The LED can usually take it. The question is what the light does to the car. Almost every answer to this online is about whether the bulb will burn out. For a collection, the issue is the other way round: light damage to paint and printed card is cumulative, so a light that is on 24 hours a day delivers far more total exposure than one that comes on when someone is actually looking.
Hours matter more than brightness
Fading depends on the total dose of light - roughly intensity multiplied by time. That makes the switch-on pattern the biggest lever you have:
| Pattern | Hours lit per day | Relative dose |
|---|---|---|
| Always on | 24 | 12x |
| On in the evening | 6 | 3x |
| On when someone is in the room | 2 | 1x |
| On only when someone walks up | Minutes | A small fraction |
Same brightness, same LED: leaving it on around the clock multiplies the exposure twelve-fold against two hours a day. And the time it spends lit overnight in an empty room is exposure with no one there to see it.
UV-free is necessary, not sufficient
Choosing a UV-free LED removes the most damaging part of the spectrum, and it is the first thing to get right - CRI and Kelvin covers what else matters. But visible light still contributes to fading over long periods, especially on printed card and decals. UV-free plus fewer hours is the combination that actually protects a collection.
The practical concerns with always-on
- Heat in a closed case. LEDs run cool compared with old bulbs, but a sealed box traps what they do produce, and the driver or power supply is often the warmest part.
- Component life. Continuous running wears the driver and battery sooner than intermittent use.
- Battery-powered cases. Always-on and battery power do not mix; the light is only as useful as how often you have to recharge it.
What to do instead
- Put the light on a timer or a switch you actually use. Evening-only cuts the dose by three-quarters against always-on.
- Use motion or presence triggering where you can. The light is on exactly when someone is looking, and off the rest of the time.
- Keep the case out of daylight. A sunny window will do more damage in an afternoon than a UV-free LED does in weeks - protecting Hot Wheels from sunlight.
This is the reasoning behind how our Infinity Garage works: a UV-free-certified 4000K LED with 90+ CRI, switched on by a radar sensor with a 120-degree, 2 m range and switched off again after about 20 seconds. It is lit when someone walks up and dark the rest of the day. Full figures are on the specs page, and the trade-offs between trigger types are in motion sensor vs switch vs always-on.
FAQ
Can display case LED lights stay on all the time?
The LED itself usually can, but it is not ideal for what is inside. Light damage to paint and printed card is cumulative, so always-on lighting delivers around twelve times the exposure of two hours a day at the same brightness.
Do LED lights fade diecast cars?
UV-free LEDs remove the most damaging part of the spectrum, but visible light still contributes to fading over long periods, especially on printed card and decals. Fewer lit hours is what keeps the dose low.
Is it safe to leave a lit display case on overnight?
Generally, but a sealed case traps the heat the LED and its driver produce, and continuous running shortens component and battery life. There is also no benefit to lighting a car in an empty room.
What is the best way to switch display lighting?
Motion or presence triggering, so the light is on when someone is looking and off otherwise. A timer or an evening-only switch is the next best option.
Does a UV-free LED mean no fading at all?
No. It removes the worst of it, but visible light still adds up over time. UV-free lighting combined with fewer hours lit, and no direct sun, is what protects a collection.