How much mercury is in mercury relays?

[Ignoramus29535]

(not completely idle interest)

I was just wondering, how much mercury is in mercury relays such as 80
amp three pole relays. A website claims that even a 35 amp single pole
relay contains 251 grams of mercury, which is hard to believe.

http://goo.gl/ESvOvC

[Paul Drahn]

Probably true. But it is encapsulated in glass. You have probably
already seen: https://en.wikipedia.org/wiki/Mercury_relay.

They seem to operate just like the older thermostats. Arcing of the
contacts will vaporize some of the mercury, but it is recovered when the
switch cools.

Paul

[Ignoramus29535]

Right. But I want to know how much of it is there. I bought a cabinet
with contents, with big mercury relays. When I shake them, I feek a
significant "heft" of liquid inside.

i

[Lloyd E. Sponenburgh]

Ignoramus29535 <ignoram...@NOSPAM.29535.invalid> fired this volley in
news:mu-dnQXeg7QULkXP...@giganews.com:

> Right. But I want to know how much of it is there. I bought a cabinet
> with contents, with big mercury relays. When I shake them, I feek a
> significant "heft" of liquid inside.

Ig, at 7.6g/cc, it would take 33cc of mercury to make up 251g.

That's a half-pound! (which ain't a huge volume. I've got a 1lb bottle
of Hg that's only the size of a small pill vial).

I've have a lot of different single-pole mercury tilt switches, with the
biggest one rated at 30A. It doesn't have more than about 2cc of the
metal in it.

Think about it... 11cc per pole is 2-1/4 teaspoonsful per pole. (Although
you probably think 'naturally' in metric volumes, some of us have to
translate to Imperial to 'get it'.<G>) That seems like a great deal.

Now... if they were 100A switches/relays, I could see maybe having that
much in them, just to increase the contact area, so they don't get hot.

But that sounds like too much for 35A jobs.

Lloyd

[Jim Wilkins]

"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message
news:XnsA2B845CCDF771ll...@216.168.3.70...

>
> Ig, at 7.6g/cc, it would take 33cc of mercury to make up 251g.
>

> Lloyd

Read the Wiki more carefully. The coin shown floating on mercury has a
density of 7.6g/cc, mercury's is 13.534.
jsw

[Lloyd E. Sponenburgh]

"Jim Wilkins" <murat...@gmail.com> fired this volley in news:lbb7nt$1au$1
@dont-email.me:

> Read the Wiki more carefully. The coin shown floating on mercury has a
> density of 7.6g/cc, mercury's is 13.534.

Correct! That would make it something over a teaspoonful per contact.
Still a lot, but about half of what I wrote.

LLoyd

[Larry Jaques]

On Thu, 16 Jan 2014 22:04:32 -0600, Ignoramus29535
<ignoram...@NOSPAM.29535.invalid> wrote:

>(not completely idle interest)

You piqued mine, too.

>I was just wondering, how much mercury is in mercury relays such as 80
>amp three pole relays. A website claims that even a 35 amp single pole
>relay contains 251 grams of mercury, which is hard to believe.
>
> http://goo.gl/ESvOvC

I like their wording. "contains about 251.6 grams." Since when does
"about" go down to tenths of grams? <g>

Mercury is exceedingly dense and heavy at 13534 kg/m3, but ~9oz does
seem overly much for a small, single-pole relay. (I wonder if it's a
weight v. volume mismatch I'm experiencing. I believe so.)

1 fluid ounce (fl oz) of mercury = 0.88 lb in mercury

So 252 grams would be roughly 0.64 fluid ounces. OK, that works for
me. That crap IS dense!

--
Education is that which remains when one has
forgotten everything he learned in school.
--Albert Einstein

[Ignoramus23003]

I will try to open one up and see. I will do it outdoors

i

[Larry Jaques]

The EPA goons are likely on their way to your house as I type this...

[dpb]

On 1/17/2014 9:19 AM, Larry Jaques wrote:
...

> Mercury is exceedingly dense and heavy at 13534 kg/m3, but ~9oz does
> seem overly much for a small, single-pole relay. (I wonder if it's a
> weight v. volume mismatch I'm experiencing. I believe so.)
>
> 1 fluid ounce (fl oz) of mercury = 0.88 lb in mercury
>
> So 252 grams would be roughly 0.64 fluid ounces. OK, that works for
> me. That crap IS dense!

...

Yes, it's 20% more dense than Pb -- 13.6 vs 11.3 gm/cm^3

--

[Jon Elson]

Just shake it! You can probably feel the mercury sloshing around
in there. Yes, the huge old mercury contactors had an amazing
amount of the stuff in them.

Jon

[Paul Drahn]

I think more mercury would be required if the switch was activiated many
times per minute, at the rated amperage. Much more vapour would be
produced during the time of contact arcing.

Paul

[Ignoramus23003]

On 2014-01-17, Paul Drahn <pdr...@webformixair.com> wrote:

Paul, I believe that this is what these switches are for, for very
frequent switching.

i

[azotic]

"Ignoramus23003" <ignoram...@NOSPAM.23003.invalid> wrote in message
news:yJCdnUQY5KRFAETP...@giganews.com...

