A part of a control system I do not understand

[hollandhvac]

This is a part of a control system I do not understand how it works. But to explain a little how it should work and see attached drawing. It is the clowded part I like to understand.

The power supply is indicated as N L1 L2 L3 and PE.

Q0 is the main breaker that needs to open when we have either fire detection of toxic gas detection, both indicated with F.D or toxic gas.

QMX is a main cuircuit breaker trigger.

How is this system intendet to work?

 

[waross]

Try the attachment again please.

Bill
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"Why not the best?"
Jimmy Carter

 

[hollandhvac]

The attachment again.

 

[xnuke]

hollandhvac,

You pretty much explained how it works. As long as QMX is shut, when either a fire or toxic gas is detected, the associated switch closes, providing a complete circuit to energize trip coil Q0 (with pins A1 and A2) with the 230 V potential difference between L1 and N which trips Q0 breaker.

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[hollandhvac]

And how should QMC close? is that through the loop around it?

 

[Skogsgurra]

QMX (can't find QMC) is probably closed by hand. The loop (ten turns, it seems) measures fault (ground) current and trips QMX via the trip mechanism (the little square) when there is a current unbalance between the two wires going through it.

Without knowing exactly what the purpose of this equipment is, it is difficult to have a well-grounded opinion. But this is my best guess.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[ScottyUK]

QMX looks like a 6A RCD with a 300mA [Δ] trip. The shunt trip for MCCB Q0 is operated by a signal from either a fire system or toxic gas. From the lack of other auxiliaries I expect that Q0 is a manually reset MCCB.


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