Mystery Item thread.... What am i?

[Darkwood]

This is out of an old Russian lathe it has 4 contacts on it 2 x NC and 2 x NO it has a coil and on top it has a sealed oil filled reservoir.
What is its function!

Spoiler alert!!! Answer in post 9!!!

 

[Darkwood]

Voltage stabiliser ?

 

[Silly Sausage]

Got to be monitoring current!....somehow

Show more piccy!

 

[GLENNSPARK]

No, you can't measure anything with it, although this part is a kind of sensor that detects something changing.

angles?...
their looks to be a fulcrum on it Lucien...

 

[vad25]

View attachment 20004View attachment 20005 This is out of an old Russian lathe it has 4 contacts on it 2 x NC and 2 x NO it has a coil and on top it has a sealed oil filled reservoir.
What is its function!

Spoiler alert!!! Answer in post 9!!!

It's time delay relay how I can remember

 

[DPG]

A shunt? Daz

 

[Lucien Nunes]

Bloke puts his suit on, presses a button, 50 feet above him the box does its job. He sits down and waits for his signal. When he gets it he presses another button, begins his work and goes up.

 

[Darkwood]

Anything to do with a bridge or a dam of some nature???

 

[Lucien Nunes]

No, getting colder. Here's the top part. It's 3-phase but never electrically connected to the mains. 20A at 270V is its rating according to the brass plate, but it doesn't have to withstand the full voltage for long. In fact, for most of the time, the voltage is zero. It certainly needs to be zero by the time the chap I mentioned presses his second button, or the results will be disappointing.

 

[Darkwood]

edit just re-read ....having some thunking time (yorkshire for thinking )

Some kind of charging/discharging unit the second button maybe for a crowd pleaser effect ( Flash or arc)

If its not connected to the mains directly then its energised from maybe a generator that is charging something up at 0volts the unit give full resistance to discharge and the bloke pushes the button for instant discharge ...... i could be a mile off here but i would say maybe a stage effect or something similar.

We use a similar device as above with one wiper and is operated off dancers to give speed control to DC motors and give unity speed between motors down the line.

 

[Lucien Nunes]

You were right the first time! It IS a starter, but why is it like it is? What's in the bottom box that operates the rheostat? Here's a picture of the motor, not sure that tells you very much but it's a 12hp Crompton Parkinson wound-rotor induction. If you only had a fixed rotor resistance instead of a nice 10-stud starter, you could pull the lever on the end to throw a shorting plug into the slipring connections once up to speed. But for this application it would take longer to get up to speed on a fixed resistance and anyhow there's no-one around up here to pull the lever. The man who just hit the start button is down in the pit getting ready to begin.

 

[telectrix]

something to do with a lift or a pit cage winder?

 

[Darkwood]

Its a compressor for supplying a very large instrument?

 

[Darkwood]

Lucien is playing with us .... he posted last night made one comment and went to bed ..i waited hours of a sleepless night wondering if i was close .....:shame: Is it for the machine the wizard uses in the wizard of OZ behind the curtain???? Im right Im right YES YES!!!!

 

[GLENNSPARK]

as long as its spinning (motor) that item at the end of it wont allow cage doors to open....
similar to a washing machine motor....if its still spinning then it wont allow the door to open....

 

[Lucien Nunes]

Its a compressor for supplying a very large instrument.

Strictly speaking you should call it a blower but yes, you've nailed it again. It's a pneumatically operated rotor-resistance starter for the Discus blower of a Compton cinema organ. The stator is direct-on-line, there's a contactor nearby for that. The rotor resistance stays in circuit until the wind reservoirs have started to inflate and pressure rises towards its working level, inflating the pneumatic motor bellows inside the lower box against the weight of the two lead billets on top. The contact arm then cuts the resistance out smoothly over 8 studs.

I'm just uploading a video.