They are also used in explosion proof applications where a
contact arcing in a normal relay could be an ignition source.

Best Regards
Tom.
--
http://fija.org/

[Lloyd E. Sponenburgh]

"azotic" <H.B...@network.com> fired this volley in news:lbcc1r$9al$1
@speranza.aioe.org:

> They are also used in explosion proof applications where a
> contact arcing in a normal relay could be an ignition source.
>

Really? I'd like to know more about that. Any citations?

Lloyd

[Howard Beal]

"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message
news:XnsA2B8B7BA2EAAEll...@216.168.3.70...

Read it in a manufactures literature many years ago.
Don't remember who, might have been magnacraft.

Best Regards
Tom.

[DoN. Nichols]

As a kid, I used to reclaim Mercury from such relays, and
remember that Mercury is quite dense compared to a similar volume of
steel. Have you ever lifted a bottle filled with it?

This site:

<http://www.enotes.com/homework-help/what-density-mercury-kg-m-3-what-its-density-g-cm-124349>

says: "The density of mercury = 13534 kg/m^3 or 13.534 gram/cubic
centimeter"

so that would be 18.546 cc, or a cube (if you froze it) 2.64 cm on a
side (a bit over an inch). That is fairly close to my experience. So
an 80 Amp three pole would probably be on the order of 1,694 gm (making
perhaps unjustified assumptions on the needed increase in size), or
about 3/4 of a pound.

The relay needs quite a bit of mercury to handle the current,
since *it* is the conductor, and if you have too little of it, it will
vaporize (and possibly shatter the container if it is an all-glass one
(some are, some are not.) Mercury wetted reed relays, in contrast, use
a tiny drop, which simply wets both contacts, and make a clean
connection quickly when it closes, and does not suffer from contact
bounce.

Sort of somewhere between those two are the old home
thermostats, which used a small ball of it rolling around in a glass
tube to short the contacts when it tilts one direction, and open them in
the other direction. (The rolling mass of mercury also adds a bit of
hysteresis to the operation of the switch -- something which I had not
realized until I started typing this. :-)

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: <BPdnic...@d-and-d.com> | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

[Lloyd E. Sponenburgh]

"DoN. Nichols" <BPdnic...@d-and-d.com> fired this volley in
news:slrnldjkjq.1m...@Katana.d-and-d.com:

> Have you ever lifted a bottle filled with it?

A quart glass milk bottle of it in the 1960s -- Yes, it's heavy!


I still have a 1lb bottle (a mere 'vial', and shy a few grams) of
chemically-pure mercury which I use in tiny quantities for compounding
experiments (not electrical purposes).

Lloyd

[Joe Gwinn]

In article <8sSdnZ7-GeSS1kTP...@giganews.com>,

The standard remedy for spilled mercury when I was in high school was
flowers of sulfur, which is finely divided elemental sulfur. This
combines with the mercury to yield the sulfide, which is the ore.

The EPA is nutso about mercury. I handled a lot of it when I was in my
teens. Nothing bad happened.

Joe Gwinn

[Jon Elson]

Ignoramus23003 wrote:


> Paul, I believe that this is what these switches are for, for very
> frequent switching.

Really old DEC computers used them. I guess the problem was the
possibility of the turn-on surge welding the contacts of traditional
contactors, and the mercury contactors were pretty immune to
that. This was in the PDP-8 days of the 1960's.

Jon

[Ignoramus23003]

On 2014-01-18, DoN. Nichols <BPdnic...@d-and-d.com> wrote:
> As a kid, I used to reclaim Mercury from such relays, and
> remember that Mercury is quite dense compared to a similar volume of
> steel.

How did you reclaim them? Were they glass or epoxy encapsulated?

> Have you ever lifted a bottle filled with it?

Yes. Feels odd.

i

[Ignoramus23003]

On 2014-01-17, Larry Jaques <lja...@invalid.diversifycomm.com> wrote:
>
> The EPA goons are likely on their way to your house as I type this...
>

Read this story. It is about an ignorant scrapper Bret A. Simpson, who
bought a Liberty ship, hired a bunch of ignorant workers to cut it up,
did not check that the ship contained hundreds of tons of used oil and
other hazmat.

http://www.ecy.wa.gov/programs/spills/incidents/DavyCrockett/DavyCrockett.html

The ship broke/cracked due to some I-beams having been cut, and that
caused its tanks to rupture and leak oil into the water. Bret Simpson
ran away after trying to contain oil with booms, and the abandoned
ship shitted the whole river with oil etc. He had a prior felony
conviction for burying barrels with hazmat on his property (great guy
obviously, with a history of caring for the environment).

What was his sentence? Four months of prison.

I honestly think that it is not too much.

i

[Larry Jaques]

I don't understand. They've given much longer sentences to people who
accidentally spilled a quart or two of oil on their property.

>I honestly think that it is not too much.

Castrate him so it is never passed on?

