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default
Guest

Thu May 10, 2018 12:45 am   



On Wed, 9 May 2018 17:45:30 -0000 (UTC), Cursitor Doom
<curd_at_notformail.com> wrote:

Quote:
On Mon, 07 May 2018 16:59:18 -0400, default wrote:

I don't ever remember seeing duty cycle as a spec on any relays.

That's why I put it in inverted commas! The essence of it is, you will
have no trouble provided you energise your solenoid in well-spaced, short
bursts. Used that way it should last for years. If you hold it constantly
on, however, it'll burn out within 2-3 minutes.

Current and voltage for the contacts, nominal voltage for the coil and
must make must release voltages, and mechanical/environmental, number of
cycles, are all the specs you usually get.

Some people think they can save a small fortune by using auto solenoids
in place of the correct ones in applications like winches. They don't
realise it's the extended 'on' time capability that you're paying for.
Auto starter solenoids are NOT designed for what amounts to continual
duty and the manufacturers simply assume (not unreasonably) that you will
not use them for anything other than their stated purpose!


Oh.. I only mention the solenoid because it is on the load side of
one of the ice-cube size small relays. I realize the actual starter
solenoid is a whole 'nother thing.

The tiny relays are rated for a 40 amp load and the contacts
eventually burn. They switch the starter solenoid, AC clutch, and
fuel pump. Strangely enough, the headlight and horn are wired direct
without relays.

Cursitor Doom
Guest

Fri May 11, 2018 5:45 pm   



On Wed, 09 May 2018 19:31:26 -0400, default wrote:

Quote:
Oh.. I only mention the solenoid because it is on the load side of one
of the ice-cube size small relays. I realize the actual starter
solenoid is a whole 'nother thing.


Oh, right. Sorry, I didn't read your original question correctly, then.
What they *may* have done is to silver pad the contact points. Silver has
a marginally lower electrical resistance than copper, but you would not
notice without specifically looking at the contact areas.


Quote:
The tiny relays are rated for a 40 amp load and the contacts eventually
burn. They switch the starter solenoid, AC clutch, and fuel pump.
Strangely enough, the headlight and horn are wired direct without
relays.


Horn, no surprise. Doesn't use much current. Headlamps, yes, that is
'unusual' shall we say. I can't say I've ever come across that.





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Guest

Fri May 11, 2018 8:45 pm   



>"Silver has a marginally lower electrical resistance than copper"

Something like 3.5 % only. While I was unable to get a specific figure on the electrical conductivity of silver oxide, it is said to be almost as conductive as silver, and is self limiting in thickness. Gold is not really a great conductor but it almost can't oxidise or anything, so if the coating is thin enough it works fine. Copper oxides and compounds are pretty much insulators so that, why there is plating. In my recent internet travels someone mentioned the palladium would work well. That may be but I don't know what it costs. Gold is not necessarily the most expensive substance on Earth.

Jasen Betts
Guest

Sat May 12, 2018 1:45 am   



On 2018-05-11, jurb6006_at_gmail.com <jurb6006_at_gmail.com> wrote:
Quote:
"Silver has a marginally lower electrical resistance than copper"

Something like 3.5 % only. While I was unable to get a specific figure on the electrical conductivity of silver oxide, it is said to be almost as conductive as silver, and is self limiting in thickness. Gold is not really a great conductor but it almost can't oxidise or anything, so if the coating is thin enough it works fine. Copper oxides and compounds are pretty much insulators so that, why there is plating. In my recent internet travels someone mentioned the palladium would work well. That may be but I don't know what it costs. Gold is not necessarily the most expensive substance on Earth.


gold, palladiun, and platinum all cost about the same, currently gold
seems to be the most expensive of the three.

--
ت

Phil Allison
Guest

Sat May 12, 2018 3:45 am   



jurb...@gmail.com wrote:
Quote:


"Silver has a marginally lower electrical resistance than copper"

Something like 3.5 % only. While I was unable to get a specific figure
on the electrical conductivity of silver oxide, it is said to be almost
as conductive as silver,



** The tarnish that forms on silver is "silver sulphide" - an insulator.

Being soft, it polishes or wears off fairly easily.


..... Phil


Guest

Sat May 12, 2018 7:45 am   



>"** The tarnish that forms on silver is "silver sulphide" - an insulator. "

So if you got acid rain your silver is brown ? lol

I read about it being sulpher and not oxygen but where does it get the sulphur ? In a metropolitan area I can see where (almost literally) but in normal places fit for human habitation, there is probably not much sulphur in the air.

I thought the major source of SO2 in the air was burning of shitty fossil fuels like cheap coal.

+++ATH0
Guest

Mon May 14, 2018 5:45 am   



On 2018-05-11 23:40, jurb6006_at_gmail.com wrote:
Quote:

I thought the major source of SO2 in the air was burning of shitty fossil fuels like cheap coal.


Sulphur is one of the most abundant elements, and is essential to pretty
much all life on Earth. It's not just farts and Chinky coal.

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