RE: LEDs: What Types There are, How they’re Manufactured and How to Choose Which is Right for You

mcb1 — Sat, 10 Mar 2018 04:52:08 GMT

I have found consumer LED lighting notoriously unreliable. I don't get anything close to the 15 years

Sadly I think we'll be in this area for a while due to costs v customers expectations.

When I designed our house 16 years ago, LED lamps were just appearing, but were expensive and really didn't have a track record.

I used Dicrohic BUT used a decent brand and electronic transformers and this was in consultation with the supplier (whom also provided us with the lamps used on the Airport)

Because we were out in the country he also suggested RS (Rugged Service) lamps for the outside to better handle the vlotage fluctuations.

I did carefully design the lamp angle, placement and wattage. I don't think any of our electricians will do this as it's not in their interest to 'down sell' their services.

Over the years lighting in houses has got better and brighter, but sadly the move to flush mount fixtures (called downlights here), means the light is more focused and I've seen lounges that require 8 to provide a reasonably even illumination, which means that 600-800w is wasted on lighting.

I've seen many people put CFL lamps into these fixtures and sadly the illumination is even less as most of the light bounces around the inner portion of the fixture.

LED lighting will reduce that power bill, but the LED's themselves have a narrow beamwidth compared to an incandesent lamp, so you'll need more light sources.

Whenever you incease the component count, you're always going to increase the chance of failure.

Unless you are individually controlling each LED component within that lamp, you'll have some being overdriven resulting in early failure.

So even if the controller/driver for that lamp is correct, the internals may mean earlier failure can still be possible.

I have been involved in swapping incandesent lamps with LED for my friends widow.

The power consumption wasn't the major concern, it was the high ceiling meaning she was unable to change them.

The ones she chose weren't the cheap ones, they were Phillips and at $28 each we were both surprised that the illumination was greater than the 75w incandesents that we removed.

Unfortunately you can't dim these ones, so obviously they won't suit all applications, and I'm not sure many hours they have been running.

I've only replaced 1 lamp per year at $6 ea over the years, and with a lighting load of 250-300w total, the economics just aren't there.

Mark

RE: LEDs: What Types There are, How they’re Manufactured and How to Choose Which is Right for You

shabaz — Fri, 09 Mar 2018 18:23:05 GMT

Interestingly Avnet pioneered some interesting ways of working with manufacturers. They realized some time ago that the creators of fixtures/luminaires were not necessarily geared up to replacing incandescent with LED, so Avnet invested heavily in the ability to provide advice, light measurements, drivers, etc., to help those designers/manufacturers develop better products. Quite a novel idea, reaching out to help designers in such a deep way in this field.

It is covered in one of Bob Johnstone's books (he writes great books).

RE: LEDs: What Types There are, How they’re Manufactured and How to Choose Which is Right for You

genebren — Fri, 09 Mar 2018 17:49:38 GMT

Very interesting introduction to LEDs. I thoroughly enjoy working with LEDs. I have done several lighting projects using LEDs. Given how efficient and useful they are, I have had nothing but headaches with LED replacement bulbs that I have purchased. In the end, the issues lie more in the power supplies and less with the LEDs. Hopefully manufactures will build designs that will truly allow LEDs to shine in this application.

Gene