Failing Megaman Dimmerable 11W CFL GU10s

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Hi Everyone:

I did a quick search of this site and have discovered several posts reporting trouble with Megaman Dimmerable CFL GU10 lights.

We have installed 14 of the warm 11W GU10s here in ceiling downlights. The bulbs came with the light fittings (Flameguard CF409s). There are three circuits: One with 6 lights and two with 4 lights each. The dimming switches we used were recommended on the Megaman site. We calculated the load on each dimming switch as described on the Megaman site and got the appropriately rated switch. They were always started at full power, allowed to warm up for a few minutes and then dimmed if required.

Since installation in the autumn of 2009, 13 of the lights have failed. Not dramatically, or anything, they just fail to come on one day. After about 4 of them failed, we took off the dimming switches and replaced them with normal on/off switches. That didn't seem to stop them failing. They were advertised as being good for 10,000hrs, but there is no way that limit has been reached.

We also installed a fourth circuit at the same time as the three dimmerable circuits. This circuit had three normal 11W CFL GU10s. So far they have worked fine.

Just wondering if anyone else has had a similar experience and if anyone can see if we have done anything wrong.

Cheers!
 
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It does sound a bit fishy that. Not used the dimmerable ones myself, but I have been using the normal megaman GU10 CFLs for several years without issue.

IMO for dimmable fluorescent downlights the way to go is PL lights such as these here.

The horizontal ones are the ones they use in banks, shops etc. The vertical ones are closer to the size of your standard halogen.

As standard most fittings come with a standard electronic ballast, but you can retrofit a dimmable ballast into most fittings - some may require a permenant live and a 0-10v dimming signal though.

This will certainly be more reliable than any all-in-one solution, though much more expensive.
 
I've had them for about 18months.
In that time I've had to replace 6 of the 10 that we have.

However, they are on quite a bit, I reckon 18months at maybe 7-8 hours a day is about 4000hours.

So yes, now you come to mention it, they did fail a bit prematurely....

I've still got the failed ones, maybe I should send them back!
 
Megaman lamps seem to have a really high failure rate. I stopped using them ages ago when it started to become a joke.
 
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Steve -

Thanks for the reply. Yeah, I can't see how we did anything wrong. We followed all the advice on the Megaman website, even down to using dimmer switches they recommended. I think the cheapest option I can try now is to go to Megaman about this and see if they will replace the bulbs with the normal CFLs. Those have been fine ... so far.

I've heard you can get dimming LEDs now that are GU10 fittings, much less fussy and actually produce usable light. They don't use much electricity and run a lot cooler than even the CFLs. Maybe I'll look into them.

At this point I don't think I can go down the route of the PL lights. Aside from the cost it'll take too much to refit all these lights. Thanks for your feed back, though. I'll look at PL lights for the next job.
 
Thanks toasty and aptsys! I went onto the Megaman website and sent them a message about this. Let's see what they say. I'd settle for replacing the failed dimmerable ones with normal GU10 CFLs. Where I have them in the house, they seem to be holding out. I'll post their response here.

Cheers!
 
If your fittings were supplied with CFLs, they might not be able to take standard halogen lamps.
 
RF Lighting -

I don't think they will take standard GU10s. The standard ones would fit too far up in the lamp. Plus there is the heat the standard ones generate.

What I'm thinking is that I will give up on this dimmerable technology and just go with straight forward, non-dimming CFLs. They are the same size as the dimmerable ones, so they'll fit properly.

I've written to Megaman about the problem. We'll see what they say and I'll post their response here.


ban-all-sheds -

It's a kitchen of about 25 square meters. The lights are set up to illuminate certain parts of the kitchen. Six of them are over an island, four are over a dining area and four are along the units where the fridge and oven are. You could have all of them on if you wanted - and it is pretty well lit then - but most of the time you just have one circuit or another on - like when the boss is at the island making dinner and she has the island lit up.



Thanks for your help, guys. Maybe these dimmerable CFLs were a bridge too far. Looks to me like the technology hasn't been worked out yet.
 
I use the Megaman Dimmerable CFLs in the SES base for wall lighting in a few rooms in my house. Apart from suffering from the usual CFL weaknesses (starting 1 second after turning the switch on, taking ages to produce any usable light output, and generally being 100 times poorer than the incandescent ones they replaced in everything but energy consumption) I had 1 fail out of 14 within a day of fitting. One other flashes like mad at anything below 50% dimmed. I am not impressed with them at all, however I never believed the cost savings in the first place. For me the choice to use them was cosmetic - I wanted a whiter more natural light in those areas.

I use some Phillips dimmable LED GU10 bulbs (x4, 5W or 7W I can't remember which) as the main lighting in my sitting room. The output is about 1/4 of the actual stated halogen replacement rating (again, no surprises there), but they have been working flawlessly for many months now. They are instant on, at full temperature immediately and can be dimmed down to almost nothing (i.e. fully on!) without flashing, etc. I initially fitted a standard Megaman GU10 CFL along side to compare and the output is about half the CFL.

