Radio dimming commands to streetlight

[Flyback]

Hello,
We need a RX/TX module in our streetlights. It should be able to receive the dimming signal from the radio wave.
Whatever it outputs we can add a micro to convert the signal to a DALI dimming signal.
The RX/TX module must not have electrolytic capacitors in it.
Do you know of one.?
Cheap as possible.

 

[rjenkinsgb]

What operating range?
Does it need to be a two-way data link?
What regulatory region are you in?

 

[alec_t]

Why does a street lamp need to transmit?

 

[Flyback]

Thanks, region is EU.
Yes , two way.
Transit needed for acknowledgement of dimming signal received.
Operating range is .......well, i assume the radio signal is sent over the mobile phone network... in UK

 

[JonSea]

A cell modem is quite different than an RX/TX module......

 

[rjenkinsgb]

well, i assume the radio signal is sent over the mobile phone network

That would mean every individual unit having a SIM card and active mobile service account... it seems totally impractical [and definitely not cheap].

DALI is intended for direct wired connection between addressable lamp controllers over a few hundred metres.
It seems a total contradiction to specify that then have a single-point access device at each lamp, with another unique address like mobile data??

There are already wireless DALI standards (or DALI2 anyway) using eg. Zigbee based mesh networks.
A system like that allows a single "connectable" controller that also has the lighting RF interface to manage tens or hundreds of individual lamps.

Edit - and another reference, dali plus rf:
https://www.mdpi.com/1424-8220/16/5/597/pdf

An existing add-on adapter:
**broken link removed**

 

[ronsimpson]

Zigbee based mesh networks.

From our experiments; It looks like a mesh network will go for miles and miles. If all lights can see another light you can jump and jump a signal across town. I think low power Zigbee will work in street lights. You might need high power on lights on the edge of town.

My problem is Zigbee = big money.

 

[rjenkinsgb]

Zigbee = big money

As an embedded module to build in to a product, they are a similar type of price range to a cellular radio module, eg.
https://www.mouser.co.uk/Embedded-Solutions/Wireless-RF-Modules/Zigbee-Modules-802154/_/N-6l7r4

I'm sure they can be found even cheaper if being purchased in bulk.

Edit - this looks to be a decent one, the low end of the price range, -40 to 125'C operating temperature range and available in EU or USA etc. versions.
https://www.mouser.co.uk/datasheet/2/268/atmel-42486-atsamr21b18-mz210pa_datasheet-1368786.pdf

It has spare I/O as well, so possibly the DALi code could be added and the thing pretty much directly connected to the ballast with just a simple level converter between them.

 

[unclejed613]

From our experiments; It looks like a mesh network will go for miles and miles. If all lights can see another light you can jump and jump a signal across town. I think low power Zigbee will work in street lights. You might need high power on lights on the edge of town.

My problem is Zigbee = big money.

you would also have to have the network locked down extremely well. you don't want somebody turning it into a botnet like this: https://www.forbes.com/sites/leemat...g-machines-and-light-bulbs-ddos-a-university/

 

[ronsimpson]

A very different thought: I know this does not fulfill the specifications but;
I have used FM broadcast radio to send commands to street lights. (red/yellow/green type)

FM (mono) transmits R+L=mono.
FM stereo radio transmits (R+L) & (R-L) to make R & L
There is also a optional third channel. Some times a forth channel.
I have used "SCA" to transmit more music or to control far away things.
A very low end FM radio with SCA should not increase the cost too much.

 

[audioguru]

All streetlights in my city have been converter to low power LED type. Each streetlight has a modem with its little antenna on top.
They never dim them. They turn on most of them at dusk and turn off most at dawn. Some of them stay turned on all the time and others never turn on.

 

[ronsimpson]

Some of them stay turned on all the time and others never turn on.

They have broken "modems".

Where I live there is lots of 10mhz radio signals on the power line. I need to look back at my log book but I thing most of the signals are in the 5 to 20mhz range. I told the power company and they said there is no such thing. I decoded the data and found voltage, current, phase data and some of what appears to be on/off commands with addresses. I told the power company what data I found and they said they have many 50w and 250w transmitters on the power line. They asked how I could see the data. lol

I don't know about your countries but here there is data on the power lines.

 

[unclejed613]

I told the power company and they said there is no such thing.

but of course.... they don't want "joe sixpack" messing around with their insecure infrastructure. "security by obscurity" never works. back in the days of hardware based radios, it did work some of the time, because it was difficult and expensive to ferret out frequencies, modulation methods and communication protocols. hardware had to be built that duplicated the functions in the target system, and lots of trial and error were required before usable data could be squeezed out of the signal. today with SDR all it takes is an inexpensive dongle, and software that is almost to the point where the whole process can be automated. as a matter of fact, i think Kali Linux comes with all of the tools pre-installed and the device drivers pre-compiled. you can run software that analyzes the modulation method, and picks out pieces of the communication protocol. "security by obscurity" is completely insecure and obsolete, and infrastructure that relies on it is an exploitation waiting to happen. if you look up the various computer security conferences on youtube, you can learn how these services are endangering themselves. for example, 115 batshit stupid things on the internet where people and infrastructure are visible on the internet, with little or no security at all, such as the controls of a steel mill, or the valves and systems of a hydroelectric plant, and they are actually the SCADA consoles and not just a read only image.

you might want to tell your electric company how you read the data because that is a system that is open and vulnerable. they need to fix it. they have a system that is open to tinkerers, pranksters or terrorists.

 

[ronsimpson]

you might want to tell your electric company how

I have a university friend that is one of the top power engineers and was the one that told me they will never admit to sending signals on the power line. I showed him the data and he confirmed it was his. He said that my transformer on the pole should not pass RF.

I was working in X-10 power line communication and built a scope probe just for this project. I wanted to see 50khz through 20mhz.

 

[johnnyuplink]

Hi Ron, if I make a top up on my smart meter is the purchase data sent via the National grid to my service provider??

 

[rjenkinsgb]

they will never admit to sending signals on the power line

If they admit it exists, they admit it is also insecure.
[I thought they started using powerline signalling with "Economy 7" meters switched via a signal from the substation, many years ago - or was that never implemented?]

A lot of big organisations still think "security by obscurity" is a clever approach...

There is an interesting talk on the subject here:

 

[Nigel Goodwin]

[I thought they started using powerline signalling with "Economy 7" meters switched via a signal from the substation, many years ago - or was that never implemented?]

As far as I'm aware Economy 7 works simply on a timer belonging to the customer, the meter itself provides different readings for different set times of day, and it's up to the customer to juggle their usage in the cheap periods. The customers own timer would be used for storage heaters etc.

I used to have HeatWise, these meters provided five different meter readings, and a switched output for storage heaters - the time wasn't fixed though like Economy 7, it could vary within certain limits - so you'd get something like 5 hours within an 8 hour window. The actual switching of the HeatWise output was done via radio signals, carried on one of the BBC radio stations (I can't remember which one now though?)