Safe way to artificially trigger a circuit breaker ?

[kiwi32]

Well,we are in for an odd question here !
The situation is very simple: I would like to remotely and artificially trigger a circuit breaker.I have a regular breaker panel,and would like to put a kind of red emergency button near the load that I could push to trigger the circuit breaker and kill the whole circuit.
I am aware that normally I would just wire the load to the switch directly and use some sort of NO relay or a special switch to make this work but it is not possible in this application since I need to be able to shut down the whole circuit.
Of course I could just short the circuit (lol) but for obvious reasons this would be crazy and unsafe.So is there any reasonable ways to do it ? I doubt so but maybe you have some tips...
Thanks,

 

[Hawk81]

Why can you not fit a relay?

 

[hoover]

Ever heard of a contactor? Fit it at the start of the circuit. Control it via a em push stop button.

 

[kiwi32]

Basically,because the wiring is in the wall and my only acess is in a wall switch.Part of the circuit is in parallel so fittinf a relay woulsd not shut down the other part.

 

[Hawk81]

Ever heard of a contactor? Fit it at the start of the circuit. Control it via a em push stop button.

A relay and contactor are the same thing

 

[kiwi32]

Whats an em push button ?

 

[Hawk81]

Whats an em push button ?

I think he means an emergency stop button

 

[kiwi32]

Oh xD But the problem is that I can't retrofit the cabling... The work is in a finished home and the 2 rooms are far appart

 

[Hawk81]

What about a wireless relay?

 

[Knobhead]

Have a look for Telemecanique auxiliary shunt trip unit. It sits along side the MCB and has a little lever that goes in to the side of the MCB.

There are other makes but I’ve not used them.

 

[grantr37]

you can get emergency shut off breakers with some extra leads coming out that go to a rail mounted trigger unit, a signal to this and it flips the breakers off just like an emergency stop, cuts off the power supply a bit like an industrial Fireman's switch..these swap out in place of the breakers already in the board......take a look at siemens and schneider electric online, and a look in RS online catalogue, will be in there....
They can be powered off by a fire alarm or by a pushbutton/BMS signal.....they are also available for fire door magnetic catch closers....
There is a unit (expensive) that connects as well that has a piezo sensor and a PCB in it that detects the high pitched noise from a fire alarm/ regular battery smoke alarms and cuts the power or closes fire doors, this is for locations without a main fire panel such as some small B&B's and Cafe's etc...

 

[kiwi32]

Thank you for your suggestions,Ill have a look tommorow and will keep you posted...

 

[grantr37]

NZM Moulded Case Circuit Breakers - Eaton Europe - Circuit Protection

 

[grantr37]

page to look at as well....

NZM Moulded Case Circuit Breakers - Eaton Europe - Circuit Protection

 

[kiwi32]

Alright,so after some reading and further research I am probably going to go go with the wireless relay route.
The controlable breakers do sound interesting but they require a wire from them to the switch which is not possible in my situation.
I chose that relay in the end: Lutron Wireless Powpak Relay Module Model RMJ 16R DV B Power Pack "New in Box" | eBay
Thanks again for all the helpful reponses !

 

[Rockingit]

All you need is a shunt trip - most of the proper brand CU manufacturers make them - 12/24VDC and 230V trigger options normally available. If you cant install cable for the trigger circuit then think about using some of the new home automation RF stuff. You can buy simple RF switches and remotes off the shelf in Maplins for next to nothing.

 

[kiwi32]

After investigating shunt trips I only see one problem.They take an extra breaker space: " shunt trips take an extra pole space for the trip ". In the case of this installation this is a huge problem since the breaker box is already full.Would you happen to know any shunt trips breaker that would fit in one slot only ?
Thanks,

 

[tazz]

You have been given some good advice so far, but every option dosn`t seem to suit you.
1. what are you actually try to shut down & why
2. Cant you used a boxed relay near to load..?

