Mercury wetted or ruthenium for reed relay?

mzzj

Member
2005-07-02 8:17 pm
65N 25E
Wich one is better for line-input and attenuator reed-relays?

ruthenium sputtered ones are usually specially mentioned as dry-switcing and Hg wetted are more robust workhorses, but i think Hg ones should be suitable also for small signals.

Is there some thermoelectric voltage issue with Hg or why it is not usually specified for small-signal use? (not a problem in audio equipment but maybe in measurement systems)

I located a source for CP-Clare mercury wetted and ruthenium sputtered reed relays for 0.35 and 0.42 euros apiece so I am not even thinking about Elnas rotary switches anymore.
 
> I located a source for CP-Clare mercury wetted and ruthenium sputtered reed relays for 0.35 and 0.42 euros apiece

Are they new or removed from used equipment?

Clare mercury wetted relays (DPDT, 2A, shielded) cost US$ 120- per piece from Newark, new !!!!

If I were you, I'll get them now. From 2006, they are banned from import into Europe (poisonous to environment).


Patrick
 

mzzj

Member
2005-07-02 8:17 pm
65N 25E
EUVL said:
Are they new or removed from used equipment?

Clare mercury wetted relays (DPDT, 2A, shielded) cost US$ 120- per piece from Newark, new !!!!

If I were you, I'll get them now. From 2006, they are banned from import into Europe (poisonous to environment).

Patrick [/B]
New, but probably some sort of industry surplus. Couple of years old anyways as CP-Clare is not manufacturing relays anymore.

Enviromental regulations might be one reason why they are cheapish, Nokia is dumping their uncompatible stock to surplussales.
 

mzzj

Member
2005-07-02 8:17 pm
65N 25E
EUVL said:
Could you disclose the source ? I would love to get some.
You can email me at [email protected]

Thanks,
Patrick
Have to order my own relays first :D

I am not sure if they are willing to do business abroad, this is small Finnish company.

I could probably sent some of them for you to germany, Preferably by multiples of 35 pieces. Postal costs should be minor and money transfer within EU is free of charge.
 
OK. Not the best specs I have ever seen (contact resistance 100mohm), but what the hack at that price. I'd take 35 pcs of the mercury wetted (CUPV60202) if you wouldn't mind the trouble. Please send me a email so that we can sort out the rest.

Also please kindly give me an estimate for the postage to Germany before ordering (I would guess something like 5 Euros, but you never know).


Thanks,
Patrick
 
One thing to check for with the Hg ones is the mounting posistion. Some of them can only be used in a certain position.

The main reason for the development of the ruthenium sputtered contact types is the fact that the Hg ones are environmentally bad news, both in production as well as after discarding.

I have used many years Pickering type 101 ruthenium types for audio switching without any apparent problems.

Jan Didden
 
are concentrating on gold-plated power poles and bulk-foil caps......


I always response when someone calls me by name :)

It may be quite unrelated but here is my recent experience with relays.

I ordered some Nais relays thinking that if they are good enough for CJ Art they are probably good enough for me. First audition was of the normally closed set of contacts. Dunno if they stayed closed for too long and melted together but i could hardly tell there was anything new in the signal chain. Not so with the other pair which needed the coil to be energised. It may be the magnetic field or the way the contact surfaces press together - i have no idea, but it didn't sound too good.

After looking at the ART pics again i noticed the Nais type CJ use are latching so magnetic field is only applied at the moment of switching.

Could it be the latching principle is more important than the type of contact?
 

mzzj

Member
2005-07-02 8:17 pm
65N 25E
janneman said:
One thing to check for with the Hg ones is the mounting posistion. Some of them can only be used in a certain position.

The main reason for the development of the ruthenium sputtered contact types is the fact that the Hg ones are environmentally bad news, both in production as well as after discarding.

I have used many years Pickering type 101 ruthenium types for audio switching without any apparent problems.

Jan Didden

Ok, these ones are not sensitive to mounting position, I guess that there is only minuscule amount of mercur on contact surfaces, not entire pool like some other types.

Mercury content of these is sooo small compared to all those fluorescent lamps everywhere that I am not going to lose my sleep over that. Dunno, maybe these are not so good then as these have so little mercury
:)