I use LED lighting exclusively in my kitchen. I have 12 GU10 base LED bulbs in the ceiling (a mix of 4 wide spread for general lighting and 8 narrower spread aimed at the breakfast table, sink, door, etc) and 12x 2W G6 as under cabinet lighting. The result is good lighting everywhere, but I dread to think what the bulbs cost in total.

I did have 600W of lighting in my hallway (5x5x20W fittings) and I replaced 4 of the five 20W bulbs in each fitting with 9W Megaman CFLs with a G9 base (I couldn't replace all 5 in each fitting because of the delay in them turning on after switching). When the lamps are first turned on you can barely see anything for about a minute as the lamps warm up, but after that you risk getting skin cancer if you venture out under them. Why oh why can't they invent some decent CFL lighting that comes on quickly and at the desired temperature?

I have now learnt my lesson and will stick to halogen and, whilst still available, incandescent bulbs.
 
It's a kitchen of about 25 square meters. The lights are set up to illuminate certain parts of the kitchen. Six of them are over an island, four are over a dining area and four are along the units where the fridge and oven are. You could have all of them on if you wanted - and it is pretty well lit then - but most of the time you just have one circuit or another on - like when the boss is at the island making dinner and she has the island lit up.
Do you not see anything wrong with that?

i.e. that the format of lighting you have chosen, little 2" diameter recessed jobs, is useless at actually providing general room illumination?

66W of fluorescent lighting for an island? You could do it with about ⅓ of that with lighting designed to do the job you want it to do rather than lighting designed to do a completely different job.


Thanks for your help, guys. Maybe these dimmerable CFLs were a bridge too far. Looks to me like the technology hasn't been worked out yet.
Dimming CFLs is not a problem, provided you start with properly designed luminaires with properly dimmable HF control gear. Where the problem comes is with the replacement lamps with cheap and nasty electronics built into the base.
 
. Why oh why can't they invent some decent CFL lighting that comes on quickly and at the desired temperature?
They have done, and they use lamps such as these: http://www.lighting-direct.co.uk/Compact-Fluorescent/

The problems you have had all stem from trying to use inappropriate technology.


I have now learnt my lesson and will stick to halogen and, whilst still available, incandescent bulbs.
The lesson you should have learned, which ought to have been reinforced by the crazy wattage you were having to employ (600W for a hallway? :eek: ), is that the fundamental design of your luminaires is wrong. They are not fit for purpose, and fiddling with the type of lamps you put in them will not change that.
 
They have done, and they use lamps such as these: http://www.lighting-direct.co.uk/Compact-Fluorescent[/QUOTE]
I have one of those type in my bathroom (along with a few of your favourite MR16s above the mirror), and one in my utlity. Both still take a few moments to turn on, and take about a minute to reach full brightness. :?:

I was also unable to find any 2 or 4 pin CFLs that are dimmable? I would have prefered them to the SES Megaman Dimmerables I have in the lounge wall lights.

The lesson you should have learned, which ought to have been reinforced by the crazy wattage you were having to employ (600W for a hallway? :eek: ), is that the fundamental design of your luminaires is wrong. They are not fit for purpose, and fiddling with the type of lamps you put in them will not change that.
The hallway is around 28 metres long, in a Z shape, with natural light only at either end so once you get about 2m down it is dark without lighting in the daytime. Previously there were 8 100W pendants lighting it, so I replaced it with 5x120W fittings with 20W halogen capsules which lit it fine (I tried using 60W bulbs in the pendants but it was too dark outside the bedrooms). There is a reason why I've had to choose fittings with a < 100mm base btw - there are roses in the plaster that I don't want to damage or remove. The 3 fittings I removed were replaced with round white junction boxes which are hardly noticable unless you knew they weren't part of the plaster.

The LEDs in the kitchen work perfectly for the style of the room - all the work surfaces are lit with just 24W, and the 44W in the ceiling lights the room as well as the large FL fitting it replaced, whilst allowing the light around the corner by the door (which was previously a dim spot). BTW the spots are on bars, not in the ceiling propper, and are directed at the areas to be lit and not the floor. The added advantage is no heat is generated whatsoever - when working under the FL tube for a few hours I would notice the heat.
 
Both still take a few moments to turn on, and take about a minute to reach full brightness. :?:
HF control gear.


I was also unable to find any 2 or 4 pin CFLs that are dimmable? I would have prefered them to the SES Megaman Dimmerables I have in the lounge wall lights.
dimmable HF control gear.
It's what you plug those lamps into that determines whether they can be dimmed or not, not the lamps themselves.


The hallway is around 28 metres long, in a Z shape, with natural light only at either end so once you get about 2m down it is dark without lighting in the daytime.
Ah - OK - I must admit I was thinking of a more normal hallway...

Have you thought about cold cathode lighting above a cornice?

 

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