Brass contacts?
Brass contacts?
(OP)
Hi all,
we use a design where we have open face brass contacts for level switching control in a shaft, we now want to make our product suitable for external use,
my concern is the possible reaction of this material and rain water, the brass switch plates/plunger carry 24v dc,
are there any possible electrolysis effects too?
thanks
Dave
we use a design where we have open face brass contacts for level switching control in a shaft, we now want to make our product suitable for external use,
my concern is the possible reaction of this material and rain water, the brass switch plates/plunger carry 24v dc,
are there any possible electrolysis effects too?
thanks
Dave





RE: Brass contacts?
DC huh?
What kind of shaft?
Switching rate?
Full submersion?
Only rain or hose water too?
Any gases present?
RE: Brass contacts?
switch rate = milliAmps
not full submersion
only rain water
is a lift shaft
no gases
RE: Brass contacts?
I don't see any problem. 24V will fry off any oxides that form and the brass-to-brass contacts should not plate one to the other. If the water is dirty you could always end up with non conductive material being carried onto the contact points then causing a problem. You might need to consider this ..or not. Perhaps orientation needs to be considered
RE: Brass contacts?
thanks, cant find any real adverse info from web searches for brass, my only thought is similar to yours, where the plunger/plate could beacome tarnished over time in an external environment, and possibly create a high impedance contact
RE: Brass contacts?
Gunnar Englund
www.gke.org
RE: Brass contacts?
I remain,
The Old Soldering Gunslinger
RE: Brass contacts?
<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032
RE: Brass contacts?
Silver or silver-plating would probably be more better.
In the electric utility world, we find 125 V dc very effective at punching through any crud that might build up on seldom-used contacts
RE: Brass contacts?
The reed switch is a good idea too! But I suspect you are switching a relay or something that takes too much current.
RE: Brass contacts?
"I might be a little concerned if this was an application where the contacts stayed open for years and years, then had to work reliably when closed. But if the contacts close once in a while, you're probablyh OK. "
this is my concern, the 'contacts' are open, because it is an inhouse design for level control,
RE: Brass contacts?