lorawan integration

LoraWAN Advantages for IOT

LoraWAN advantages for the Internet of Things, also known as IoT, are discussed in this article.

LoraWAN is a useful technology for business process improvement.

LoraWAN is a low data rate, low power, long-distance wireless technology.

The ‘Lora’ part of the name, stands for ‘LOng RAnge’.

LoraWAN is designed for Internet of Things (IoT) uses.

LoRa technology offers bi-directional communication, end-to-end security, mobility and localisation options.

Lora typically operates within license-free ISM (Industrial, Scientific, Medical) radio frequency bands located below 1 Gigahertz (GHz).

Operating in the ISM frequency bands, allows anyone to build a LoraWAN network, without the cost of Ofcom (in the UK) spectrum operating licences.

Lora technology provides a very long-transmission range, compared with Wifi & Bluetooth etc, while using exceptionally low power consumption.

There are of course IOT applications that are better suited to other wireless technologies, such as Wifi.

LoraWAN can only transmit small amounts of data at a time, so is not suitable for streaming video for example.

Lorawan Advantages are listed below:-

Long-range and deep penetration

LoraWAN is good at penetrating into buildings, or even underground. Therefore Sensors can be located indoors, outdoors and even underground, and still be able to communicate with the receiving Gateway device.

Distances of up to 50Km can be achieved in open areas and up to 10km within a town or city.

Low Power

LoraWAN’s advantage for IoT is offering low data bit rates, which results in low energy consumption.


Environmental Sensors such as Smart Parking or Soil sensors are designed with Lora technology, to send small amounts of data when required.

How often the small amounts of data are sent can be designed to be event-driven or at a scheduled time period.

This enables battery life to last for up to 10 years.

High Network Capacity

Lora uses an adaptive data rate and features a multi-channel multi-modem transceiver in the gateway device.

This allows for simultaneous messages to be received on multiple channels.

Therefore a LoRaWAN network has very high capacity and scalability options..

Open Standard, unlicensed band

The LoRaWAN specification is supported and maintained by the LoRa Alliance.

LoraWAN mostly operates in the licence free ISM (Industrial Scientific Medical) bands.

In Europe the frequency is 868MHz, and 915 in the USA etc.

The advantage of LoraWAN operating in an ISM band is that there are no expensive licence fees to be paid to local regulatory bodies (Ofcom in the UK, for example).

A potential disadvantage of using unlicenced frequency spectrum is interference from other users.

Security

Lora has AES-128 encryption built in as standard.

Ease of Installation

As Lora connected Sensors consume only tiny amounts of power, they can run from batteries for a number of years. This makes installation simple, as time-consuming & expensive cabling isn’t required.

Uses of LoraWAN

LoraWAN is great for a number of application areas. Some of these are listed below:

Smart Agriculture

Smart agriculture is a term that refers to using sensor technology monitor environmental factors.

Environmental factors that are monitored include soil Ph, moisture content, water levels etc.

The data from the sensors is fed back to the internet or local server, for analysis and processing.

As Lora is a two-way technology, it can also be used to send data commands out to equipment in the fields, as well as receive data.

This could for example allow water valves to be remotely controlled when the sensors detect a field that needs watering.

Smart Cities

Smart cities monitor environmental conditions and adjust and respond.

Lora is a perfect technology for sensors, as batteries can last for years, and it is long range.

An example application of LoraWAN as part of a Smart City ecosystem is its use in Smart Parking systems.

Smart parking systems use sensors embedded into the floor of a car park, to detect whether there is a car in a parking space.

This data is used to direct motorists to available free parking, and to make cities run smoother.

Yesway is based in Lincoln, UK.

+44 (01522) 740818

This article was written by Yesway engineer Craig Miles

Internet of Things | Two Way Radio Wireless Communications – Yesway Communications

LoraWAN Marine Smart Generator

Smart Generator – This article explains how a marine generator works, and how it could be improved by adding LoraWAN IOT (Internet Of Things) as a smart ships generator.

The first part of this blog post explains how a marine ships generator works, and how to service and test it.

The article will also look at ways that traditional ships generators can be converted into a smart ships generator, by adding LoraWAN IOT connectivity.

How a Marine Generator Work

How a marine generator works is something I taught to students at South Shields Marine School many times.

The photo is of a marine generator from an old ship.

marine ships generator

The end has been removed to allow easy access, and for demonstration and test purposes.

The marine generator in the photo was original attached to the ‘Prime Mover’ (ships engine) by a coupling at the other side of the generator.

The coupling is connected to a shaft which goes into the generator casing.

Inside the generator casing the shaft is connected to a Rotor.

Attached to the Rotor are electromagnetic Poles.

The Poles are supplied with DC (Direct Current) electricity, and act as electro-magnets.

