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Things Network Gateway Diy Build

What is the Things Network

The Things Network originated in Amsterdam, Netherlands in 2015.

The idea was to create a crowd funded Internet of Things network, that was open to the public.

The network uses LoraWAN spread spectrum wireless technology to enable data from environmental sensors, to get onto the Internet.

The network has quickly expanded through crowd funding and volunteers installing their own ‘Gateway’ devices.

The Gateway devices receive data that has been transmitted from sensors, and puts that data onto the Internet cloud.

Sensors can include pollution monitoring devices, Smart Parking detectors, flood warning sensors etc.

The LoraWAN that I mentioned is the wireless technology that allows the transfer of data from the sensor (which might be in a field a mile from the Gateway), to the receiving Gateway device.

LoraWAN Characteristics

Lorawan is suitable for applications that only require small amounts of data to be transferred at a time. Therefore LoraWAN would not be suitable for transmitting video from a CCTV camera (WIFI would be more suitable).

Data transfer is also quite slow.

What LoraWAN excels at is allowing small amounts of data to be sent over relatively long distances (such as 10Km), while consuming very low battery power.

The good communications range, and low battery power consumption make it ideal for the Internet of Things, or IOT for short.

To start using the Things Network, there are a few options available.

Firstly you can buy a ready made indoor Gateway that the initiators of the Things Network have now manufactured.

A second option is to buy a Gateway designed for commerical LoraWAN use. These Gateways are often designed for outdoor use, and feature weatherproof construction.

A third option to get onto the Things Network, if there is no local Gateway within range, is to build your own Gateway.

There are a few options and ways to build a Gateway, including using an RF board from RAK Wireless.

The option that I used to build my Gateway, uses an 880A LoraWAN Concentrator board from IMST of Germany.

The RF Concentrator board is controlled and connected to the Internet via a Raspberry Pi.

Full details for construction are given below.

Building the Gateway

For beginners to building their own gateway, I would recommend joining, or founding a local Things Network .

The Lorawan Gateway that I am going to describe here, is designed to operate on the Things Network, however other lora networks can easily be installed.

The main components that you will need are:-

1) A Concentrator board from IMST of Germany. The Concentrator board is the wireless communications part of the system, responsible for receiving the wireless data signals, from the remote environmental sensors (Air quality sensors etc).

2) A small computer to store the software that controls the Concentrator board. We are going to use the UK designed Raspberry PI 3.

A Micro SD Card, for holding the software used by the Raspberry PI.  A small 4 GB card is fine.

3) A suitable Antenna (or Aerial), with pigtail connecting cable.

4) A suitable 2 Amp rated power supply, with a micro USB connector.

5)  7 Female to Female connecting leads, suitable for raspberry PI.

4) A suitable case, to house the components.

The first thing I need to make you aware of is the risk of static electricity, to your IMST ic880a Concentrator and Raspberry PI.

Static can damage the sensitive electronic components, therefore it is advisable to take precautions, such as not touching the board components, and wearing an anti static wrist strap.

The first thing you need to do is to format the micro SD card, that will be fitted to the raspberry PI, to hold the gateway software.

The SD card association has a free piece of software, for Windows PC and Mac, to do this. My card was already formatted, so I skipped this step.

The next step is to burn the actual software that will power your gateway, onto the Raspberry PI.

To do this, I used https://etcher.io/    

I first installed Etcher onto my  linux desktop computer. As most people use Windows PC, or Mac, you will need to find a suitable alternative to Etcher.

I also downloaded the operating system needed to run the Raspberry Pi, which is called Raspbian Stretch Lite , onto my desktop PC.

Put your micro SD card into your computers micro SD card reader. If your computer (like mine) does not have a card reader, then external USB plug in ones can be purchased cheaply (I got mine from my local Asda supermarket for £6).

Fire up Etcher, or whatever card  burning software you prefer, and select the copy of Raspbian Stretch Lite , that you previously downloaded to your PC.

Follow the instructions, and burn the operating system software onto the micro SD card.

Once you have successfully burned your Raspbian Stretch Lite, onto your SD card, insert it into the Raspberry Pi (the slot is on the underside of the Pi).

The next thing to do is to connect your Raspberry Pi to a suitable monitor (I used a TV, that had a HDMI connection), and also connect a USB keyboard, power supply, and mouse.

The power supply should be 5 Volts DC, and Raspberry Pi power supplies are widely available. I used a USB phone charger, with 5 Volts output, and a current rating of 2000mA.

Boot up your Raspberry Pi (connect the power), and you will see lots of computer code scrolling across your screen (if you have done everything successfully, so far).

When the Raspberry Pi asks you for a user name and password, use the following default ones (the  bit after the  ‘ : ‘ ).

Username: Pi

Password: Raspberry

After you have successfully logged in, type:

 sudo raspi-config

Numbered options will now hopefully be on your monitor screen.

Select [5] Interfacing Options, and then P4 SPI

Then select [7] Advanced Options , and then [A1] Expand Filesystem.

You now need to exit the raspi-config utility, either by hitting the ‘CTRL’  and  ‘X’ keys, or by typing sudo reboot

Next you are going to Configure the locales and time zone.

