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Unidentified component help

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Mnik1

New Member
Hello. I'm trying to detect and fix boards of old turret lathe and components are from ~70's or so, made in west germany. I need help detecting this two components which i dont know exacly what they are and how to test them. This big component with metal protection (underneath is coil and inside is some kind of glas, 5-6 outs to pcb) and red component (i suppose its kind of varistor?) with 150/4 writen on it. Anyone have an idea what this is? Thanx
 

fezder

Well-Known Member
Do you mean those metal thingies that are labeled t1 / t2 and 1 /2? To my eye they seem to be sort of transformers, and those red ones, yeah, probadly varistors, but hard to say without any markings.
As for testing them, transformers either short inside or snap cut (so short circuit or open circuit) and hard to test without knowing values they were made. Varistors fail rarely in my understanding, they work when needed for protection. Others please correct me, but at least if they show short circuit with multimeter, they're toast, but at least they look ok to me.
edit. saw you mentioned about varistor markings, my bad

150/4 sounds like capacitor marking more, but no idea what that 4 means, or 150 in this matter....
 

Mnik1

New Member
Thanx! Here is another picture, without cover. I checked diodes,resistor,caps,etc so far and everything is fine. Is it posible that this big component(transformer as u said) is fried or it is last to suspect? I have 4-5 boards of this machine, and there is probably ~8-10 of this components
 

fezder

Well-Known Member
What are symptoms (fault, what it should do, what it does)? dWhat equipment you have? (oscilloscope etc...) I personally don't suspect transformer, at least yet.
Also, that transformer looks like also, possible solenoid/relay? What is at the ends, like inside in that tube?
 

Mnik1

New Member
I just find out, its probably a reed relay. Looks similar to https://standexelectronics.com/wp-content/uploads/HI.png
I have basic equipement, as my basic knowledge. There is two problems with machine. Old problem,which is not that big deal; when i turn on main switch, motor of machine turn on by itself randomly witout pressing motor power switch. It does sometimes in a min or so and sometimes instntly. So 'something' randomly power a 24v relay which turn on motor idle state. New problem is big one, electromagnet which clamp gears used for moving revolver head wont work, that happend after failure of push switch which cracked, and when is substituted with similar push switch (NO+NC) it is not working. If i connect electro magnet clamp direcly, it works and after ~5sec or so, 6amp push-in fuse goes down. Thanx for help!
 

fezder

Well-Known Member
DUH! How I forgot reed relay...
So 'something' randomly power a 24v relay which turn on motor idle state
So, without pressing power button, something inside bypasses power button? Can you post photos where this power button is seen? Either way, depending on circuit, relay's coil is connected to either ground or vcc. If this appliance is in metal enclosure, this can be due short to casing which turns on relay (thinking out loud)

electromagnet which clamp gears used for moving revolver head wont work, that happend after failure of push switch which cracked, and when is substituted with similar push switch (NO+NC) it is not working. If i connect electro magnet clamp direcly, it works and after ~5sec or so, 6amp push-in fuse goes down
Does it trip the fuse after ~5 secs? That doesn't sound good if fuse blows, never is good thing.
what sort is this electromagnet that clamps gears? can you post photo of it too?
 

fezder

Well-Known Member
It does sometimes in a min or so and sometimes instntly
This sounds like bad contact, annoying. Or cracked track (or both.....). When troubleshooting this scenario, how I start, is tapping around pcb to get general idea where crack is. Also, heatgun and/or freeze spray can give these places away (bad contact doesn't contract/expand how it should and causes off behaviour) and finally, re-solder any and all suspicious looking solders. Since it's 70's apparatus, it could be bad solder joint.
 

fezder

Well-Known Member
If there are electrolytics, they're pretty much good to replaced as well as paper capacitors (old caps can cause leakage and ESR rises to clouds, but ESR is more concern in modern stuff) IF you give it shot with heatgun, don't blow hot air directly to these caps, they can pop.....gentle heating is enough, but with freeze-spray you can blast quite willingly.
 

RODALCO

Well-Known Member
That is a reed switch / with operating coil.
The switch is a glass tube with 2 contacts in it which close when a magnetic field is present.
If you hold a magnet near the reed switch it should close.
These reed switches are also often used as door switches, in alarm systems.
These switches are only rated for a few mA's at the most.
 

RODALCO

Well-Known Member
Red discs are M O V 's I think,
Metal Oxide Varistors
150 Volts clamping and 4 kA.
 

RODALCO

Well-Known Member
WIN_20160607_214357.JPG Couple of reed switches and a coil I found in my workshop.
 

fezder

Well-Known Member
Reed reminds me of mr.Reed from movie "liar liar" where jim carrey acts as lawyer that is forced for a while to tell the truth. :D
 

cowboybob

Well-Known Member
Most Helpful Member
Odd that it has four terminals:
upload_2016-6-7_7-3-50.png
A SPDT reed switch? Or maybe a bipolar CT (is there such a thing?)?
 

RODALCO

Well-Known Member
Two for the coil and two for the reed switch?
Don't think so, that coil may have two windings maybe two imput sources.
The reed switch gets normally soldered at the end tails of the glass tube.
See picture in post 4.
 
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