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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

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    • CommentAuthorRex
    • CommentTimeJan 28th 2020
    What ho one and all,

    Getting my knickers in a twist. Have some external lights that are not really sufficiently bright so am considering changing the current SES / 10W CLF for something LED.

    I do not know the lumen count of the CLF and 10W does not seem to really illuminate much space in front of the garage. But in old terms, what was the wattage of a 10w CLF?

    LED lights sometimes do have the Lumen output and a wattage, but they frequently say (for example) 5W LED = 50W. But my current 10W CLF is double a 5W LED but there is no way it is likely to be as bright.

    So in terms of LED wattage, presumably, I am seeking the biggest number with the most Lumens and that will not relate to any of the CLF numbers?
    Others are no doubt more experienced at this than me but I think what you're after is the Luminous Efficacy, which is essentially the 'lumens per watt' of a bulb.

    This guide has a table with some targets to look for and relates it to the old fluorescent tubes, halogen bulbs etc.

    • CommentTimeJan 28th 2020 edited
    Wot DT said.

    If your 10 W CFL lamp is anything like this https://www.cromptonlamps.com/AdditionalDepartments/Footer-Content/Discontinued/Discontinued-CFL/CFL-T2-Mini-Spiral-10W-2700K-SES-E14-BPCFMSP10WWSES-1BL then it may have an output of about 650 lumens.

    I just happen to be looking at an 10 W LED floodlight and that has an output of 680 lumen, so not much difference. There are 20 W and 30 W similar models though, and not quite the same 50 W ones (4000 lumen). https://cpc.farnell.com/minisun/20340/floodlight-50w-pir-6000k-led/dp/LA07108 (edit: note that all these floodlights are built as a unit though, so you have to replace the whole thing when it dies.)

    I suspect you may have trouble finding anything more than 8 W LED lamps with an SES base (800 lumen); at least I was just unable to find any. Ditto for CFLs with an SES base. There don't seem to be any nowadays. So you may have to consider changing the fitting if you want much more light.
    The previous owner of our place has installed 4 PIR floodlights with integrated LEDs, from the own-brand range of a major national retailer. They have all failed so will need replacing, think the PSUs have gone. Don't know how old they are but one is mounted on an extension that was built three years ago, and they are still stocked by said retailer.

    Technically, replacing a floodlight unit is outdoors wiring, so should be done by an electrician, which is way more expensive than just replacing a bulb.

    I will be steering well clear of led-integrated floodlights in future and looking for replaceable bulbs.

    Edit: would this fit in the space?
    How old is the CFL ? they can suffer quite a lot from degrading performance over time. It might be worth swapping the CFL for a (spare or borrowed) led bulb if you have one to gauge the performance of the CFL
    • CommentTimeJan 29th 2020 edited
    Posted By: WillInAberdeenTechnically, replacing a floodlight unit is outdoors wiring, so should be done by an electrician

    Obviously any electrical work needs to be done by somebody who knows what they are doing, but I don't believe there's any requirements above that for outdoor work. In England at least; I believe there still may be in Wales. Don't know about Scotland or NI. One for one replacement is permitted even in special locations for that matter.

    I will be steering well clear of led-integrated floodlights in future and looking for replaceable bulbs.

    I wholeheartedly agree with the concept but it's getting more difficult to do for floodlights. I've only had one failure so far and that was of the PIR unit, so I was able to wire a new separate one in parallel.

    What IP rating do the failed units have? You could try arguing they're not fit for purpose, since they've all failed. Up to you to prove it though, I think.
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