Type this in, to set the locales, and follow instruction.

sudo dpkg-reconfigure locales

Next, type this in to set time zone.

sudo dpkg-reconfigure tzdata

The next stage is to update the raspberry Pi software, do this by typing:

sudo apt-get update

Then install any upgrades to the operating system software, by typing sudo apt-get upgrade

Next we are going to install Git , which is needed to be able to download the Things Network software from Github.

Type:

sudo apt-get install git

The next step is to create a user called TTN (the things network).  This user will eventually replace the default raspberry pi user, which we will delete.

sudo adduser ttn

Then:    sudo adduser ttn sudo

Logout, by typing logout

Once you have logged out, log back in using the user name and password that you have just set up, when you added a user.

You can now delete the default Raspberry Pi user, by typing

sudo userdel -rf pi

Set the WIFI  SSID and password details, which can be found on the back of your home router / Hub (usually).

To set the WIFI details type

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf 

Once you have typed in the above text, you should see some code on the screen. Add the following to the end of the existing code, making sure that you enter your SSID and password details, in place of the shown text.

network=

{
ssid="The_SSID_of_your_wifi"
psk="Your_wifi_password"

}

Now we are going to clone the installer from Github. This will download the software which runs the gateway, from the Github repository.  Type each of the following three code lines into your Pi, one at a time, hitting the return key after each line of code.

  git clone -b spi https://github.com/ttn-zh/ic880a-gateway.git ~/ic880a-gateway
  cd ~/ic880a-gateway
  sudo ./install.sh spi

Identifying the LoraWAN Gateway

The software will give the gateway the default name of ttn-gateway.

This however may need to be changed, to prevent issues with other Things Network Gateways within wireless range.

Wiring it Up

The next step is to connect the  Concentrator board, to the Raspberry Pi, and also connect the antenna.

The components including the antenna should be mounted in a protective box,  and the antenna connected to the Concentrator board.

It is very important that the Concentrator board is not powered up, with no suitable antenna connected, of damage could occur to the board.

Once the antenna is connected, then the next step is to connect the Concentrator to the Raspberry Pi.

Connect using female to female connecting wires, as follows:

iC880a Concentrator pin Description RPi physical pin
21 Supply 5V 2
22 GND 6
13 Reset 22
14 SPI CLK 23
15 MISO 21
16 MOSI 19
17 NSS 24

IMPORTANT DISCLAIMER:

It is important that you identify the correct pins, by referring to the manufactures data sheets (Both IMST & Raspberry Pi).

We accept no liability for loss or damage caused, by following these information only instructions.

For help, and to learn more about the Things Network Gateway, or what the Things Network can do, why not get in touch with me.

@acraigmiles

www.craigmiles.co.uk

Craig Miles (C) 2018 -2019 , all images and content, unless stated separately.

Featured

Preventive Maintenance For Electric Motors

Preventative Maintenance

Preventive maintenance programmes  are the key to reliable, long-life operation of electric motors.
Whilst AC Induction Motors are particularly reliable in service, almost all electrical equipment requires periodic planned inspection and maintenance. Planned preventative maintenance ensures electrical motors, and starters are kept in good working condition at all times. This is critical for businesses that rely on electric motors. A scheduled routine of motor inspection should be carried out throughout the motor’s life. Periodic motor inspection helps prevent serious damage to motors by locating potential problems early.

Periodic Inspections

Planned electric motor maintenance programmes are designed to help prevent breakdowns, rather than having to repair motors after a breakdown. In industrial operations, unscheduled stoppage of production or long repair shutdowns is expensive, and in marine shipping environments, a potential safety issue. Periodic inspections of motors are therefore necessary to ensure best operational reliability.

Preventive maintenance programmes require detailed checks to be effective. All motors onsite (factory, ship etc) should be given their own individual identification (ID) number and have a record log. The record log is usually computerised these days. The motor records kept should identify the motor, brand, inspection dates and descriptions of any repairs previously carried out. By record keeping, the cause of any previous breakdowns can help indicate the cause of any future problems that might occur.

All preventative maintenance programmes should refer to the equipment manufacturer’s technical documentation prior to performing equipment checks.

There are simple routine maintenance checks that can be applied to three phase induction motors, which help ensure a long service life to a motor. 

The Simple checks that can be carried out, include a review of the service history, noise and vibration inspections. Previous noise issues could for example be due to motor single phasing. Previous vibration may have been due to worn bearings, which allow the Stator to turn. Other checks include visual inspections (damage and burning), windings tests (insulation resistance & continuity), brush and commutator maintenance (dc motors) and bearings and lubrication.

Inspection frequency and the degree of inspection detail may vary depending on such factors as the critical nature of the motor, it’s function and the motor’s operating environment. An inspection schedule, therefore, must be flexible and adapted to the needs of each industrial or marine environment.

(c) Craig Miles 2019.  craigmiles.co.uk

For bespoke electrical training with Craig, call  +44 (01522) 740818

Featured

Railway Global System for Mobile Communications GSM-R

Railway Global System for Mobile Communications GSM-R


The railway Global System for Mobile Communications is also known as GSM-R & ‘GSM-Railway’.
GSM-R Global System for Mobile Communications) is an international standard, covering railway communications.
It is a sub-system of the European Rail Traffic Management System, or ERTMS .
ERTMS is used for communication between trains and the railway control centres.
The ERTMS system is based on the EIRENE – MORANE standards specifications.
The EIRENE – MORANE specfications guarantee that the system will operate, at train speeds of up to 310 mph / 500 kph, with zero communication loss.
Communication Security
GSM-R offers secure voice and data communication amongst railway staff.
Users include train drivers, engineers, station controllers etc.
Communication security is important, both for commercial and security reasons.

