Emergency stops for LAB sockets

[infinity]

I have been tasked with installing emergency stop buttons at the doorways to a few labs, so in an emergency they can hit the stop button and it will kill the power to all the sockets in the room.

Now the problem is they are all rings with the DB's some distance away. Had they been radials t would be easy, simply break the circuit as it comes in and wire through the EMG Stop, job done, has anyone had a scenario like this and overcome it?

Would the only way be by mounting something at the DB Like a 4 pole relay, wire the ring from the MCB straight into it, and control that by an EMG Stop button sited in the circuits room, wired from the DB where the sockets are?

Or possibly catch the ring as it enters the room and mount the relay there if the legs close together, as some rooms are Dado trunking on walls.

Any advice/ help?

 

[tazz]

Run all emergency points back to the db, you know where all the rings are then, either N/C 230v or N/C low voltage, to control contactors at the db. Reason for N/C is to fail safe the system

 

[MDJ]

Obviously I can't see the set up there, when we used to wire labs we built panels for individual rooms, very simple types as well, a serel enclosure with some mcbs and dim rail plus some little plastic trunking under them and a contactor or 2 inside as well, we used to wire the ring or rings to the serel enclosure and have a start stop station with a green and red indicator lights connected to the enclosure via auxillary contacts, you could do something similar if you could find the rings going into the rooms and use then to supply the enclosure, without actually surveying the site it is all guess work, but you could make a decent job of it without switching the DB or indeed running cables that distance.

 

[Guest55]

I thought the original post said ALL THE SOCKETS are fed from the same DB if they are not the fit a new DB just for the sockets and control that one via a contactor

which is fine if the client doesnt mind every socket going dead in every lab when someone presses any 1 stop button.....................

and also assumes that all the lab circuits originate from the same db.


quite frankly , its going to be easier to convert the rings into radials so each lab only has 1 supply point to interupt.

 

[tazz]

All depends on setup.....is there an mcb for each room..?.....if there is then wire back to db....if not ring finding time

 

[MDJ]

You may find it is not that simple, the reason we used to make control panels for labs is down to rules about H&S regarding the children or staff using the room, a team leader needs to have control of the circuit locally and thats why not only a stop button installed but also control regarding a start station as well. If it were me I Would speak again to the customer regarding specific requirments. Mike

 

[infinity]

There are various rooms, some rooms have one circuit, some rooms have 2 rings, all fed from various different DB's. Switching Db's is obviously not an option as offices etc are also supplied.

If i can find the rings coming into the rooms it will be a lot easier. It does look like a tidy install not too old, all labelled up so i would expect to see a tidy install above the ceiling as well, which will also help.

 

[HandySparks]

.... and use stop button to coil on N/C contractor ...

Do you really mean this "N/C"?

If so, I suggest that the job goes elsewhere.

 

[tazz]

With offices a various dbs now in equation ....this sounds like new circuits are required
Infinity ment N/C circuit Handy sparks

 

[infinity]

N/C circuit with switch opening the circuit what's wrong with this handyspark?

The circuits in the rooms do not supply figures just the DB's do hence no switching of DB.

 

[i=p/u]

Or as biff says change to radials....

 

[ahtyrrell]

You may also want certain sockets in the room to stay on even if the E stop is pressed E.g. computers around the room or a computer and projector on the front desk

 

[HandySparks]

N/C circuit with switch opening the circuit what's wrong with this handyspark?

Nothing.

But what you said was N/C contactor, ie closed when the coil is de-energised, which for an em-stop circuit is not what's required.

 

[netblindpaul]

Work to the relevant & recognised Code Of Practice as published by the BSI, that is BS4163 and all will become clear, the requirements are spelt out in that standard, easy.

 

[not clever]

28 posts and only 2 give a descent reply
Mdj with the e stop and separate single key reset switch and blind Paul with the code of practice to go by.

 

[tazz]

28 posts and only 2 give a descent reply
Mdj with the e stop and separate single key reset switch and blind Paul with the code of practice to go by.

And your answer to multiply rooms with radials & rings mixed with offices, with numerous dbs located in different areas .....IS...?

Always one to make big comment.....without a solution.....!!!!