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Standard User PhilipD
(experienced) Wed 03-Jan-18 08:08:49
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Re: LED streetlights - any experience


[re: MHC] [link to this post]
 
Hi

Put it this way, the power supplies used are a switch mode power supply, and I expect the LED lamp will have a better designed power supply than the ones gathered around your modem, including the very one used to feed power directly into to your modem/router.

The LED lights themselves are in a metal housing for heat dissipation, this also provides very good screening.

It's unlikely you will see any problems with electrical noise, and they may even be an improvement over the sodium designs these replace.

Regards

Phil
Standard User kitcat
(experienced) Wed 03-Jan-18 12:08:22
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Re: LED streetlights - any experience


[re: PhilipD] [link to this post]
 
PhilipD

LED lights do not need heat dissipation the metal is for protection from the environment. LEDs are cold to the touch and such low wattage that they do not heat up the surrounding glass much at all.
Standard User MHC
(sensei) Wed 03-Jan-18 13:19:42
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Re: LED streetlights - any experience


[re: kitcat] [link to this post]
 
It is not the LEDs but the power supply that needs the heatsink and that is also the potential noise source.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit


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Standard User danielmec
(newbie) Wed 03-Jan-18 14:29:01
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Re: LED streetlights - any experience


[re: MHC] [link to this post]
 
The LED lights heads will have needed to be CE marked, which for this class of product in includes compliance with the Electromagnetic Compatibility Directive (EMC) 2014/30/EU.

This link has a nice diagram of a few of the standards that feed into the process for this class of device:

https://www.sunpower-uk.com/support/power-supply-saf...

If really concerned, the OP could just submit an FOI request through WhatDoTheyKnow.com for the CE mark details and Declaration of Conformity paperwork to the Council.

Star gazing friends note that LED lighting causes them more of a problem, as they can't just put a notch filter around the frequency of sodium emissions.
Standard User ukhardy07
(knowledge is power) Wed 03-Jan-18 16:28:21
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Re: LED streetlights - any experience


[re: MHC] [link to this post]
 
You would have freaked out in my old place... I think this kind of setup is so common in London in these flats.

We had a front entrance, and on the right hand side a cupboard with everyones electricity meters, some of which were smart meters.

Next to the electricity meters were also the master sockets stacked next to one another for each flat, then extension wiring fed upto the flats, running side by side to the mains electrical wiring + doorbell wiring for each flat. The BT drop cable came from underground next to all of the electrical wiring, so it seemed even outside the flats these things were mixed underground (although possibly not).

In the flats BT has often installed second master sockets.

It had clearly caused problems as some flats (mine included) had the masters in the cupboard cut out, and the wiring in the walls bypassed. My flat had the original master in the cupboard cut out, and then jelly crimps connecting a new cable, which came out from the cupboard, and then ran along the skirting board, and up 4 floors, following the way you walk - rather than using the cabling built in the walls where the electricals run. Another neighbour also shared my cable, there was a BT junction box mid-way, with 2 cables coming out, 1 for me, 1 for them.

When I had an engineer out he tested my original cable, as it was still there, and stated it didn't pass the noise tests. Interestingly most of the flats were still using that setup.

I went to a neighbours, bearing in mind we were 3 buildings down from the exchange and their TalkTalk ADSL2+ was synced at 3Mbps, they had it plugged into their second master lol. I don't remember the exact NM, but it was around 20db, so it seemed banded. Some of the buildings were EO, others were not, my property had 3 addresses on the BT checker, 1 of which showed fibre so I ordered that and it worked out. My flat had 3 masters dotted around, but only 1 connected and worked.

Honestly you see so many in London with syncs as low as 2Mbps. I go to friends all the time and cannot believe the sync. Probably the worst I've seen is in Canary Wharf they had 0.8Mbps and had apparently had BT out and that was all they could get, due to line length. They also had something called Relish, basically 4G unlimited wireless broadband, but that was equally poor. They were in the TEST socket.

I've also seen plenty of new build with glossy master phone sockets, with built in TV ports. Again the syncs usually poor.

Edited by ukhardy07 (Wed 03-Jan-18 16:33:07)

Standard User MHC
(sensei) Wed 03-Jan-18 16:47:31
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Re: LED streetlights - any experience


[re: ukhardy07] [link to this post]
 
I've done enough tidying up of wiring in my time along with managing installing and reworks.

EMI/EMC/EMS/RFI ... are problems I have seen for too many years though bad design, failure to test appropriately, bad manufacture, cost cutting, bad layout, bad installation &c &c. A device can claim CE compliance - but use of te mark is not policed and it is only when challenged anything is done - a standard comment is that CE stands for "Chinese Export".

How about a power supply where the switching transistors were mounted on the heating which formed part of the outer case - wonderful, except it would act as a great radiator. With a street light it is possible there could be EMI at a level which meets spec especially as it is normally intended to be 5m away from other devices but put a cable close by and there is pick up.

Having done some more digging on this the Jury is out - and I will just have to wait and see.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit
Standard User MatHal
(newbie) Wed 03-Jan-18 19:05:15
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Re: LED streetlights - any experience


[re: MHC] [link to this post]
 
There are TWO CE marks, one of which may well mean China Export and is an inexact copy of the proper one. Many Chinese manufacturers use this second mark and those products may, or may not, pass CE certification.

The issue of interference is related to the switch-mode power supplies used for the LEDs. I've investigated quite a few domestic lamps and found variation in the design of these supplies. However, I've also found lamps that simply connect the LEDs in series across the supply with a dropper capacitor. That type would not cause interference but it is very unlikely the council would employ such a unit as one LED failure would put the lamp out of action - something that's not the case where the LEDs are driven by a power supply.
Switch-mode supplies DO produce radio interference, which can easily be demonstrated by bringing a medium-wave radio close to one and scanning the band. ADSL uses multiple carrier frequencies in the long and medium wave radio bands. Any carriers that are severely affected by interference are not used.
Interference is reduced by the twin-wire design of the wiring back to the exchange, much of which is twisted-pair. It is the excellent design of this wiring that has made it possible to put DSL signals onto phone circuits that were originally designed only for low-frequency audio signals. The drop wire is not normally a twisted pair but a simple twin; it should still be fairly immune to interference, however, as the wavelengths of the radio frequencies used are much much larger than the gap between the conductors. Any pick-up should therefore affect both wires in the pair identically and balance out.
Where there is a poor connection of one wire in a pair there will be an unbalanced situation which will certainly cause RF interference to be picked up so if you do have an issue it would be a good idea to get your connection checked.
Standard User MC31
(member) Wed 03-Jan-18 22:13:17
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Re: LED streetlights - any experience


[re: ukhardy07] [link to this post]
 
That wiring has 100% been put in wrong . A lot guys and so called managers got the "3 Metre rule " plain wrong.IE you should not have NTEs in the ground floor meter room. And 2 master sockets on the same line !

these comments are my own and in no way represent any company that i may or may not be linked too.
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