the frauds found in voting machines.  One of them is shown here.

 


Understand the Electoral College has affirmed Biden’s win.  The next in the process is to send the result of the Electoral College's Vote  to the House for further processing.   The House and Senate will  debate and vote again if there is one House Representative submit his objection in writing.  As there is trial pending in the 13th Circuit Court,   the members of the House & Senate might want to consider to wait for the Court's result if so permitted under the US Constitution.

Disclaimer:  This article is a short summary of what were reported or posted in Twitter and other MSM.                      The information might not have been verified.

Friday, July 24, 2020

Repairing Faulty Push Button in a PC Mouse

 24 July 2020

The left button of the mouse was not working. To fix the mouse, one would have to open up the mouse, cleaning the push button contact which might have bad electrical contact after years of usage. This video tells how to clean the contact.

To Reduce the Fan Noise in the PC Power Supply Unit

23 July 2020

Some power supply unit for the PCs have very noisy fans. The good one will come with a thermo controlled fan; the cheaper ones usually have this omitted especially when they are made for Bit-Coin mining machines. The solution is either to change the fan or have a fan speed controllers installed. This video describe how best to carry these works.
\
 

 Update:

The circuit in the video used IRF 634 which has a rated voltage of about 500V.  A cheaper euivalent is IRF 744 rated at 250 V.   The components are listed as shown


The veroboard layout of the component and its connection is as shown below



 

Monday, July 20, 2020

Do not Touch Any Power or Lamp Pole when Wondering in Flood Waters

20 July 2020

Floods are everywhere during this raining season.   They are in Japan,  India, China,  Indonesia,  Malaysia and many other parts of the ASIA.  In Japan, we have Typhoons.  In China and South East Asia,  we have the Monsoons and in India,  we have the heavy rain.   Some floods are not actually caused by heavy rain. Breakdowns in embankment of rivers and dams are often the cause in large area floods.
It is unfortunate to learn people died in floods. Some drowned; others electrocuted by high voltage electricity. Although lesser people died this year as compared to previous years. One thing we can help is by educating people to kick the habit of holding or touching the power or lamp poles in a flood.

This video was prepared using incidents happening in China recently.  It tried to explain why it is dangerous to hold on or touch any power or lamp poles when wondering in flood water.   Traffic poles are also dangerous in a flood.
 
 

Sunday, May 3, 2020

New MiTV model


According to a Chinese article, ZNDS,   Xiaomi China has actually  registered with the local authority 5 models of MiTV5 in Feb/Mar 2019 including a 65" MiTV5.  They are namely

1.  MiTV 5A  65"
2.  MiTV 5S  45"
3.  MiTV 5A 55"
4.  MiTV 5S 55"
5.  MiTV 5S  43"


The details of the registration are as followed:


https://1.bp.blogspot.com/-cICRdFmnhhM/XYRhJ0OO2jI/AAAAAAAAEKw/CnSUSJrFaI8W3pEs64EDimZbwiEwkF2AACLcBGAsYHQ/s1600/2019-09-20_13h08_33.jpg


Hopefully,  Xiaomi will introduce the Global version of 65" MiTV5 to satisfy those  user who are looking  for larger sized MiTV.

Simple and Easy Way To Backup Photos, Movies and Documents from handphones

 2 December 2023 In the past,  we used iTunes when we wanted to transfer or backup our photos,  movies, and documents from iPhones or Androi...