[jim]

Larry Jaques wrote:
>
> On Fri, 17 Jan 2014 22:05:51 -0600, Ignoramus23003
> <ignoram...@NOSPAM.23003.invalid> wrote:
>
> >On 2014-01-17, Larry Jaques <lja...@invalid.diversifycomm.com> wrote:
> >>
> >> The EPA goons are likely on their way to your house as I type this...
> >>
> >
> >Read this story. It is about an ignorant scrapper Bret A. Simpson, who
> >bought a Liberty ship, hired a bunch of ignorant workers to cut it up,
> >did not check that the ship contained hundreds of tons of used oil and
> >other hazmat.
> >
> >http://www.ecy.wa.gov/programs/spills/incidents/DavyCrockett/DavyCrockett.html
> >
> >The ship broke/cracked due to some I-beams having been cut, and that
> >caused its tanks to rupture and leak oil into the water. Bret Simpson
> >ran away after trying to contain oil with booms, and the abandoned
> >ship shitted the whole river with oil etc. He had a prior felony
> >conviction for burying barrels with hazmat on his property (great guy
> >obviously, with a history of caring for the environment).
> >
> >What was his sentence? Four months of prison.
>
> I don't understand. They've given much longer sentences to people who
> accidentally spilled a quart or two of oil on their property.

I'm pretty sure the death sentence is mandatory for anything over
a quart. I read it on the internet so I know its true.

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

[Bob Engelhardt]

On 1/17/2014 10:19 AM, Larry Jaques wrote:
> ...I wonder if it's a
> weight v. volume mismatch I'm experiencing. ...

Yeah, me too. It's our conditioning with water, I think. With water,
ounces weight and ounces volume are the same. So, I see "9 ounces"
(weight), I tend to visualize that as 9 ounces volume. 99.9% of time
when it's water or a close cousin, it works. With mercury, not so much <G>.

Bob

[Bob Engelhardt]

On 1/17/2014 9:17 PM, Lloyd E. Sponenburgh wrote:

> A quart glass milk bottle of it in the 1960s -- Yes, it's heavy!

...

Let's see: it's 13 times the density of water; 2 lbs of water per quart
= 26 lbs of mercury per quart. A 2-handed effort. Bob

[DoN. Nichols]

On 2014-01-18, Ignoramus23003 <ignoram...@NOSPAM.23003.invalid> wrote:
> On 2014-01-18, DoN. Nichols <BPdnic...@d-and-d.com> wrote:
>> As a kid, I used to reclaim Mercury from such relays, and
>> remember that Mercury is quite dense compared to a similar volume of
>> steel.
>
> How did you reclaim them? Were they glass or epoxy encapsulated?

Some of each. The glass was broken in a container, and then the
glass (which floated on the mercury) could easily be picked off.

The other I just hacksawed until the mercury would pour out.

>> Have you ever lifted a bottle filled with it?
>
> Yes. Feels odd.

A lot heavier than it has any right to be. :-) (Of course so are
gold and depleted Uranium. I've also once picked up a bottle of "heavy
water" (Deuterium Oxide) -- and yes, it, also, is notably heavier than
you would expect. (And no -- I have no idea why that lab at work had a
bottle of it -- but they did. :-)

[Martin Eastburn]

They would pass a lot more current and do not arc.
They were required to be in the operating position for some time
unless they have heaters.

Martin

[Ignoramus20572]

John, are you talking about mercury-wetted relays, or mercury relays?
They are different animals entirely.

i

[Ignoramus20572]

On 2014-01-19, DoN. Nichols <BPdnic...@d-and-d.com> wrote:
> On 2014-01-18, Ignoramus23003 <ignoram...@NOSPAM.23003.invalid> wrote:
>> On 2014-01-18, DoN. Nichols <BPdnic...@d-and-d.com> wrote:
>>> As a kid, I used to reclaim Mercury from such relays, and
>>> remember that Mercury is quite dense compared to a similar volume of
>>> steel.
>>
>> How did you reclaim them? Were they glass or epoxy encapsulated?
>
> Some of each. The glass was broken in a container, and then the
> glass (which floated on the mercury) could easily be picked off.
>
> The other I just hacksawed until the mercury would pour out.
>
>>> Have you ever lifted a bottle filled with it?
>>
>> Yes. Feels odd.
>
> A lot heavier than it has any right to be. :-) (Of course so are
> gold and depleted Uranium. I've also once picked up a bottle of "heavy
> water" (Deuterium Oxide) -- and yes, it, also, is notably heavier than
> you would expect. (And no -- I have no idea why that lab at work had a
> bottle of it -- but they did. :-)

I do not have any gold, but I have a piece of tungsten, which weighs
as much as a similar piece of gold, and it does feel odd. Of course
after collecting appx. 45 lbs of carbide scrap, it does not feel so
unusual any more.

i

[whit3rd]

On Friday, January 17, 2014 7:23:59 AM UTC-8, Ignoramus23003 wrote:
> On 2014-01-17, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:

> I will try to open one up and see. I will do it outdoors

Why? That'll ruin an expensive relay.