CdS - contain Mercury ?

[Adum Chan]

I heard a new that product can't use CdS anymore because it contains mercury. RoHS will not accept this (lead & mercury). Is it true ?

If so, any mercury free CdS in the market ?

Rgds

 

[Nigel Goodwin]

I heard a new that product can't use CdS anymore because it contains mercury. RoHS will not accept this (lead & mercury). Is it true ?

If so, any mercury free CdS in the market ?

Rgds

CdS is Cadmium Sulphide, I wasn't aware the LDR's had mercury added?, it sounds unlikely? - is cadmium perhaps on some silly banned list?.

 

[audioguru]

Ni-Cads aren't made anymore because they contain toxic cadmium, so maybe that also applies to CdS. Use a photo-transistor instead.
The silly rules required users to dispose of them in a toxic waste facility. Nobody did so now they are banned.

Florescent light tubes contain mercury for their mercury-vapour UV glow inside but they aren't banned (yet).
What replaced the mercury in the "tilt switch" on the lids of my car? :?:

 

[Gorgon]

Ni-Cads aren't made anymore because they contain toxic cadmium, so maybe that also applies to CdS. Use a photo-transistor instead.
The silly rules required users to dispose of them in a toxic waste facility. Nobody did so now they are banned.

Florescent light tubes contain mercury for their mercury-vapour UV glow inside but they aren't banned (yet).
What replaced the mercury in the "tilt switch" on the lids of my car? :?:

Hi,
Cadmium is on the list. Ref: **broken link removed**

TOK

 

[windozeuser]

Ni-Cads aren't made anymore because they contain toxic cadmium, so maybe that also applies to CdS. Use a photo-transistor instead.
The silly rules required users to dispose of them in a toxic waste facility. Nobody did so now they are banned.

Florescent light tubes contain mercury for their mercury-vapour UV glow inside but they aren't banned (yet).
What replaced the mercury in the "tilt switch" on the lids of my car? :?:

Great :? I remember me and my friends when we were young; used to break old florescent tubes over trees. All that white dust flew all over us....

Do they still allow real mercury in thermostats mercury switches?

 

[zevon8]

Mecury is still used in tilt switches in thermostats. They slap a "contains mercury - dispose of properly" sticker on them. That and the price makes them as expensive as programable electronic ones, so the market is fading away. That combined with a limited market where they are allowed, and well, their days are numbered.

There are lots of other mechanical tilt switches, many have gold plated balls in an inert gas tube, others are the old fashioned pedulum type.
Comus International stocks many varieties.

The biggest problem in the mechanical replacements is the lack of inertia inherent in the mecury type. One little jiggle and contact is lost. Major hassle in many designs :evil: One of my products at work went from a 50 cent mercury switch to a ball type switch, latching an SCR via one-shot circuit, time delay for hysterises, blah blah blah, ends up being a complicated 30 dollar replacement... not very elegant.

rant over....

 

[Adum Chan]

Thank you all for valuable information, I understand the situration now. So CdS will disappear in the market shortly ?!

Gorgon,

My application is a toy room guard they require to detect if any body movement in front of 2m - 3m of the device, do you have any suitable cct using photo transistor ?

 

[spuffock]

I have an application that requires a photoconductor. No cadmium will be a pig to deal with. Are we still allowed selenium?
Come to that, will I still be able to get a sharp knife? What about access to boiling water?

 

[audioguru]

Come to that, will I still be able to get a sharp knife? What about access to boiling water?

Hide your knife and boiling water so the cops can't take them away from you!

When I was young, a friend was killed from inhaling nitro-benzine that we added to the alcohol fuel for our model airplanes. It was freely and cheaply available to kids at the pharmacy. :cry:
We also got some iodine-stuff from the pharmacy that made great explosives! :lol:

Can't do dat now, they're banned.

 

[spuffock]

I,ve got half a kilo of iodine. Trouble is, I cant think of much use for it.
(And a couple litres ammonia)

 

[Styx]

I,ve got half a kilo of iodine. Trouble is, I cant think of much use for it.
(And a couple litres ammonia)

I have a couple of uses, will have to wait till nx years bonefire night tho