Replace 12V MR16+transformer with LED

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Chis

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#251351 20-Jun-2019 18:32

We have a large number of MR16s with their own transformers around the house. Some of the MR16s are dying and so are some of the transformers. One room would ideally be dimmable.

To replace with LEDs, is it best to rip out the transformers and get new 230V LEDs (and I guess new fittings), or stick with 12V versions (that might work with the existing fittings) and try to work with the transformers, replacing as needed?

Any reliable and good value source of LEDs when a large number are needed? Approx price?

zyo

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#2261599 20-Jun-2019 18:39

Saw some Philips 6 pack 220v LED fittings in Miter10 over the weekend.
I think they are around 15 to 20 a pop. IP rated too.

sqishy

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#2261613 20-Jun-2019 19:06

I got these 230V Arlec ones also there is a larger version with 7 leds, they come in white/chrome.

Had them for 5+ years no issues.

https://www.bunnings.co.nz/arlec-5w-brushed-chrome-led-gu10-downlight_p00285777

richms

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#2261619 20-Jun-2019 19:22

If you get replacements with multiple lenses like those arlecs, you get horrible shadows which are even worse when drunk/etc

Richard rich.ms

zyo

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#2261637 20-Jun-2019 19:45

Gu10 is only good for staircase lights.

colinuu

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#2261697 20-Jun-2019 21:49

I replaced some MR16's in the kitchen recently with 7W 12V LED's (by GE) bought from M10 Mega. About $14 each IIRC. They have a 60 deg beam angle and I'm quite happy with them.

Interestingly though, while the lighting industry is now routinely producing LED lights with > 100 lumen/watt, these were only 70 lm/w. But, the lighting effect is very similar to the 50W halogens that were replaced.

Chis

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#2271294 7-Jul-2019 12:46

I think I'm best to replace my 12V MR16s (with dimmers) with 230V GU10s (with their own internal dimmers).

If I get use 12V LEDs then I found that my transformers would need replacing. I guess they can't cope with the low current.

If I use GU10s then there's never a problem with incompatible transformers and it's cheaper than a 12V LED + new transformer.

So now I'm in the hunt for good price bulk GU10 LEDs.

Where abouts do the best deals appear? Is it at hardware stores on occasional good specials, or are there online sites with better deals usually?

zyo

513 posts

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#2271826 8-Jul-2019 13:31

Chis:

I think I'm best to replace my 12V MR16s (with dimmers) with 230V GU10s (with their own internal dimmers).

If I get use 12V LEDs then I found that my transformers would need replacing. I guess they can't cope with the low current.

If I use GU10s then there's never a problem with incompatible transformers and it's cheaper than a 12V LED + new transformer.

So now I'm in the hunt for good price bulk GU10 LEDs.

Where abouts do the best deals appear? Is it at hardware stores on occasional good specials, or are there online sites with better deals usually?

Also transformers get warm which in turn wastes a lot of energy and defeats the purpose of having LEDs.

Sharesies

Trade NZ and US shares and funds with Sharesies (affiliate link).

richms

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#2271925 8-Jul-2019 16:16

Also when running GU5.3 LEDs off a 12v power supply there is additioal losses in the lamp from its driver supply, whereas a 230v driver only has one set of losses and is usually more efficiant since its not doing things like resistive droppers to limit current etc like some retrofit lamps have in them.

Richard rich.ms

gregmcc

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#2271951 8-Jul-2019 17:31

Chis:

We have a large number of MR16s with their own transformers around the house. Some of the MR16s are dying and so are some of the transformers. One room would ideally be dimmable.

To replace with LEDs, is it best to rip out the transformers and get new 230V LEDs (and I guess new fittings), or stick with 12V versions (that might work with the existing fittings) and try to work with the transformers, replacing as needed?

Any reliable and good value source of LEDs when a large number are needed? Approx price?

here are some things to think about.

1) Depending on the type of transformer (some of the electronic ones) simply wont work as they require a minimum load which LED can't provide

2) Do you have dimmers on any of these lights, some LED's can't be dimmed

3) replacing the entire fitting may be the way to go, but finding a replacement fitting that covers the hole of the old fitting could be problematic

Chis

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#2271952 8-Jul-2019 17:36

Thanks for all the tips and advice.

New GU10 bulbs will fit into the MR16 light fitting. They just need a new lamp holder (and the removal of the transformer).

We do have a couple of rooms with dimmers and I've noticed that only special LEDs support this, which is fine.

Now it's just funding the big replacement!

richms

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#2272097 8-Jul-2019 22:29

You cant change the lamp holder on a GU5.3 fitting to a GU10 and still have a compliant lamp. The whole fitting needs to be changed to something with the appropriate terminal block attachment and cover etc.

Richard rich.ms