Communication Hardware
Components of a typical GSM-R include the base station, mobile units installed in trains, and handheld units.
Antenna masts, connected to the base station are installed close to the railway track.
Tunnels present a communication challenge, due to blocking and attenuation of the RF signals.
The solution used, is to either use a directional ‘yagi’ antenna, directed through the tunnel entrance, or to use a ‘leaky feeder’ type antenna.
A Yagi antenna when used as a transmit antenna, directs most of the Rf power in one direction, rather than in all directions.
The Yagi antenna works similarly, when operating as a receive antenna, in that it receives most of the signal from the direction it is pointing in. A tv aerial on a house roof is a common example of a receive Yagi.
The other solution for tunnels, is the ‘leaky feeder’ antenna.
The leaky feeder is like a long piece of coaxial cable, which is designed to emit & receive RF (Radio Frequency) signals along its length.
This allows communications to take place in tunnels and underground stations.
The Leaky Feeder antenna is used in underground stations, where radio communications are required.
The advantage compared with the Yagi antenna, in such locations is that leaky feeders can be positioned round tunnel bends.
As Yagi antennas operate on frequencies that provide ‘line of sight’ signal transmission, bends will affect the signal path, attenuating them at best, blocking them at worst.
The spacing distance on the surface between the base stations, is 4.3 – 9.3 miles (7-15 km).
The system is built with high levels of reliability and redundancy built in, and if communication is lost, the train will stop.

The GSM-R specification standard forms part of the European Rail Traffic Management System, or ERTMS.
The ERTMS is comprosed of the following parts:
European Train Control System (ETCS)
Global System for Mobile Communications – Railway (GSM-R)
European Traffic Management Layer (ETML)
European Operating Rules (EOR)
Operating frequency band

GSM-R uses similar frequencies to the public mobile phone (cell phone) servcice, in most regions, namely around 900Mhz (E-GSM) & also at 1800 Mhz (DCS 1800).
The exact frequency used by Railway operators, is dictated by national and regional regulation bodies, but the 900 Mhz & 1800 Mhz bands are used worldwide.

Featured

Induction Motor Servicing Tips For Ships & Factories

Induction Motor Servicing.

Induction motors are used widely in factories and on ships.

They are very reliable machines, but faults can develop over time.

That is why you need Induction motor servicing to be carried out.

Potential faults include burnt out Stator windings, worn bearings, and water damage which causes low insulation resistance.

This article covers tips on Induction motor servicing.

Safety & Isolation of supply of induction motors.

Correct electricity supply isolation procedures are critical for safety.

Taking a casual approach to electrical supply isolation can prove fatal.

Three phase Induction motors, typically operate in factories at around 400 Volts AC (Alternating Current).

Marine installations typically operate at an even higher 440 Volt Alternating Current (440 VAC).

It is important that no one works on a piece of three-phase machinery, such as an Induction motor unless you are qualified to do so.

On board ship, proper authorisation, such as a valid ‘permit to work’, signed off by a ships chief engineer, should be in place before carrying out any Induction Motor servicing.

On land seek authorisation from the responsible senior managers, with appropriate responsibilities for safety.

For work to be carried out aboard Ships, permission from someone such as the Chief Engineer is appropriate.

Once permission has been gained, and the appropriate paperwork issued, only then can work commence.

Certainly in the marine environment, and normally onshore as well, ‘locks and tags’ will be issued.

The lock is to ensure that once an isolator switch has been turned off, no one can switch it back on accidentally.

The ‘tag’ details who has isolated the supply, and is working on that circuit.

Only the person who has been issued with the lock and tag set, can remove them.

Double check that circuit is dead.

Don’t assume that just because you have locked and tagged the appropriate electrical isolator, that you are safe to work on a circuit.

The isolator may be incorrectly labeled, or even worse, you have taken someone else’s word for it.

Before you stick your fingers in, and potentially kill yourself, you need to use an appropriate device to check that the circuit is safe to work on.

Induction motor servicing can be dangerous, if proper procedures are not followed.

There are three possible devices that can be used:

  1. Test Bulb
  2. Multimeter / Voltmeter
  3. Line Tester

Firstly lets look at the test bulb as an option.

A test bulb with appropriate leads and clips attached, can provide indication of a live circuit, but has a flaw.

If the bulb filament breaks, then you could falsely assume that the circuit is safe to work on, with possibly fatal outcomes.

The second option is the Multimeter / Voltmeter which these days will probably be a ‘solid state’ digital type, rather than the older analogue types, which are commonly referred to as ‘AVO’s’ in the UK.

The Multimeter / Voltmeter being ‘solid state’ is more likely to be a bit more reliable than, a filament bulb tester. However it still may be broken, and you would not necessarily know. An example being the test probe wires may be ‘Open Circuit’.

The third option, the ‘Line Tester’, will provide the most reliable indication of whether a circuit is safe. Therefore this is the preferred option.

The reason that a line tester is safer is because it contains four separate Neon bulbs (some modern ones are LED).

