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0 pointsJohnFen3y ago0 comments

Low voltage DC lighting is a thing that has existed for a very, very long time. That most houses don't have it is more cultural than anything else, in my opinion.

That means it's totally fixable. You can install such a system in existing buildings right now, and it's not crazy expensive unless you want to run the wires inside the walls.

If we could shift cultural expectations around this, adding a LV system in new construction would not significantly increase the construction costs. It will start to be done if buyers start demanding it.

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xxs3y ago

12V requires quite a lot of amps for enough light, so low DC is not optimal. Also LEDs are current driven devices, i.e. they will be sensitive to voltage changes (even with a current limiting resistor)

JohnFenOP3y ago

Low-voltage doesn't necessarily mean 12V. I think it's anything below about 50, although lighting systems currently marketed as "low voltage" are usually 12 or 24 volts.

The constant current thing is true, but that's not a terribly difficult problem.

Dylan168073y ago

It's complicated. https://en.wikipedia.org/wiki/Low_voltage

Depending on who you ask, the limit for low voltage DC might be 42 or 50 or maybe 60 or 120 or 1500.

yencabulator3y ago

For example: the stairwell shin-height lights in this 90s house are 12 VDC. There's a transformer plugged into a wall outlet in the nearby storage closet.

midoridensha3y ago

That works OK because the transformer is relatively close to the lights. If it were a reasonably-large house, and the transformer were on the opposite side of the house, you'd have a problem with a noticeable voltage drop. All these ideas people are throwing out here involve a single whole-house power supply. If it were for 48VDC, it would probably be fine, but 12V would result in significant line losses.

yencabulator3y ago

We already see transformers for a run of e.g. track lights, low voltage lights on tension wires, and so on. That's been a thing ever since halogens came to market.

Having multiple transformers is perfectly doable and commercially viable -- though I would appreciate more product availability for something easy to stash in the hollow space of a ceiling, like recessed lighting is installed.

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xxs3y ago

JohnFenOP3y ago

Low-voltage doesn't necessarily mean 12V. I think it's anything below about 50, although lighting systems currently marketed as "low voltage" are usually 12 or 24 volts.

The constant current thing is true, but that's not a terribly difficult problem.

Dylan168073y ago

It's complicated. https://en.wikipedia.org/wiki/Low_voltage

Depending on who you ask, the limit for low voltage DC might be 42 or 50 or maybe 60 or 120 or 1500.

yencabulator3y ago

For example: the stairwell shin-height lights in this 90s house are 12 VDC. There's a transformer plugged into a wall outlet in the nearby storage closet.

midoridensha3y ago

yencabulator3y ago

We already see transformers for a run of e.g. track lights, low voltage lights on tension wires, and so on. That's been a thing ever since halogens came to market.

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j / k navigate · click thread line to collapse