Looking around at various sources, it looks like IPx4 should be suitable for an enclosed garden - it seems most vendors consider a typical garden as being "sheltered" as the walls, trees etc provide protection from the worst of the winds.
Anyway, I've installed some festoon lighting using a festoon harness and LED bulbs from TLC. Both are IP44 rated.
It all looks very nice and SWMBO likes them - especially the fact that they look like "real, old fashioned light bulbs"
But, so far we've had about 8 lamp failures out of 52 installed - there's another short string I've had up for years where I've replaced the old 25W lamps with 2W LED ones.
On investigating, I found that a "failed" lamp I removed actually worked - briefly before the RCD tripped (it was in an earthed metal holder when I tested it). It showed low IR between pins and cap - the reason for which was obvious when I opened it up :
Everything was wet, particularly the disk of insulating sheet which was between the LED module and electronics PCB - plus there was a small amount of water in the bottom of the bulb case. After drying out, works fine.
When the next ones failed, I noticed that it wasn't always a total failure, the red one at the right here is still glowing dimly :
I have raised the issue with TLC. Their first response is that it (the harness) is not suitable for outdoor use like this as it's not sheltered from rain. When I replied that it's more a problem with the LED lamps which are described as "Direct replacement 25W coloured incandescent lamps", they've just offered to take them back and allow me to order 25W incandescents. I've just emailed back to say that I chose LED to avoid having over 1kW or lights going
I'm thinking that I've hit a gap between the IP ratings and practical usage. The lamps may well pass the IPx4 test which only requires splashing for 5 or 10 minutes. But in real use, they will breath due to changes in temperature and environmental pressure - and as there's no seal whatsoever between cap and "bulb", are bound to draw in moisture even if there's no rain. I did note that when I unplugged the bulbs, a tiny amount of water had been drawn up into the space inside the harness socket seal where it seals on the the neck of the bulb casing.
At the moment I'm thinking that I'll have to dry them out and try sealing the bulbs properly. I've had some "old fashioned" 25W incandescent bulbs out in all weathers for years - and having a sealed bulb they've not had this problem. But at 300W for 12 bulbs, or 1.3kW if I'd added the 40 bulb set with them, not something I want on for too long
As an aside, the bulbs are "non dimmable" but actually dim quite nicely on a variac. Come on at around 25V and then vary in brightness with voltage. I've been running the main set outside at 55V - dad made a 110V transformer for running tools from, and made it switchable between 110V and 55V - and they are just about right for our setting on that. Full brightness with 40 lamps is "a bit bright" really, though the neighbours love them.
Internally there's an inductor (I assume, it looks like one and is labelled RX on the board) and a capacitor to drop the voltage, then a bridge rectifier, smoothing cap (it's noticeable that they don't have 100Hz flicker like many LEDs*), and current limiting resistor to the LED strings.
* I've found that many LED bulbs have a very pronounced strobe effect when there's any motion. I assume that they just have a bridge rectifier and current limiting resistor - no smoothing cap.
Anyway, I've installed some festoon lighting using a festoon harness and LED bulbs from TLC. Both are IP44 rated.
It all looks very nice and SWMBO likes them - especially the fact that they look like "real, old fashioned light bulbs"
But, so far we've had about 8 lamp failures out of 52 installed - there's another short string I've had up for years where I've replaced the old 25W lamps with 2W LED ones.
On investigating, I found that a "failed" lamp I removed actually worked - briefly before the RCD tripped (it was in an earthed metal holder when I tested it). It showed low IR between pins and cap - the reason for which was obvious when I opened it up :
Everything was wet, particularly the disk of insulating sheet which was between the LED module and electronics PCB - plus there was a small amount of water in the bottom of the bulb case. After drying out, works fine.
When the next ones failed, I noticed that it wasn't always a total failure, the red one at the right here is still glowing dimly :
I have raised the issue with TLC. Their first response is that it (the harness) is not suitable for outdoor use like this as it's not sheltered from rain. When I replied that it's more a problem with the LED lamps which are described as "Direct replacement 25W coloured incandescent lamps", they've just offered to take them back and allow me to order 25W incandescents. I've just emailed back to say that I chose LED to avoid having over 1kW or lights going
I'm thinking that I've hit a gap between the IP ratings and practical usage. The lamps may well pass the IPx4 test which only requires splashing for 5 or 10 minutes. But in real use, they will breath due to changes in temperature and environmental pressure - and as there's no seal whatsoever between cap and "bulb", are bound to draw in moisture even if there's no rain. I did note that when I unplugged the bulbs, a tiny amount of water had been drawn up into the space inside the harness socket seal where it seals on the the neck of the bulb casing.
At the moment I'm thinking that I'll have to dry them out and try sealing the bulbs properly. I've had some "old fashioned" 25W incandescent bulbs out in all weathers for years - and having a sealed bulb they've not had this problem. But at 300W for 12 bulbs, or 1.3kW if I'd added the 40 bulb set with them, not something I want on for too long
As an aside, the bulbs are "non dimmable" but actually dim quite nicely on a variac. Come on at around 25V and then vary in brightness with voltage. I've been running the main set outside at 55V - dad made a 110V transformer for running tools from, and made it switchable between 110V and 55V - and they are just about right for our setting on that. Full brightness with 40 lamps is "a bit bright" really, though the neighbours love them.
Internally there's an inductor (I assume, it looks like one and is labelled RX on the board) and a capacitor to drop the voltage, then a bridge rectifier, smoothing cap (it's noticeable that they don't have 100Hz flicker like many LEDs*), and current limiting resistor to the LED strings.
* I've found that many LED bulbs have a very pronounced strobe effect when there's any motion. I assume that they just have a bridge rectifier and current limiting resistor - no smoothing cap.
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