The bulbs light up according to how high the voltage is, for example a 400 VAC supply would light not only the 400VAC light, but the lower voltage indicator lights as well.

So imagine that the 400VAC indicator bulb has broken.

The lower voltage indicator bulbs will still light up, for example the 230VAC and 110VAC indicator bulbs.

Therefore the engineer will still have an indication that there is voltage in the circuit, and can investigate further.

Before using a Line Tester you should use a ‘proving unit’. A proving unit is a small hand-held device capable of producing a voltage such as 250 Volts.

The Line tester can thus be tested using the proving unit, prior to testing a real live circuit.

To test the Line Tester the two probes are pushed against the Proving Unit which then produces a voltage.

This will be indicated by an indicator LED lighting up on the proving unit itself.

The Neon or Led indicator lamps of the Line Tester should also light up at the same time, to indicate the voltage being supplied.

Tips when changing bearings on Induction Motors

Bearings on Rotor

The bearings on an induction motor, allow the ‘Rotor’ to rotate inside the ‘Stator’ which surrounds it.

Over time they can become worn, which may increase noise and vibration of the motor.

Bearings are not usually adjustable, so replacement is required.

 

Importance of  Bearing identification code facing outwards.

When refitting bearings to an induction motor you will notice that the bearing itself has a code written on the one side of it.

This code is the product identification code, and is what you need to quote in order to order the correct replacement bearing.

Once the correct replacement bearing has been obtained, and is ready for fitting, ensure the following.

Firstly, that the bearing identification code is facing away from the Stator, and outwards towards the end of the motor shaft.

This will help you in the future, if you ever have to replace the bearings again.

The reason for this is that you can just remove the end plate of the induction motor, and read the bearing code easily, provided it has been fitted with the code facing outwards.

If the bearing code was facing inwards, then it is harder to read the bearing code, and might mean that the motor shaft has to be disconnected from its mechanical load.

This adds to the motor downtime, and hence has financial and productivity implications.

 

Ways to remove bearings from induction motor shaft.

The ideal way to remove an old bearing from the induction motor rotor shaft is to use a bearing puller tool.

Removal is then just a matter of fitting, the tool into position, and winding in the screw thread in a clockwise direction.

As this happens, the bearing is slowly pulled up and off the shaft.

If however you don’t have a puller, other methods, such as  using a metal bar to leverage between the bearing and the end of the shaft can be tried.

However this is not the way I recommend, and you do it at you own risk of injury and damage to the motor shaft.

 

Methods for fitting a new induction motor bearing.

Ideally you will have a hydraulic bench press, that you can use to put massive pressure down onto the bearing to ‘press it’ onto the shaft, in the correct position.

When using such a press, a number of precautions should be observed.

Firstly, ensure that you are fully competent to use the hydraulic press. Even fairly cheap versions are capable of exerting many tons of pressure, which can be dangerous to human health.

Secondly, ensure that the tube or sleeve that you fit over the shaft of the motor is only just wide enough.

The reason for this is that a wide metal tube (or sleeve) put over the motor shaft in order to push against the bearing, can damage it.

This is because too wide a tube will make contact with the plastic middle of the bearing, or the outer metal edge.

Both of these two scenarios are bad, because pressure applied to anywhere but the centre metal part of the bearing, will cause damage.

This damage can result in the replacement bearing being ruined, which defeats the object of replacing it.

Using a hydraulic press is the method that we would recommend, however this option is sometimes not available.

In particular to engineers working at sea in a marine environment, such as a cargo ship.

If you find yourself in this situation, then there are other ways to re-fit a replacement bearing to an induction motor.

One method is to take advantage of the fact that metals contract and expand due to cold and heat.

This method involves carefully wrapping up the Stator part of the induction motor in a polythene bag, and putting it in the freezer overnight.

This will very slightly shrink the size diameter of the bearing shaft.

The second part to the operation involves gently heating up a pan of engine oil, so that it is warm.

Obviously extreme care needs to be taken, so that either a fire is not caused by the oil igniting, or the engineer receiving burns while trying to handle the hot bearing.

Once the bearing is warm, the Stator can be removed from the freezer, and the warm oiled bearing should slip fairly easily onto the shaft.

The oil can then be wiped off the bearing with a non fluffy cloth, and motor reassembly can begin.

 

 

 

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Electric Morris Minor

This blog post is about my design suggestions for an electric Morris Minor.

There have already been some prototype electric Morris Minor conversions already, which I will discuss.

In addition I have designed alternative ways to successfully convert classic cars such as the Morris Minor.

History & background

The Morris Minor is a British car designed by Sir Alec Issigonis, that was launched in 1948.

The Morris Minor originally was produced with an 918cc Side valve Petrol engine, but this was replaced in the early 1950s by an Overhead Valve (OHV) engine.

The OHV engine was improved and its size increased during the remainder of its production. and the later models were 1098cc in cubic capacity size.

The standard Morris Minor had the engine connected to a four speed longitudinal mounted gearbox, attached at the back of the engine.

The gearbox output is connected to a long single drive shaft, which runs underneath the car.

The drive shaft connects the gearbox to the rear axle.

The rear axle incorporates a ‘differential’ which fixes the speed ratio, between the rotational speed of the drive shaft, and the rotational speed of the road wheels.

