Re-sync when kitchen lights turned on

Our kitchen has had a mix of LED and Halogen lights for a couple of years now. Recently, whenever the kitchen lights are turned on, the internet connection speed adjusts. We are on a line with an attenuation of 59 or 60dB and the speed jumps around in the range between about 2600 and 3000 Kbps. It doesn't seem to be re-connecting when it adjusts the speed as I am on a dynamic external IP and that remains the same after the speed adjustment. I've tried with 2 different routers and power supplies but the effect is the same.

Anyone any idea what may be causing this. I suspect that it may be the electronics in one of the LED bulbs starting to get tired but that is only guesswork.

what you need to do is remove all of the lights, then put them in one by one to find the one with a problem. If you happen to have starter check that as well.

If this happens with just 1 light (try another as 1 light) then it may be the switch that's faulty.

iand

Thanks for the help. As a starter for 10, I swapped all of the LEDs for halogens and the problem stopped. Just a case now of deciding whether to stop with LEDs and identify the faulty one or staying with the halogens.

While I would prefer to stay with the LEDs (because they cost a (comparative) fortune and I haven't had full use of them yet and because they help keep the energy bill down) I don't know whether I can face the hassle of taking them out and replacing them one by one again when the next one starts to fail.

Best bet is to use a technique of halving.

Rather than doing it 1 at a time take half of them out. If the problem stops you know that half are fine. If it continues then take out half again. Each time you see if there is a problem in the half you have in or the half you have out.

This way you can find a single failure quickly. The issue is if you have multiple failures but done right this technique will still work.

ian72

Thanks for the tip. For the moment I've got a full set of halogens in and the broadband connection has been rock-solid for 24 hours. If I do put the LEDs back, I'll certainly use that technique. However, I am wary of the LEDs now as I am making the cautious assumption that if I find the one that has started to fail (even thought the light output seems to be the same as normal) then the next one to fail won't be far away and I've got to go through the whole performance again.

As long as you have bought reputable LEDs they/(or their built-in drivers) should fail very rarely. I've had a few go in one particular fitting, but that blew the plug fuse each time. It sounds like one of the drivers to me.

Clearly not reputable as I've found 2 out of 9 that are putting interference into the system!

What you have found is "perfectly usual" and almost normal.

Inside an LED lamp will be a small switching circuit (basic SMPS) that converts the incoming 230v 50Hz to a very low voltage, DC, current source to drive the individual LEDs which may be in series, parallel or a combination. The circuit can run at anywhere from 10Khz right up to 500kHz or potentially 1MHz.

The leakage of noise from the lamp cannot be easily avoided - it will be both radiated and conducted. Because of the production process and desire to keep costs down very little consideration is given to shielding and repeatability - so two lamps produced in sequence may run at a different frequencies and may have varying amounts of shielding.

Some points to consider - where does the phone line run in relation to the lighting circuits? Not just the problem one but all of them? And remember the drops to switches. To close and you will have an issue. If they cross they should do so at 90 degrees to minimise noise pick up, if they run parallel for any distance another opportunity for noise.

So, look at where the phone line runs and consider putting the modem as close as possible to where it enters the house.

Secondly, fitting ferrite cores/beads to the individual lamp feeds may help reduce the conducted noise levels - you may will almost certainly need an electrician to do it and he will need to ensure they do not get hot

Another thought:

Are the lamp fittings actually suitable for LEDs? The switching circuit has power losses which turn into HEAT and that has to be dissipated somewhere. If you have close fitting fire rated fittings there may not be enough air flow to cool the electronics which can cause early life failures. Halogens are designed to radiate the heat forwards and whereas they get hot, there is nothing to fail.

M H C

Thanks for both posts. The incoming telephone circuit comes from an NTE5 box at the top of a back bedroom by a BT fitted extension through the house to a wall fitting in the downstairs front living room then a soap-on-a-rope filter to the only landline connected phone and couple of metres of cable to the router. The lighting circuit for downstairs comes from the Circuit Breaker box by the front door so the two wires nearly certainly come into proximity somewhere. The LEDs are/were in ventilated fittings suspended from 240v tracks.

It will be difficult to shift any of the kit around to move the router up to the where the phone circuit enters the house and will probably cause different problems as we live in an 1870s house that has been extended at the back by building onto the 18-inch thick stone wall that was the original boundary. Putting the router by the NTE5 would then mean some sort of technology to propagate the wireless signal on the front side of the wall.

If anybody is still reading and hasn't yet lost the will to live, would it make sense to run a shielded RJ11 phone cable from a filtered faceplate on the NTE5 to the router if I do have to start tinkering with the infrastructure?

A shielded cable might help but a better solution would be to get a separate Modem and Router or to supplement the existing Hub with a small switch and Wireless Access point.

Rather than run a shielded RJ11 (actually shielded 2 pair Cat5e with RJ11 connectors), run a full Cat5e cable between the two locations. Install a standard back box at each end and fit RJ45 sockets. Ethernet signals are a lot less prone to noise than the basic DSL signal.

Then EITHER.

Install a modem at the point of entry and the Ethernet output from the modem connects to the RJ45 socket with a short patch lead. At the other end another patch lead connects the RJ45 to the router.

OR

Install your existing hub at the point of entry - you will have wireless there and several Ethernet ports. Connect one of those ports to the RJ45 socket and at the remote end, connect the RJ45 to a small 4 or 8 port switch and the WAP to the switch.