10M dollar L-Prize winning bulb from Philips, review and teardown

[Jarhead]

Nice teardown and review!

So I have a question..

So what good does the fusible link do for the consumer? So maybe there's a power surge for whatever reason. Blamo, the fusible link blows. What good is the fusible link? The light's still dead, the consumer can't replace it. It still has to get sent back to the factory for fix/replacement.

I'd rather have the link blow, than burn my house down. I once saw a CFL start smoking, then puffing, and it wasn't blowing the house breaker...

 

[adamantinepiggy]

I'd rather have the link blow, than burn my house down. I once saw a CFL start smoking, then puffing, and it wasn't blowing the house breaker...

I was thinking more along the lines of; why a fusible link instead of a easily replaceable cheap fuse or mini resettable circuit breaker or something?

 

[Jarhead]

I was thinking more along the lines of; why a fusible link instead of a easily replaceable cheap fuse or mini resettable circuit breaker or something?

Ah, I see now. At the prices, it makes sense, however they did test them, as well as abused the L-Prize bulb fairly throughly. Maybe a Polyfuse would make sense. Using a replaceable fuse might add too much cost.

I updated the review, added shots of the Home Depot "Consumer" Blister packaging, captured some data on the current drawn then created plots of those for anyone interested, and added a few other items.

 

[soccerballtux]

Questionable soldering practices is one of the largest culprits leading to product failure.

I regret posting this.

 

[LuxLuthor]

Ah, I see now. At the prices, it makes sense, however they did test them, as well as abused the L-Prize bulb fairly throughly. Maybe a Polyfuse would make sense. Using a replaceable fuse might add too much cost.

I updated the review, added shots of the Home Depot "Consumer" Blister packaging, captured some data on the current drawn then created plots of those for anyone interested, and added a few other items.

Newbie/Jarhead, saw a post from cy over at "you know where," about this great L-Prize Philips LED review you did. Great detailed presentation. It is the first practical LED fixture I would consider using, despite having a 30-40 year supply of various incands! Man, I miss reading your posts! Lost my previous Anandtech login, but joined again just to let you know how much work like this is appreciated!

 

[Mark R]

I was thinking more along the lines of; why a fusible link instead of a easily replaceable cheap fuse or mini resettable circuit breaker or something?

If something has happened that has caused the fusible link to fail, it usually means something catastrophic (like the driver transistor failing short-circuit) has happened. The lamp will likely be irreparable.

 

[wildkarde]

Exactly, if you had a transient through your house wiring strong enough to blow that fuse, your led bulbs being blown would be the least of your worries. That fuse is there to protect your lamp and the rest of your house from something blowing up inside the bulb, not the bulb form things outside.

 

[Rubycon]

If something has happened that has caused the fusible link to fail, it usually means something catastrophic (like the driver transistor failing short-circuit) has happened. The lamp will likely be irreparable.

Yes, a transistor is the fastest responding fuse known. 😉
Whether an anomaly causes it to go or it fails (shorts) the one shot protector opens to prevent a hazard.

Where a self resetting device makes more sense is a hair dryer, for example. If the inlet is blocked from it sitting on something and the airflow is restricted sufficiently to cause its heating elements to get dangerously hot, the device opens killing power. Some of these do use one shot devices (microtemp) rendering the appliance useless.

 

[Jarhead]

Yes, a transistor is the fastest responding fuse known. 😉
Whether an anomaly causes it to go or it fails (shorts) the one shot protector opens to prevent a hazard.

Where a self resetting device makes more sense is a hair dryer, for example. If the inlet is blocked from it sitting on something and the airflow is restricted sufficiently to cause its heating elements to get dangerously hot, the device opens killing power. Some of these do use one shot devices (microtemp) rendering the appliance useless.

I have seen transistor based "fuse" circuits turn to molten slag, and the transistor become a short itself, resulting in zero protection. I've seen the same for 2500W transorbs placed before the circuit, to protect the transistor "fuse" circuit, turn into shorts and opens themselves (transorbs go between the power and ground and clip/clamp the voltage on the line).

 

[Rubycon]

I have seen transistor based "fuse" circuits turn to molten slag, and the transistor become a short itself, resulting in zero protection. I've seen the same for 2500W transorbs placed before the circuit, to protect the transistor "fuse" circuit, turn into shorts and opens themselves (transorbs go between the power and ground and clip/clamp the voltage on the line).

Yes, catastrophic failure must always be handled with ancillary parts with appropriate interrupt capacity! 😉