Smallest possible cable for a 4w LED load.

Energetic

Energetic

-
Hi All, This is a bit niche but i've been asked to refurb an antique lamp to dimmable led and i'm after a very tiny cable that will take 230v but only run a single 4W LED. There are 5 of these on the lamp that come back to a connector then off in 0.75 flex.

Also after an inline dimmer for the whole thing....

o_O

Thanks
 
Are you sure the LED is dimmable?
4W at 230V is less than 0.02 A so its not the current that will be the issue. But you need to ensure its insulation is safe for 230V and its robust enough for the intend use.
 
Hi - just been thinking about thin cables, ADS and the 6A MCB. There will be a limit to how thin the conductor can be for ADS to work without damage to the wiring if a fault occurred. From the Wylex data sheet to hand (for the let thru I2t) and the adiabatic eqn (k=143 from Table 54.2) then a 0.5mm copper conductor looks ok for PSSC of up to 2.5KA which would cover most situations. Otherwise we might need the dreaded 3A fan fuse :)
 
From the OP's reference to an inline dimmer I infer this is a portable appliance - please can you confirm? In this case, you might be in hot water with 0.5mm² internally and 0.75 to the plug, as the ACOP suggests a 13A fuse would be acceptable for the flex, but the 0.5 would not be protected. Perhaps it would be permissible to attach a label stating that a 3A fuse is required? It wouldn't wash on a new appliance because it would not be permissible in EU.

You might hide a fuseholder inside where the junction is, but many inline dimmers have a fuse, so if this is permanently attached to the fitting this might well be sufficient to protect the smaller internal cables.
 
Thanks for the replies and apologies for the confusion caused by my poor description. Please see photo, it is a thing of rare and terrifying ugliness...

It currently has a round pin 2A plug so was planning to put it on a 2A fuse on a normal plug but with 5 x 4W LED it could go lower still. I will supply a box of fuses with it for avoidance of confustion should it blow. It's for a family friend with no electrical knowledge so i suspect she'd call me rather than try to change it anyway.

20161209_100829.jpg
 
Well I was interested because I can't see how you will provide it.
 
westward10 said:
Well I was interested because I can't see how you will provide it.
Click to expand...

Currently the flex comes through the base and is cable tied. it's a one off commission for a specific situation, it's solid metal and seriously heavy and will be out of the way of any traffic including the flex .
 
Cable tie is not appropriate one off job or not, the fitting is not designed for a trailing cord.
 
OK so like I said it's a bit niche the back story is that it's a free standing victorian candle lamp that been previously converted to electric.... so I'm told... it's been in the family years and they want to update it.

If anyone wants to tell me that it's not genuine victorian etc I'm not interested.

It will be going in a windowsill behind some furniture and away from fiddling. the likelihood is that it's probably only going to be used a handful of times per year. it will be plugged into a socket via a fused plug and will be 30mA rcd protected.
 
I know I am harping on here but I cannot see a method for doing that in a compliant manner whether it is used once, twice a year or whether an rcd is involved.
 
Small point but its 1a total load. And LED have high draw current. And why dont you just use the existing cable as a matter of interest?
 
Vortigern said:
Small point but its 1a total load. And LED have high draw current. And why dont you just use the existing cable as a matter of interest?
Click to expand...
Eh? Neglecting power factor, it's less than 0.02A per lamp. I guess the new wire (if required) will be partly on the outside of the fitting and accessible, so having the required insulation properties and robustness will be the defining factors.
 
Cheers guys, I have just kept the original wiring other than the main flex. I've replaced dodgy connectors with slightly less dodgy crimps. I devised a cable clamp on the incoming flex also. It's as safe as i can sensibly make it

I found an Inline dimmer with a min load of 11W so it should work to about half light. Really impressed with the 4W filament LED lamps, they don't even get hot to the touch but they are very bright and i think the dimmer will be appreciated...
 
Energetic said:
Cheers guys, I have just kept the original wiring other than the main flex. I've replaced dodgy connectors with slightly less dodgy crimps. I devised a cable clamp on the incoming flex also. It's as safe as i can sensibly make it

I found an Inline dimmer with a min load of 11W so it should work to about half light. Really impressed with the 4W filament LED lamps, they don't even get hot to the touch but they are very bright and i think the dimmer will be appreciated...
Click to expand...
How have you enclosed the crimps.
 
Probably a lot safer now than when it was first made. Candles were a major source of house fires. There you go a positive reply!
Energetic said:
I'd rather not thanks, you will just tell me that it's inadequate
Click to expand...
I believe you would have got an honest review of the work you have done. good or bad would depend on the way it was done.
Can't be worse than the original tape and chock blocks?

tape and choc blocks.png
 
Lets not get all bitchy now. It's the season of good will and kissing under the mistletoe.
 

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Green 2 Go Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses Heating 2 Go Electrician Workwear Supplier
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

YOUR Unread Posts

Daily, weekly or monthly email

Receive a daily, weekly, or monthly email containing a digest of new and recently updated threads.

Thread starter

Energetic

Energetic

-
Joined
Location
South West

Thread Information

Title
Smallest possible cable for a 4w LED load.
Prefix
N/A
Forum
Lighting Forum
Start date
Last reply date
Replies
30

Thread Tags

Tags Tags
attach cable inline led load might possible

Advert

Thread statistics

Created
Energetic,
Last reply from
EastAnglian,
Replies
30
Views
5,285

Advert

TrueNAS JBOD Storage Server

Tilers | UK Tiling Forum | Tilers Forums | Find a Tiler
UK Tiling Forum by Tilers Forums UK
Plumbers Forums | Plumbing Advice | Gas Forum
Outside Play
Back
Top