Therefore as the engine power is transferred via the gearbox and drive shaft, to the rear axle, it is a rear wheel drive car.

Any design for an electric Morris Minor, will probably stick with the rear wheel drive configuration.

The reason for keeping the electric Morris Minor as Rear Wheel Drive, or RHD for short, is engineering design simplicity.

The front suspension on a Morris Minor was advanced for a British car of its time (1948).

The front suspension used torsion bars, as the springs, and featured ‘rack and pinion’ suspension, that is still used in modern cars.

The shock absorbers are different to the type used in modern cars, and are known as ‘lever arm shock absorbers’.

To convert an electric Morris Minor into powering the front wheels, known as front wheel drive, would require major suspension modifications (unless hub motors were used).

This is because the original Morris Minor steering and front suspension system, would need a lot of component changes.

Of course its possible to make a front wheel drive Morris Minor, but more expensive, and also changes the cars handling characteristics.

If however you are hell bent on a front wheel drive electric Morris Minor then its possible.

My solution would be to use hub integrated motors.

Hub integrated motors consist of an individual electric motor powering each driving wheel.

For instance to create a front wheel drive Morris Minor, you would have two motors driving each of the two front wheels.

If you wanted to use hub motors, but to keep the traditional Morris Minor rear wheel drive configuration, you would fit the motors to the two rear wheels.

So let’s decide to stick to the original rear wheel drive layout for our electric Morris Minor.

There are four ways that you could configure the electric motor layout. This also applies to many other classic cars, which share the same basic layout.

Firstly, the original internal combustion engine can be removed, whilst leaving the Morris Minor gearbox, driveshaft and rear axle (Inc differential) in place.

An electric motor is then attached to the original Morris Minor gearbox.

Some electric motor conversions that use this layout configuration, are clutch less in design. The torque & high rev range of many electric motors mean that the car can be driven in the same gear for most of the time.

Other electric car conversion designs still incorporate a conventional clutch.

The advantages of retaining a clutch are better motor speed control, and more importantly more retention of the original Classic Car experience.

A second option for mounting the electric motor in your Morris Minor, would be by removing the gearbox and either mounting the electric motor at the front end of the drive shaft, and directly attached to its front end.

Or alternatively the drive shaft could be removed, and the motor mounted directly to the rear axle differential input shaft.

This second method of attaching the electric motor directly to the rear axle differential connection, has advantages and disadvantages.

The advantage is a saving of weight, by removing the drive shaft which runs underneath the car, from front to back.

Less weight is a good thing for performance of your electric car.

The disadvantage is that it makes it a bit harder to mount, than if you mounted the electric motor at the front end, and retained the driveshaft.

It is harder to mount, because you need to create a mounting cradle which attaches to the rear axle, and supports the weight of the electric motor.

Morris Minor Hybrid


You may well of heard of Hybrid cars.

If not, then let me explain what they are.

A hybrid car is a car that uses a combination of combustible fuel, such as petrol or diesel, and electric power.

A hybrid car might drive the wheels using an electric motor at low town speeds, and petrol at higher speeds.

Alternatively, the petrol (or diesel) motor could be used, if the battery was low on charge.

The use of electric motors at low speeds around towns, has obvious environmental advantages.

However you might also still want a traditional petrol motor for long distance trips.

My design for a Morris Minor Hybrid, keeps the petrol engine, whilst also adding electric front wheel drive.

The rear wheels continue to be driven by the Morris Minors petrol motor.

Whilst the front wheels are driven by ‘in-hub’ electric motors.

A simple solution would be to have a manual switch, to be able to select the drive system.

Alternatively an automatic electrically controlled system could be used.

I am currently considering the design for an automatic system, and will provide further details in the future.

Gearbox Considerations

If you want design simplicity for your electric Morris, then keep the original gearbox.

The electric motor is simply attached to the gearbox, in place of the original petrol motor.

This is done via a special adapter plate, and a coupler.

The potential problem with using the original gearbox is excess motor torque.

Vehicle Electric Motors produce a lot of torque at low RPM (Revolution Per Minute).

The standard Morris Minor gearbox was designed to handle a maximum engine torque of 60 lb/ft (81 N·m) at 2,500 rpm.

The above torque figure is for the most powerful Morris Minor, built from 1962 onwards.

The gearbox was upgraded in 1962, along with the engine size (to 1098cc from 948cc), and gained Baulk-Ring-Synchromesh .

To ensure that you do not suffer premature gearbox failure, it is important that you consult electric motor manufacturers datasheets.

For an ordinary road going car, this should not be an issue, if precautions are taken to select a suitable motor.

For those looking to upgrade their Morris Minors performance, then this is definitely a consideration.

Featured

Electric Alfa Romeo GTV Conversion

Alfa Romeo GTV History

The Alfa Romeo (916) GTV was produced between 1995 – 2004, with only around 40,000 GTV models, and a similar amount of the open top Spiders, being manufactured during the whole period. They did not produce an electric Alfa Romeo GTV.


Alfa Romeo GTV

Reasons For Electric Alfa Romeo GTV

Reasons to convert a petrol Alfa Romeo GTV, or any Alfa Romeo to electric are both environmental and performance.

Environment

The smaller engined Alfa Romeo GTV, that was available to the Uk market, still emits 220 grams of CO2.

Performance

The smaller two litre ‘twin spark’ engine produces around 155 BHP.