 

[Knobhead]

Kiwi, just think about what you’ve said.
With something that is safety or system critical where does one unit space come in to the equation?

It’s required and therefore necessary, budget for it in the design if needs be.

 

[Knobhead]

I’ve spent most of my life designing control systems. If I say a 4000A ACB needs a shunt trip it got fitted as requested.
No one has ever questioned me fitting safety circuits to a design.

NetBlindPaul, will give you the final say on this.
I’m good, he’s better and so I’ve PM’d him.

 

[Knobhead]

Kiwi, empty your PM in box!

 

[netblindpaul]

kiwi,
If this is a safety related issue then you need to do it correctly.
A shunt trip will do as will a contactor.
However, until we can understand what you are trying to achieve then we cannot give you the correct advice.
Is this domestic, commercial or industrial?
Is this in the UK? (Thinking about your user name and a few terms that you have used in your posts I'm not sure you are?)
The advice you have been given is sound, if this was required, why was it not originally designed into the system?

Please explain what you are trying to do & why then we can give you better advice I'm sure.

 

[Rockingit]

After investigating shunt trips I only see one problem.They take an extra breaker space: " shunt trips take an extra pole space for the trip ". In the case of this installation this is a huge problem since the breaker box is already full.Would you happen to know any shunt trips breaker that would fit in one slot only ?
Thanks,

Talking small domestic scale: a shunt trip sits next to the MCB that you want to control, normally taking up 1 or 1.5 spaces on the DIN rail. This brings in an interesting thing also about whether you are wanting to use the MCB for switching or for isolation - if the latter then you'll have to change the MCB to a DP one anyway, so that's 2 spaces for the MCB + 1/1.5 for the shunt. You'll probably find it easier to mount it all in a separate DIN rail box - Lewden make some nice ones for less than a tenner.

One thing no-one's mentioned yet also is that you can't (normally) reset a small scale shunt remotely - you have to go to the CU and reset the breakers.

 

[malcolmsanford]

Hi Rock it may not be necessary to use a double pole MCB for switching or isolation if it's a normal final circuit in a TN system, unless it's switching or isolation for dual supplies then you would.

As we have all said mate wee really need to know what he intends switching

 

[kiwi32]

Thanks for the input.Here are a few clarifications:
The setup is in a canadian home,up in the north.Basically,I have a small server farm,part in an semi-finished basement and part in a vacant space under the stairs.I estimate the combined power draw of all the servers to arround 2500 watts.The wiring and electrical installations are all domestic,although my electrical panel is 250amp instead of the regular 150amps arround here.2 regular circuits that were already in place before the server farm was put in operation provide power.1 to the basement and the other splitted between the basement and under the stairs.
Although it is not an obligatory safety measure I think it would be great to have a way to shut down the whole circuit with a button near the load.The way the wiring is done wont allow me to shut down the whole basement circuit with a single switch.Plus I do not have access to it since this part of the basement is finished.Also like I said the breaker box is already filled completely,which prevent me from using a dual-slot shunt trip.
The reason why I wanted to add this is because I had a problem with 2 connected servers last month,the power supply basically started pumping 15v instead of 12 and the servers got both smoking hot.I noticed a burning smell and saw what the problem was.I had to run to the breaker box to shut down everything and lost the 2 servers.An emergency button near the load came to my mind after this incident.
The wireless relay did sound like the best option but I do agree that shunt trips seem to be designed exactly for this kind of situation.Note I also do not need to be able to reset the breaker remotely.
Btw just cleaned my inbox.
Thanks again for your time,

 

[Knobhead]

Things become a little clearer now. If you are really pressed for room in the distribution panel then a contactor would be the way to go. Not knowing what domestic / commercial MCB’s are available in Canada does put us at a disadvantage.
I did something similar years back with my own house where there was a P/B at the side of the fire extinguisher that would kill the entire supply. Luckily it never got used in anger. (It caused anger though, I pressed it while she was watching television).