Silver plated connectors, could be considered a health hazard in the lab?

[neazoi]

Hello,
I have opened another thread about beryllium copper connectors and health hazards. This time I would like to ask about silver-plated connectors.

Are they considered a health hazard in the laboratory?
After all, people are wearing silver (aloy?) rings and they are considered skin-friendly.
I am talking about the pure silver, but also the silver oxides (I,II,II) that may be formed when the connector gets a bit rusty.
How yould you judge the health hazard (if any) compared to the beryllium copper containing connectors?

 

[D.A.(Tony)Stewart]

BeCu is superior for elastic and low-oxidizing performance.
Silver particles are known to be antiseptic, but also when oxidized become insulators, so cleanliness of contacts is hard to achieve when frequently disconnected, but for torqued permanent connections make a gas tight fit. This is why gold plated connectors are preferred for RF. For audio, due to high impedance, it is overkill.

- also gold plating can be flashed to 1u" in cheap connectors so torque specs are critical not to exceed, otherwise use more expensive 10-30u" plated connectors.

 

[volker@muehlhaus]

health hazard in the laboratory?

Absolutely. If not used with caution, a silver knife might kill you.
https://robbeberking.com/en/shop/collections/silver-and-silver-plated-cutlery.html

 

[FvM]

You are comparing incomparable things.

For connectors, silver is a surface plating, used alternatively to gold or nickel. Connector case material is brass or zinc die cast, for small connectors also stainless steel. Copper beryllium alloy (CuBe) is exclusively used for contact springs, e.g. for the female inner connectors, and has always a surface plating of another material, e.g. gold. Silver is too soft to be used for contact springs.

 

[neazoi]

You are comparing incomparable things.

For connectors, silver is a surface plating, used alternatively to gold or nickel. Connector case material is brass or zinc die cast, for small connectors also stainless steel. Copper beryllium alloy (CuBe) is exclusively used for contact springs, e.g. for the female inner connectors, and has always a surface plating of another material, e.g. gold. Silver is too soft to be used for contact springs.

Ah thanks, so CuBe is used for elasticity basically, inside the part, not plated to it.
Ok talking about silver, I basically meant silver plating, so indeed these are not directly comparable.
However I primarily considered material safety, not properties and as far as I can understand from the previous posts silver and some oxides are relatively hazard-free, despite of the things written on the net.
Of course you are not going to eat the silver oxide, but you know how things are sometimes. sometimes you are struggling with a circuit problem and you examine closely the circuit and there is a chance that you get some "unwanted" particles.
Anyway, recently I acquired these **broken link removed** and they have both conductors silver plated. I do not know what is inside the core of the metals, however these seem vintage russian mill parts, I do not know if they have used CuBe back then.

Most of my silver plated connectors remain intact, except the ones that I touch with wet fingers and if humidity is high enough in some rooms.
I have also noticed that connectors of this type that remain connected for long time (male to female connected) remain intact at the point they were connected, whereas at the point where they were not connected they get more rusty.
Seeing this, I believe a connector plastic cover is worth it if connector is not used for long periods.

 

[D.A.(Tony)Stewart]

These are OK to use but will have quality issues near/beyond 1GHz

Good ones have gold plating.... and cost more..

 

[volker@muehlhaus]

but will have quality issues near/beyond 1GHz

Why do you think so?

 

[neazoi]

These are OK to use but will have quality issues near/beyond 1GHz

Good ones have gold plating.... and cost more..

Quality issues?
Silver has greater conductivity than even pure gold, not to mention that some support that one of the silver oxides has even better conductivity.

 

[FvM]

Silver contacts have problems in when exposed to sulfur compounds like hydrogen sulfide, forming a black, semiconducting layer of silver sulfide.

 

[neazoi]

Silver contacts have problems in when exposed to sulfur compounds like hydrogen sulfide, forming a black, semiconducting layer of silver sulfide.

This black layer has to be avoided, as this is the non-conductive oxide. The other oxide (yellowish-silver), which I do not remember it't name, is super conductive as some say. I have noticed that this can be formed if using these commercial silvery cleaning solutions. At first the silver is cleaned but then it needs constant cleaning. Also if you touch the contacts too much and because of increased humidity. I have seen that silver connectors need care from dust and humidity. Plastic protective cups, when mountet on panels, are a must if one needs the connector to be clean for long time.
As far as I see from material safety datasheets silver sulfide presents not signifficant health issues, in lab use.

 

[D.A.(Tony)Stewart]

Connectors must be incredibly tight machined tolerances since ratios of outer/inner radius affect impedance at every frequency. Dielectric constant of plastic can vary 10% easily from batch to batch without quality controls and feedback to tune this. E.g. PVC,PP,PU,Teflon. Most Likely these are PVC.

This becomes become more sensitive to Return Loss starting at ~ 1/10 wavelength or about the size of a BNC connector.


Connectors with <10 db return loss at 1GHz are cheap. Untested knockoffs are likely worse.

How much did you pay for these parts with no specs, brand name or manufacturer?


Nuff said.

 

[neazoi]

Connectors must be incredibly tight machined tolerances since ratios of outer/inner radius affect impedance at every frequency. Dielectric constant of plastic can vary 10% easily from batch to batch without quality controls and feedback to tune this. E.g. PVC,PP,PU,Teflon. Most Likely these are PVC.

This becomes become more sensitive to Return Loss starting at ~ 1/10 wavelength or about the size of a BNC connector.
Connectors with <10 db return loss at 1GHz are cheap. Untested knockoffs are likely worse.
How much did you pay for these parts with no specs, brand name or manufacturer?
Nuff said.

These will be used on HF <30MHz, a bare wire would probably suffice.
I would use aeroflex or similar SMA or even HP APC-7 for greater frequencies.

 

[volker@muehlhaus]

Connectors must be incredibly tight machined tolerances since ratios of outer/inner radius affect impedance at every frequency. Dielectric constant of plastic can vary 10% easily from batch to batch without quality controls and feedback to tune this. E.g. PVC,PP,PU,Teflon.

True, but totally unrelated to silver plated surface.

This becomes become more sensitive to Return Loss starting at ~ 1/10 wavelength or about the size of a BNC connector.

True, but totally unrelated to silver plated surface.

Connectors with <10 db return loss at 1GHz are cheap. Untested knockoffs are likely worse.

True, but totally unrelated to silver plated surface.

parts with no specs, brand name or manufacturer?

The silver plated connectors and silver plated resonators that I purchased long ago as surplus items had been from military radio systems. I don't think that silver plating the entire connector indicates cheap no-name products.

 

[neazoi]

The silver plated connectors and silver plated resonators that I purchased long ago as surplus items had been from military radio systems. I don't think that silver plating the entire connector indicates cheap no-name products.

The connectors I have posted in previous post are mil-spec whole body and central conductors silver plated types.
Man you do not need to see specs to compare them at least with these cheap Asian connectors...
Sometimes with a quick look at an electronics part, you can say if this is high quality one or not, independent of tight specs.
Look at some vishay parts or switchcraft connectors for example.
Of course specs should be always looked up at the end, when they are available.