Theory states that electricity can be generated by moving a magnet through a coil of wire.

This is why the Poles attached to the rotor, are turned into electro magnets.

As the rotor, and hence the poles rotate, they are surrounded by large coils of wire.

The large coils of wire that surround the poles is called the Stator.

The Stator coil in a marine generator, consists of three sets of copper wire coils.

There are three sets because the generator is a three-phase generator.

The three coils are connected in a star configuration as shown on the screen.

Each of the phase connections, which I have labelled ‘phase 1’, ‘phase 2’, ‘phase 3’, are connected to the generator ‘Bus Bar’.

The Bus Bar is the output connection from the generator, which connects to the ships electrical system.

Generator Exciter

I mentioned earlier that the poles which are attached to the generators rotor, are supplied with DC (Direct Current).

The device that generates the DC voltage is called an Exciter.

The Exciter is attached to the same rotating shaft as the main generator (which is driven by the Prime Mover).

The difference with the Exciter compared with the main generator, is that the poles are fixed & do not rotate with the rotor.

Instead the rotor, which contains coils of wire, rotates between the poles.

Therefore like the main generator, the exciter produces electricity.

The poles in the Exciter differ slightly from those in the generator.

The difference is that they retain magnetism, even when the generator is not being used.

Without this residual magnetism, the generator would not be able to start.

This is because there would be no magnetic field for the coil of wire (in the stator) to move through.

Therefore no electricity generated.

Just like the main generator, the Exciter produces AC, or Alternating Current.

Therefore to produce the DC needed to supply the generator poles, the AC needs to be connected to DC.

This is done using a rectifier circuit, which is incorporated into the Exciter.

A rectifier circuit uses diodes to chop off half of the alternating current, so that only DC is produced at the rectifier circuits output.

This DC is then fed via wires, into the Poles of the main generator, creating magnetism in the Poles.

If we didn’t change the original AC produced by the Exciter, into DC, then there would not be a stable magnetic field produced in the generator Poles.

Fault Finding

If the generator has been idle for a period of time, and you try to start it, it may not work.

This is due to the loss of magnetism in the Exciter Poles.

The Poles are designed to maintain a residual magnetism, even when the generator is off.

This magnetism can however ‘leak away’.

This happens over a period of time, due to the fact that the Exciter is encased in a metal casing, which can absorb the magnetism.

If the generator will not start, and it has not been used for a while, this could be the generator starting problem.

The solution is to put the lost magnetism, back into the Exciter Poles.

This is done by what is known as ‘field flashing’.

You can field flash the Exciter Poles by attaching a battery to the Poles wiring connections, for a short period of time.

This will re-magnetise the Poles, and hopefully allow the generator to start.

Generator Maintenance Testing

A marine generator is both mechanical & electrical.

Mechanical Checks

Include bearing lubrication, and wear measurements, using Feeler Guages.

Electrical checks are mainly focused on the continuity & Insulation resistance values of the generator Stator.

Continuity Checks

As previously stated the three coil windings in a marine generator Stator are connected at one end, to form a Star connection.

Continuity checks test that the coils are not broken, and have a low electrical resistance, from one end of the coil to the other end.

The only slight problem you may face is that the ‘Star Point’, which is the point at which the three coils are connected together, is not accessible, on your generator.

This is because the Star Point is often buried in the Stator windings.

If this is the case,  what you need to do is measure the continuity through two sets of windings at a time.

This is done via the three Bus Bars, using a low range Ohmmeter.

The resistance should be low, and very similar, between the different coil combinations tested.

Insulation Resistance Checks

The three separate coils of wire in the three-phase generator Stator should have a high resistance between them.

If there was no or little resistance between the coils, then a short circuit would occur, and the generator would not run.

An insulation resistance meter tests the windings resistance  under realistic working conditions, by supplying a high voltage to the coils.

For a 440 Volt marine generator, you would normally set the insulation meter to double its normal operating voltage.

Insulation testers typically offer 250, 500 & 1000 Volts ranges.

Therefore for a 440 Volt marine generator you would test at 1000 Volts.

If you are regularly testing, you may wish to reduce the meter setting to 500 Volts, so not to unduly put stress on the Stator winding’s.

The minimum insulation resistance figure under SOLAS regulations is 0.5 Mega Ohms.

Though really you would not want to see anything below 2 Mega Ohms in a healthy marine generator Stator.

Smart Ships Generator

So hopefully now you understand how a traditional ships generator works, and its now time to consider how we can improve it.

…this article will be continued shortly….

We can help you integrate LoraWAN and other LPWAN wireless connectivity into your existing marine and factory generators.

We can offer onsite bespoke electrical engineering training & at your site, or at ours.

Our trainer is Craig , who has lots of experience in training electrical maintenance employees and students.

