switchgear for lift

[russells]

Hopefully this one will be a simple one to answer.

A lift in a premises as been determined as a fire lift (to be used in evacuation under fire conditions)
the lift as to have 2 supplies of power, with basically switchgear (not provided in the lift electrics) that would simoultaneously cange the supply if one of the cables supplying was burnt out.

So this is the situation, we have a mains board in a building with plenty of spare ways in the board, and capacity, we will run two single phase supplies from this board to the lift motor room (by the way the fuseboard cupboard, and the lift motor room have enhanced fire protection) the cables have to go through different routes in the building fabric to get to the motor room (basically have a fire compartmentation drawing of the building and cabling must take different routes in different fire zones) (fire officer happy with this so).

My question is what switchgear do we have in the motoroom, we obviously have two cables from the same fuseboard that will go through a changeover switch, one cable will be master(either one) and one will be slave. the need will be for the power to not be interupted to the lift.

it is possible that we could use a manual type switch, again what would this switch be called, does this exist.

I am not an electrician but a construction manager, this problem is looming in the near future, this isnt in original building spec and will have to cop the cost our electrical contractor is going to wrap me up in smoke and mirrors and try and charge me a fortune so hopefully can gather as much information as possible.

Welcome any questions, and of course answers.

Russell

 

[trev]

Both supplies coming from the same board but taking different routes to the proposed motor room.
What happens if the fire breaks out in the location of the board?

 

[russells]

Trev

If the fire breaks out at the actual board then that will obviously cut out both supplies, however the fire zone will be identified as in the board and the evacuation plan would be not to use the lift. (there is very detailed fire strategy training for all staff)

it is a nursing home with a two storey lift in a almost remote extension, (remote being they are linked by a passageway, glazed corridor).....and before somebody points out, one cable will run internally, and one will run on the wall externally at eaves, (so as two give fire compartment seperation)

Russell

 

[spark 68]

Both supplies coming from the same board

That's what I was thinking Trev,
usually they have to come from two different DB's and usually one is a backup supply/essential supply (Generator or otherwise), this falls under safety/life support regs.

I would try and get some more information first, before deciding anything.

Some other posters on here will have more experience of these things.

 

[Des 56]

An automatic transfer switch will cost you a bomb and even then your supply is not guaranteed

Why cant they use a battery powered secondary system

 

[spark 68]

I have built the auto transfer part before, this is not a major problem,

but it is the problem of the second supply and all of the associated additional building/safety/fire regs which will be the problem

 

[johnboy6083]

Hopefully this one will be a simple one to answer.

A lift in a premises as been determined as a fire lift (to be used in evacuation under fire conditions)
the lift as to have 2 supplies of power, with basically switchgear (not provided in the lift electrics) that would simoultaneously cange the supply if one of the cables supplying was burnt out.

So this is the situation, we have a mains board in a building with plenty of spare ways in the board, and capacity, we will run two single phase supplies from this board to the lift motor room (by the way the fuseboard cupboard, and the lift motor room have enhanced fire protection) the cables have to go through different routes in the building fabric to get to the motor room (basically have a fire compartmentation drawing of the building and cabling must take different routes in different fire zones) (fire officer happy with this so).

My question is what switchgear do we have in the motoroom, we obviously have two cables from the same fuseboard that will go through a changeover switch, one cable will be master(either one) and one will be slave. the need will be for the power to not be interupted to the lift.

it is possible that we could use a manual type switch, again what would this switch be called, does this exist.

I am not an electrician but a construction manager, this problem is looming in the near future, this isnt in original building spec and will have to cop the cost our electrical contractor is going to wrap me up in smoke and mirrors and try and charge me a fortune so hopefully can gather as much information as possible.

Welcome any questions, and of course answers.

Russell

please remember your responsibilities my friend, as there was an incident recently, where a back up supply was not adequate and a young man died (his respiratory equipment stopped working), when the power failed. I beleive that the HSE will sucessfully prosecute the people responsible.

IMO the above would have been avoided, had an automatic generator been supplied to the premises in question.