Its possible to create a higher performing electric powered car.

The decision to re-engineer my own Alfa GTV, to run on an electric motor, rather than the original petrol engine, which emits a high CO2 level of 220.

I will be improving and updating this blog post on a regular basis, so check back regularly.

Why am I doing this? – Well for starters there is the high CO2 level.

The car failed its MOT in December 2012 on emissions and a small hole on the underside inner sill.

The car was put into my garage shortly after, and almost forgotten about, until recently.

Although I have successfully managed to get the engine going, the car would need a new rear exhaust silencer, radiator (as in poor condition), and new cambelt and balancer belts (not a cheap job).

The last items, are the main reason I took the car off the road after it failed its MOT in 2012.

The belts need replacing every three years, or 36,000 miles according to Alfa Specialists, and mine were way over due (time wise).

A second reason for wanting to convert my Alfa Romeo GTV to be powered by an electric motor is performance, yes you did read that correctly.

The Alfa Romeo GTV came in two basic variants, four cylinder, and six cylinder (V6) petrol variants.

The original 2 litre four cylinder version that I have, is a fantastic high revving motor, with a unique Alfa Romeo 8 spark plug design.

However it gets overshadowed (unfairly in my opinion), by the tyre shredding V6 version.

My objective is to create an Electric Alfa Romeo GTV that has faster acceleration, than the V6 versions.

But aren’t electric cars those off looking slow things, that oddball eccentrics drive? Electric cars have come a long way in recent years, due to advances in technology.

Just look at the acceleration figures for a Tesla Car, if you have any doubts.

Deciding on Electric Vehicle Conversion Performance


My other project the Electric Morris Minor



Featured

Zigbee Technical Characteristics

Characteristics

Zigbee characteristics make it suitable for short range wireless communications.

It is based on the IEEE 802.15.4-specification, created by the Institute of Electrical and Electronics Engineers (IEEE).

The technology is used to create personal area networks, also known as PAN(s).

PAN’s are created using low-power digital radio tranceivers, using Zigbee technology.

 PAN’s are used in applications including home automation, data collection, and medical devices.

Zigbee is designed to be used in small scale projects requiring wireless connection.

Characteristics of the technology is low-power consumption and RF transmit power, low data transmission rate, and short communication range.

  • Developed by Zigbee Alliance
  • IEEE 802.15.4 based specification
  • High level communication protocols
  • Used to create Personal Area Networks (PAN)
  • Uses small low power digital radios
  • Typically used for home automation, medical device data collection, other projects requiring low power & low bandwidth
  • Conceived in 1995, standardised in 2003, revised in 2006

Features of Zigbee

  • Low power
  • Low data rate
  • Close proximity data communications
  • Wireless ‘ad hoc’ network (WANET), which is a decentralised type of wireless network.

Zigbee Advantages (compared with other WPANS, such as Bluetooth & WIFI)

  • Simpler
  • Less expenditure

Applications (typical uses)

  • Wireless light switches
  • Home energy monitors
  • Traffic management systems
  • Other consumer & industrial equipment, requiring short communication range & low wireless data transmission rate
Typical  Performance
  • 10 – 100 meters range (per device), based on line of sight
  • Range dependent on both power output & environmental characteristics
  • Long distance communication possible by passing data through a ‘mesh network’, which allows the data to transfer through ‘intermediate’ devices between zigbee nodes
  • Long battery life, due to low power consumption
  • Secure communication using 128 bit symmetric encryption keys
  • 250 kbit/s, which is suited to intermittent data transmissions, such as from a sensor or other input device.

Internet Of Things Consultant

The Internet of Things or IOT for short is the connection of machines, sensors and objects to the Internet cloud.

I can help your business with the Internet of Things by researching, designing and implementing solutions, tailored to your business.

LoRaWAN architecture and uses in Sensing

How to Build a Lorawan Gateway

Zigbee Technical Characteristics

What your Microwave Oven has in common with your WIFI

 

International Marketing lessons that McDonalds should have known before ‘Sundae Bloody Sunday’ Promotion

International Marketing

When I studied international marketing during my undergraduate degree in the mid 1990s, I learnt something important.

It is important to ensure that your brand name and advertising do not cause offence in some markets.

The case study we learnt was that of Toyota cars, who had produced a sports car called the Toyota MR2.

The original model MR2 was launched in 1984, but the name soon caused an unexpected issue.

You see ‘MR2’ when said out loud, sounds like something rude in French (basically Shit!).

Clearly no business wants their product to have this image, so the car was renamed for the French speaking market.

Now what has this got to do with yesterdays news about McDonalds in Portugal.

For those of you that didn’t read or see the news, McDonald’s has apologised  for accidentally causing offence with its ‘Sundae Bloody Sundae’ promotion.

For younger readers, and those without an Irish connection, the promotion sounded like ‘Sunday Bloody Sunday’.

‘Sunday Bloody Sunday’ happened in northern Ireland in 1972, and resulted in 14 deaths, by gunshots, during ‘the troubles’.

Due to the context of the deaths, it is still understandably a very sensitive matter for many people.

The point I am trying to get across in this article in international marketing  is that it is important to think internationally.

Thinking on an international marketing level was important for large business in the 1990s.

It is also now important for SME (Small & Medium Enterprises), due to the growth of the Internet.

