Free solenoid coils.

[DICKEYBIRD]

I had to chip away at my "Honey-Do" list yesterday and fix SWMBO's washing machine. Unfortunately, there's no crick (creek to you carpet-baggers) within walking distance to wash clothes in. So, off to the over-priced Maytag parts depot I went for a timer, a water valve and a lid switch.

I don't throw anything away without 1st running all the permutations on possible future use of the old parts. The water valve had 2 nifty little 110v solenoids and the failure was a leaky valve; electrically the coils were fine.

With a little prying, I had the coils off and just had to play with them. They measure 1115 ohms so I figger that's about .1 amp and 12w. You sparkies can straighten me out if I'm way wrong...I gets corn-fused when dealing with AC stuff. I powered one up with a patch cord and played around with a piece of 3/8" CRS. It was a little small but I could feel the solenoid suck it in when the power was switched on. Not real strong but usable I think. Should do even better with a soft iron "piston" that fits better. You could feel it get warm after a few minutes but not excessively.

I think they would probably work on a small, 2 "cylinder" low friction solenoid engine. The price was right anyway. If they are indeed useful, I'll bet a feller could get all he wants for a six-pack at the local appliance repair shop.

 

[Bluechip]

Hi

If it's an AC solenoid coil you need to do this to the core. It's copper, called a 'slug' or similar.

This is 36V AC 50 Hz - Res. is 240 Ohms.

First pic post so I'll probably kybosh the thing ;D

dave

Edit .. Gorblimey -- it works, will buy a Lottery Ticket while me lucks in !!

 

[DICKEYBIRD]

OK...what does it it do? Like Ricky Ricardo said: "...s'plane it to me Lucy." ;D

 

[Bluechip]

Hi DB

I did my electrical theory at Tech. circa 45 yrs ago. Generally speaking the copper bit will act as a 'shorted turn' and will have a electric current induced in it. This will produce a second magnetic field interacting with the coil field, I guess. This reduces the tendency of the core to vibrate, I've dealt with hundreds of AC contactors and solenoids, they all seem to have a arrangement similar to the pic. Some times a copper 'rivet' standing slightly above the core.

Big contactors that have a laminated cores and a laminated armatures, [ the thing that gets attracted to it ]. They don't have them as far as I know. But laminated cores don't [ or shouldn't ] vibrate. Solenoids with a solid armature/plunger/core seem to be slugged by some means.

I probably had a vague understanding years ago, but it has not improved over the years ;D

I just use the wretched things, DB, I presume the geezers who make 'em know what they're doing. ;D

I'll have a google, maybe a simple explanation on Wikki or whatever.

What's the coil voltage on yours? -- 110V ? Will very likely make a Solenoid engine on a lot lower DC supply

Dave

 

[DICKEYBIRD]

Thanks Dave. The depth of my knowledge in most things electrical can be measured in thousandths.

 

[Bluechip]

Hi DB

Called a 'Shading Coil' --- look at this, about 6 posts down.

http://www.control.com/thread/1026232445

At least someone knows

I was about 70% right, rest waffle, I'm still good at that

Dave

 

[wareagle]

For a quick down and dirty explanation of the shading coil, it's purpose in life is to keep the solenoid quiet. These exist only on AC solenoid coils, and if this shading coil circuit is open, then the solenoid will have a noticable buzzing/humming noise. If there is a loss of the shading coil, the solenoid will still function just fine, it just lets you know, "Hey, I have voltage here" by making noise like a smal transformer.

The shading coil is common to any AC solenoid valves, actuators, contactors and starters.