connectors for GU10 led replacement from 12v GU5.3 with transformer

[Neal]

I have had 6 50W 12v halogen GU5.3 downlighters in one room for years.

I am replacing them with LEDs. But I don't think the transformers I have will cope with the very low current draw from each LED.

So I am planning to replace them with 240v GU10s instead, bypassing the need for transformers.

I want to do this neatly and safely. I have new GU10 connectors, these have a simple 2 pole chocolate box on the end. I can directly remove the transformers, and wire these direct to the mains lighting cable in the ceiling.

But I want to do this neatly/safely. so I need to cover the choclate boxes. I could just use insulation tape, but that does not meet neatly/safely.

I am considering usings these 5A inline connectors:

They all emphasise 'flex' rather than cable. Is this an issue? Are they suitable/appropriate, or is there something more 'standard/recommended? I need them small enough to feed through the MR16 holes in the ceiling.

As an aside. Why do people use 12v downlighters (with the added expense of the transformers) when 230V appears to be fine?

Neal

[Neal]

I have had 6 50W 12v halogen GU5.3 downlighters in one room for years.

I am replacing them with LEDs. But I don't think the transformers I have will cope with the very low current draw from each LED.

So I am planning to replace them with 240v GU10s instead, bypassing the need for transformers.

I want to do this neatly and safely. I have new GU10 connectors, these have a simple 2 pole chocolate box on the end. I can directly remove the transformers, and wire these direct to the mains lighting cable in the ceiling.

But I want to do this neatly/safely. so I need to cover the choclate boxes. I could just use insulation tape, but that does not meet neatly/safely.

I am considering usings these 5A inline connectors:

edit. Cannot work out how to post an image link. No dropdowns for attachments/links etc visible... so plain text links:

original image at

They all emphasise 'flex' rather than cable. Is this an issue? Are they suitable/appropriate, or is there something more 'standard/recommended? I need them small enough to feed through the MR16 holes in the ceiling.

As an aside. Why do people use 12v downlighters (with the added expense of the transformers) when 230V appears to be fine?

Neal

[Johnny B Good]

====snip====

The 12v filaments are significantly more robust than their 240v counterparts and, for wattages in the range of 20 to 35 (possibly including 50 which I think is the absolute max for quartz halogen GU10 lamps), offer better luminous efficacy.

When we had our downstairs shower/toilet refurbished some 7 or 8 years ago, the wife insisted on replacing the single 60W bulb with a set of four recessed down lighters and I agreed only if 12v bulbs were fitted.

To this day, we are still on the original set of 35W halogens. However, rather than the electricians using classic step down transformers, to my surprise they'd actually fitted electronic "transformers" rated for a maximum of 60W at 12v (presumably to cater for the possibility of fitting

50W lamps).

These will current limit at just a tad over their 5A rating which significantly reduces the inrush current on switch on[1] (which is the major driver of filament lamp failure) further enhancing their longevity so I'm not altogether surprised at how long the lamps have lasted thus far. It's a triple 'whammy' of improvement, if you will, over the cheaper

240v lamp option since the electronic 'transformers' offer even more inrush current limiting protection than the old fashioned magnetic transformers ever could. [1] This current inrush protection is clearly evident in the short, 300ms or so, delay in ramping up to full brightness on switch on.

[Dave Plowman (News)]

That style of lamp first appeared only as low voltage. The mains version came later. I have both, and the low voltage ones produce slightly more light - and the bulbs last longer.

The low voltage type also allow a wider range of fittings because of the safe voltage.

I dunno if the 12v LED replacements are any better than the 240v ones in practice. LEDs don't need high volts to drive them, so its possible the internal bulb PS is easier with low volts. If so, would it be possible to re-group yours so one transformer feeds several - therefore above the minimum load?

[Neal]

Thanks to both Jonny and Dave - that makes sense

Dave- considered 1 transformer, but all the wiring is hidden above ceiling, along with junction boxes splitting the wires. Likely impossible to access the primary feed to insert a transformer there, given access is only through the lamp holes.

Neal

[Andrew]

Now that toberlone have increased the gap between the 'peaks', will choc blocks have to be re-designed too ?.

[Dave Plowman (News)]

Does that mean you already have more than one fitting per transformer?

I used those small electronic transformers that fit through the same ceiling hole as the fitting - to make repair easy, if needed. Some of those may work OK with LEDs - have you tried them?