Magnetic CB trip circuit 1

[buzzp]

I trying to make heads or tails of a simple trip circuit. I have not seen a circuit such as this but they tell me the wiring is correct as shown in the drawing. Sorry for the crudeness of the drawing.
If the contact below the breaker closes, it trips the breaker. I am totally missing something if this is how it is actually wired. Sure the polarity reverses but at the same time, there is not potential difference across the breaker to develop a current. What is the theory of operation of this circuit? I am probably having a major brain malfunction as it has been a long couple weeks.

 

[waross]

A shunt trip?
A small solenoid inside the breaker that mechanically trips the breaker?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[itsmoked]

You're killing us here Buzz. Just post the thing directly.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[itsmoked]

That's nonsense. You're correct, something is fishy/wrong.

The drawing is entirely missing a shunt-trip that is mechanically tripping the breaker from next to it, as Bill suggests, or that's not a contact it's an idiot-light that only lights once the breaker opens and specifically it's a neon idiot-light.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[buzzp]

Problem solved. The contact is closed when everything is ok, not opened. Obviously, this allows next to no current flow through the breaker. If there is an issue, the contact opens, diverting most of the current through the breaker causing it to trip. To top it all all off, it is totally unnecessary...the breaker has some aux contacts, which are then placed in series with a trip circuit. I am not sure why they didn't just use the contact that is shown in my drawing in the trip circuit...(if it is not an adequately rated contact, then use an aux relay). Goofiest thing I have ever seen...
Thanks all and sorry for the drawing link and the later than I like reply.

 

[itsmoked]

Amazingly Rube-Golberg.

Thanks for getting back.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[buzzp]

Yes it is Keith! Thanks

 

[waross]

1000 Ohm at 120 Volts? That's 0.12 Amps.
It will take a very long time to trip a 0.125 Amp breaker.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[itsmoked]

Yep. More like a temp sensor then. If the breaker reaches 120F it trips.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[buzzp]

Sorry, forget to mention it is a variable resistor and is set at something lower than 1k. This is an explosion proof box and I didn't want to remove 30 plus bolts to measure it.

 

[itsmoked]

The bolts are nothing it's lifting the %$(@% lid.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[waross]

Reminds me of opening an explosion proof breaker panel.
3/4" bolt heads.
Just crack each bolt loose.
Then drop a 1/2" bolt backwards into a 3/4" socket so that the shank protrudes out of the back of the socket and the bolt head is deep inside the socket.
Chuck the bolt shank in a 1/2" battery drill and spin away.
No time at all.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[ScottyUK]

Be cautious if using a power tool to wind cover bolts out on stainless steel or aluminium enclosures, the threads can easily gall and - under our rules at least - field repairs aren't allowed on flameproof (explosion-proof) equipment. At the very least keep the speed right down.

 

[waross]

Hi Scotty. Let me take advantage of your information to add:
Anyone who doesn't lubricate stainless or aluminum threads will eventually gall the threads. Guaranteed.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[buzzp]

Yeah, I don't need to know the R that bad. I know its smaller than 1k and that is enough for me. I can imagine the look on my Super's face when I ask him to shutdown production and bring the box outside for measuring the R - not going to happen.
Our's is not a lid but a vertical cover - making it even funner to remove.