Lessons to be learned

Personally I am surprised that a company like McDonald’s slipped up like this.

Normally they are experts in positive marketing of their products, and in creating a fun brand image.

Going forward I am sure they will double down on ensuring that promotions do not cause offence in other countries.

Conclusions and advice

Someone seems not to have checked that the advertising campaign would not cause offence outside of the local Portuguese target market.

Businesses should always check that they will not offend other countries that they currently operate in, or intend to in the future.

It is even more important now than it was in the 1990s, due to the Internet.

@acraigmiles

LPWAN

Main features of LPWAN Technologies

  • Low power RF technology
  • Low current consumption, therefore long battery life
  • Wide area coverage, compared with other technologies like Bluetooth Wifi.
  • Lower cost than mobile networks, such as 5G
  • Enable wireless connectivity of remote ‘field’ sensors to internet gateway devices.
  • A key component in the internet of things.
  • Suitable for devices and applications that require low speed data rates.
  • Not suitable for devices & applications requiring high speed levels of data transfer, such as cctv links. Wifi is a much more suitable technology for cctv links.

History

LPWAN is short for Low Power Wide Area Network.

The term was first introduced in 2013 for a technology designed for M2M communications, which is short for ‘Machine-to-Machine’ communications.

What is LPWAN

As a technology it provides a niche gap solution between mobile cellular (3G, LTE), and short range  technologies, such as Bluetooth, Wifi & Zigbee.

LPWAN is designed for machine communication rather than between humans.

Human communications consist of voice, video & data, and have different technical requirements to M2M.

Human electronic communications require high data rates and low latency (signal delay), while the user is moving around.

M2M requirements by contrast require low data transfer rates, infrequent transmission, and a low mobility requirement.

LPWAN technology is used by businesses to create their own secure data communications network.

Current LPWAN Technologies

It is available operating both on licenced radio frequency spectrum, and unlicenced radio spectrum.

Licenced Radio Spectrum IOT Technologies

  • NB-IOT
  • LTE-M
  • EC-GSM-IOT
  • Thingstream

Unlicenced Radio Spectrum IOT Technologies

  • Sigfox
  • LoraWAN
  • RPMA
  • Weightless
  • nWave
  • SAT4M2M
  • hiber
  • Telensa
  • NB-Fi
  • helium
  • MIOTY

 

 

 

 

 

 

Single Phase Transformers How They Work

Single Phase Transformers

Transformers are most commonly ‘step-down’ types.

This means that the voltage that comes out is less than the voltage going into the transformer.

The ‘transformer ratio’ of the winding’s on the input side ‘primary’ & output side ‘secondary’, determines the output voltage.

Example: 100 volts AC going in with a 10:1 (Primary / Secondary) winding ratio, would give 10 volts output.

  • Information about Single phase Transformers

There are two main types that you will come across.

Single Phase

&

Three Phase

The difference between the two types is that Single Phase have four electrical connections, whereas Three Phase have six.

In the case of a Single Phase Transformer, the four connections consist of two input connections, and two output connections.

The Three Phase types six connections, consist of three input connections, and three output connections.

Both single phase and three phase transformers will only work with Alternating Current (AC).

AC was invented by Nikola Tesla over 100 years ago, and is the dominant system used (as opposed to Direct Current (DC), for electricity transmission.

AC is the electricity that comes out of a wall socket in a house, in nearly all installations around the world.

Unlike Direct Current (DC) in which the polarity of the two connections stays constant (has a fixed + & -), AC voltage ‘Alternates’.

The ‘Alternating’ in Alternating Current (AC) means that the voltage in the two wires is constantly changing direction and level.

The picture below shows what is actually happening

AC Sine Wave

The picture above shows an AC Sine Wave.

As you can see, the ‘wiggly’ line travels both above and below the straight horizontal line.

The horizontal line represents the 0 Volts level, and below the line is minus volts, and above plus volts.

The two wires of a single phase transformer are connected in a fixed position, but the picture shows what is happening in each of the wires.

The peaks represent the peak voltage in one of the two wires, therefore if the voltage is at the peak in one wire, it is the opposite level in the other wire.

The ‘alternation’ of the voltages in the two wires happens rapidly and constantly.

The speed of change is called the Frequency, and is measured in Hertz (Hz)*.

*It is worth noting that on older pieces of British machinery such as Transformers and Induction Motors, you may find Frequency described as ‘Cycles’, rather than Hz.

In the UK and Mainland Europe the frequency of the mains electricity supply is 50Hz, whereas in countries like the USA and Japan, it is 60Hz.

This constant frequency of voltage change creates electromagnetic induction in the transformer.

Smart Factories

Condition Monitoring

Smart factories improve automation and efficiency compared to traditional factories.

Efficiency is increased both through process decisions being made without human intervention.

Efficiency is also increased by using sensor data to monitor the condition of machinery, such as three-phase induction motors.

Monitoring of induction motors, can include vibration sensors, which monitor the condition of the rotor bearings. A worn  bearing will cause increased running friction, which can be monitored by attaching external vibration sensors to the motor casing.

Other conditions that can be monitored on a factory induction motor, are rotor speed, Stator winding temperature, single phasing faults,  current drawn and voltage levels.

Other uses of smart factory monitoring systems, are the monitoring of the production process.