If a fire causes a short circuit to any one of the cables from the same board, then it is likely that the breaker supplying that board will trip, unless your discrimination is spot on.

IMO, it is well worth exploring the possibility of a backup generator

 

[russells]

At moment fire officer is happy that both supplies will come from same dis board, both supplies need to be dedicated from mains board and this is only option anyway. (obviously we could have another power supply from our proivider....again cost!!)

(automatic transfer cost a bomb says des56,)(not sure about battery supply, )


What would you call a manual changeover switch??

 

[russells]

johnboy,

The home does have a backup generator supply, this is a manual changeover, the periodic inspection of this equipment and is fine, its not my baby anyway, i am a contractor building a new extension were the existing building as capacity to run the new extension,

the client as payed a fortune for fire consultation and this is what we have to provide, as i have said i am just trying to stay one step ahead of the costs from my electrical contractor, by being savvy about the cost and the options.
russell

 

[trev]

What about an uninterruptible power supply? expensive I know but the advantage could be that if main power fails then back up power kicks in almost immediately, no need to go looking for the guy who knows where the manual changeover switch is in the dark etc

 

[russells]

Again trev, the generator back up for the home is non of my buisness, It meets with the CQC who are the body that give them the ticket to operate the home (care Quality commision)

 

[spark 68]

My Final piece of advice Russell, is to get everything in writing and not just verbal.

I understand the 'mechanics' of changeovers etc. but Iam not clued up on the legal aspects.

 

[trev]

I reckon I know a couple of guys who can answer this one. I shall PM them for you Russell

 

[johnboy6083]

netblind paul being one of them?

 

[Specialist]

That's what I was thinking Trev,
usually they have to come from two different DB's and usually one is a backup supply/essential supply (Generator or otherwise), this falls under safety/life support regs.

Not done this sort of Install for a long time, but when we were doing them the Lift allways had 1 primary supply from the Mains & the Back up was from a Generator, switchover was allways Automatic, Never Manual.

In the event of a fire or other Emergency where power goes out but you need the Lift for evacuation you can't rely on someone remembering to go and do the switch over, possibly risking their lives in the process.

 

[trev]

netblind paul being one of them?

If he were on yes but he wernt

 

[spark 68]

The other point on this generally is, AFAIK this is not subject to 'Normal' BS7671 requirements.

 

[mogga]

Id suggest automatic change over for the generator and running second supply from genny db most backup gennys iv seen only have anuto change over BUPA Homes have a genny hookup not an onsite genny tho

 

[russells]

ok theree may be some discussion to the whole set up being not normal etc.

the question remains, what name for switchgear, name of automatic switchgear, name for manual switchgear.

I need to start looking at costs for switchgear, but do not know what to search for.

just on a note, the management of a fire situation in this home, (like many others) is a controlled evacuation, the staff have very thorough training and the whole building infrastructure, both the existing and the new have enhanced measures for ,
1. Ignition of a fire being incredibly unlikely (obviously arson is never considered in the fire equation as you just cannot build in measures.) combustible material as been risk assessed an non combustible replacements are prefered.
2. fire fighting equipment both manual estinguishers, and a sprinkler system. (fire fighting training to all staff)
3. fire alarm and zone reference panels at strategic and nursecall points.
4. mag locks, overhead automatic door closures to all bedrooms, fire compartmentation enhanced over what part B LABC determines.

The risk is taken very seriously, and managed very seriously.

Russell

 

[spark 68]

Generally when we have built this kind of switch gear, it is just called an Auto Changeover,

As several of the posters have already said, this will be located at a point where the person responsible for safety/fire/building control deems to be suitable, the supply cables taking two different routes, depending on the zoning of the building.

As I already have pointed out the PIR for this is subject to different rules than BS7671, and may fall under various different Statute laws, which I cannot advise on.

This is a complex and specialist problem on so many levels, and costs may not be a consideration for parts of this.

Netblind Paul and several other contributors on here may be able to give you a more in depth answer.