Phone: (01522) 740818

what is lora

Things Network

LoraWAN IOT

Things Network Lincoln is a worldwide crowdfunded and community operated IOT

The network uses a narrowband radio technology called LoraWAN.

LoraWAN operates in the UK and EU on 868MHz frequency.

The 868MHz frequency is what is known as an ISM band.

ISM stands for Industrial, Scientific, Medical.

ISM bands are unlicensed bands, so can be used by anyone.

The first Wireless Gateway device was built by the Lincoln Things Network Community, using components sponsored and supplied by Yesway Communications.

Lincoln IOT Service

The Lincoln Public IOT service is now live, and can be used by local business and academia for education and research into new IOT connected products, that they may wish to develop.

Check out the local page for the Lincoln ‘Things Network’

http://thethingsnetwork.org/c/lincoln

or watch this video introduction:-

The Things Network from Soda Content on Vimeo.

Its a brilliant idea, and I think that this will really help businesses and the general public develop products using the Internet of Things that will improve this world for the better.

For enquiries about the Lincoln Things Network, contact me via the page link above, rather than through Yesway, which is not connected with the network. I just happen to work for Yesway, and are also personally the Things Network initiator for Lincoln.

The two are separate, and I am only putting the details on the yesway site to spread publicity to our social media subscribers, so that more people know about this great free idea.

single phase as sine wave picture

Applying the Internet of Things (IOT) to Induction Motor Monitoring

Applying the Internet of Things (IOT) to Induction Motor Monitoring

Induction motors are found in all sorts of industries and applications, both on land and offshore.

Smaller Induction Motors (roughly drawing up to 10 Amps Full Load Current) most commonly use Direct Online Starting (D.O.L) methods.

Larger motors typically use starting methods such as Star-Delta starting, which keeps the starting current (surge / inrush) down.

The Internet of Things offers 24/7 monitoring of systems, which can intelligently react based on the input data provided by the networked sensors.

The main parameters of induction motors that could be measured are:-

Voltage (individual phase)

Current being drawn by motor.

Over current in individual phases, such as imbalances due to single phasing faults.

Phase Winding temperature based on measurement using thermistors.

Vibration Monitoring, indicating bearing failure.

Motor speed (inc comparison of actual to Synchronous field speed calculated speed).

What do we mean by the above parameters:-

Firstly lets consider the term, ‘Voltage (Individual Phase)’.

Voltage (individual phase)

The term ‘individual phase’ is applicable in three-phase supply systems.

Three-phase supplies are commonly used in industrial factories and workshops.

It is rare to have a three-phase supply in a domestic home.

To understand a three-phase supply, lets first consider a single-phase voltage supply.

In single-phase voltage systems (as found in most homes), an ac sine waveform ‘cycles’ above and below the centre zero volts level, at a frequency of 50 times a second.

This is known as 50 Hertz, or Hz, and is the supply frequency used in most, but not all, countries around the world.

single phase as sine wave picture

ac sine wave.

The picture above, shows a representation of an AC (Alternating Current) Sine Wave. The line through the middle would be zero volts, and as you can see the voltage rises and falls over time (time periods, starting at the left of the picture, and moving right).

For an AC voltage supply frequency of 50 Hz, 50 complete sine waves would be completed, per second.

Now that (hopefully) you understand what a sine wave is, you need to know that in a single-phase system, you have one sine wave, that goes up and down over time (as in above picture).

A three-phase voltage supply, has three sine waves at the same time. NOT ONE, BUT THREE!

Each of the three sine waves, is spaced 120 degrees apart, which means in plain English, that they rise and fall, at different times to each other.

For the purposes of Induction Motor Monitoring, you might want to monitor the phase wire, to check whether the voltage is on or off.

If the Induction Motor was a single-phase type, then obviously if the voltage supply was off, the motor would stop.

However, the single-phase motor may be tucked away from view, in a corner of the factory. Therefore being able to monitor the single individual phase supply, is still useful for an IOT induction motor monitoring system.

Being able to monitor all three voltage supply wires, to a three-phase induction motor, is even more useful.

If one of the three voltage supply wires, to the induction motor stopped supplying voltage, the motor would continue to run.

The motor would not run well on only two supply wires, but may go unnoticed, if in an out of the way location.

This is why using an IOT monitoring system, to detect the voltage of each of the three voltage supply wires, is useful.

Current being drawn by motor

Each Induction Motor will have a manufacturers specification for how much current is drawn, both at startup, and when fully running.

For more information on induction motor monitoring , get in touch.

(c) Craig Miles 2015-2020. All rights reserved. www.craigmiles.co.uk @acraigmiles

Internet of Things | Two Way Radio Wireless Communications – Yesway Communications