 

Smart Factory  Buildings

The factory building that houses the operational machinery, also forms part of  smart factories.

Automated temperature control has been around for years, and is also used in almost every home too. Its called an automatic thermostat!

Smart buildings can adapt the heating control automatically, by sensing where heat is needed in the factory building.

For example sensors, can detect if people are working in a particular section of the factory.

The sensor data is used to only heat the parts of the factory that require it.

The use of sensors can also be used to switch lighting on or off, depending on actual real-life demand for light, within sections of the factory.

Smart control of lighting and heating systems within the factory environment, reduces the variable costs of the the business operation.

 

 

 

 

 

 

 

What your Microwave Oven has in common with your WIFI

Radio Waves

What does your microwave oven have in common with your WIFI connection?

The short answer is radio waves.

A microwave oven operates by bombarding the food with high frequency radio waves.

A device called a Magnetron bombards focused electromagnetic waves at the food inside the microwave Oven.

This works by heating the molecules inside the food, which are tiny in size. The food molecules are vibrated by the radio signals produced by the magnetron, which causes them to heat up.

It is actually electromagnetic radiation that is cooking your food.

This radiation is dangerous, which is why there is a grid with tiny holes in the microwave door.

The higher the radio frequency in the electromagnetic spectrum  the shorter is the ‘wavelength’.

Microwave ovens operate at a radio frequency of 2.45 GigaHertz (Ghz).

WIFI also operates around 2.45 Ghz, hence the connection between the two, in this articles title.

As previously stated, microwave ovens have a grid incorporated into the door, which contains small holes.

These holes prevent the electromagnetic radiation produced by the Magenetron, from escaping out of the microwave cooking area.

The metal grid with holes in, is important because being cooked is hazardous to human health!

So is my WIFI also dangerous?

Whilst research has been carried out, and some people claim it is, you will not be cooked!

The reason for this is ‘RF Power’ level.

When RF (Radio Frequency) engineers work near very high power radio transmitters they use RF radiation monitoring devices, and appropriate protective PPE.

Whereas you will not get RF Burns’ using a handheld walkie talkie, or mobile (cell) phone.

Its down to RF Power levels being emitted from the antenna system.

Whilst RF frequency also is a factor, lets ignore that for the purposes of this blog article.

WIFI signals are low power radio signals, at a low RF Power. Hence you don’t get cooked, standing next the the wireless router.

Hopefully now you understand the answer to what does your microwave oven have in common with your WIFI connection?

If not, ask me a question, so that I can clarify and expand your knowledge.

(c) 2019 Craig Miles Craigmiles.co.uk

Why not hire me!

 

 

 

 

Deciding on Electric Vehicle Conversion Performance

Performance of the Electric Vehicle conversion is my next consideration in the electric Alfa GTV project.

The standard 2 litre ‘twin spark’ engine in the factory standard Alfa GTV, propels the car to sixty miles and hour in just over 8 seconds.

Increasing performance is one of my objectives for the project, in addition to making the car more environmentally friendly.

I have decided that I want to increase the performance of the car, without going to extremes.

The fastest electric Tesla car is capable of reaching 60 miles an hour in just over 2 seconds!

I don’t want that kind of performance for two main reasons.

Firstly is cost. The more performance you wish an electric car conversion to have, the more it will generally cost (unless you can obtain secondhand parts cheaply).

Even if I was given a large Tesla electric motor, then I have to make it fit.

The Alfa Romeo GTV has a sophisticated multi link rear suspension system, which takes up a lot of room at the back of the car.

The Alfa Romeo (916) GTV is front wheel drive.

Therefore if you wished to mount a powerful electric motor at the back, and create a rear wheel drive car, it would require serious suspension modifications.

Serious suspension modifications are expensive!

I have therefore decided to go for an electric car conversion, that keeps the original suspension, engine and gearbox layout.

Keeping the original component layout will help maintain the weight distribution, and therefore the cars handling.

Of course keeping the original engine layout does not mean keeping the original engine.

The original petrol engine will be replaced with an electric motor.

Secondly, is the cars characteristics, which I wish to maintain, such as feel and handling.

To maintain the cars handling, careful consideration is being made of what weight is being removed and added.

The aim is to end up with an electric conversion, that has similar weight balance to the original specification.

An electric motor generally weighs less than an internal combustion engine.

But an electric conversion has the added weight of much heavier batteries.

You also lose weight by removing no longer needed items, such as the exhaust system.

The Alfa Romeo GTV exhaust system is heavy, and can contain up to four catalytic converters in some model versions.

I am going to weigh components as they are removed and added.

The aim of weighing the components, is to replicate the original weight distribution of the GTV.

One of the factors in performance is the cars weight, so if the car can be made slightly lighter, then that will help with acceleration.

A useful calculator for working out performance is on this website .

The website link above lets you enter the motor power in KW, the weight of the car, drive type (FWD or RWD) and transmission type.

It then calculates the 0-60 MPH acceleration time.

Of course wind resistance will be a factor, and a tall square vehicle will have a higher ‘drag coefficient’ than a low sports car.

My objective for the electric Alfa GTV project, is a 0-60 of six seconds.

This is about 2.5 seconds than the original petrol engine could produce.

According to the website, I will require about 175 KW power at the flywheel.

Next: Electric Motor Choices