What containment would be best for this installation?

[Davisonp]

Hi,

I am trying to prepare a quote and am wondering the best way to approach this particular installation as it is not something I have experience of.
It is a church setup and I have been asked to get a switched 32 amp feed from the main distribution board to a sub distribution box in the main hall for a sound and video system, then from the distribution box, on to sockets and equipment at various points in the main hall. The main hall is used for lots of children's and toddlers activities so the installation needs to be child friendly (Eg, not using trunking where they can pull off the lid and get to the cables inside).
The question is in two parts:

Part 1) What is the best containment option for getting the power from the main distribution board to the sub board in the main hall (through several rooms and walls)? NOTE: I will have a 100mA (time delayed?) RCBO in the main distribution board, so if an RCBO in the sub distribution board trips, it will not take out the RCBO in the main distribution board.
Also, I assume the best route for the cable is up to the ceiling, then along just under the ceiling where it cannot easily go into the ceiling (it has a hung ceiling in several areas so that would be the best place for the cable).
The options for routing the cable seem to be:
a) Run SWA from the distribution board to the ceiling, then following the ceiling through the rooms and into the main hall then onwards to the switch for the Audio Video system in the main hall. This is fairly straightforward.
b) Run steel or plastic conduit between the main distribution board and the Audio Video system in the main hall. This would follow the same route as the SWA, and would I guess be a lot more work to bend and fix the conduit in place. I would use single cables for the run instead of SWA? Any opinions or experience of this method would be appreciated.
c) Run trunking (probably 16*25mm plastic trunking) out of the distribution board to the ceiling, then round to the main hall using the same route as the SWA would have used, then from entering the main hall, change into steel or plastic conduit for the rest of the run to the switch for the Audio Video system in the main hall.

Part 2) From the distribution board to the sockets and equipment at the other end of the hall, what would be the most appropriate containment with regards aesthetics and functionality? What would most people be recommending to customers? Again, it must be able to be knocked without breaking and not able to be dismantled by little fingers.
I have seen several similar sites (church halls and school halls) where steel conduit has been used and I suspect that is the way forward.
Any experience appreciated.

Best Regards

Davisonp

 

[i=p/u]

when we did a church, we used high tuff, had to lift floors to get to places down low and as you say use the beams along the high ceiling and drop down, everything was surface mounted as the wwalls were like sand and no cement..

so laser level and cleats and still watch the wall for falling apart if it is in this condition.. and maybe where you have to have accesories down low, you may want to pipe.. but....

 

[i=p/u]

and allow for a platform if you dont have one and time to move around with it...

 

[Guest123]

If you really want it to blend in, bare MI is the best option but, also most expensive both material & labour wise. Also if you dont have experience with it best not to go down this route IMO.

An SWA submain is probably the way forward, you need to clarify your protection arrangements though as there is no such thing as a 100mA TD RCBO. What earthig system is prsent, do you need additional earth fault protection at al???

For the final circuits, high impact PVC conduit wuld be ok IMO, if the chances of damage are that severe though, galv could be an option.

 

[Engineer54]

If this is a listed church, then you might want to check with the powers that be, if any stipulations have been laid down by the insurers. Most of the older churches will have stipulation clauses calling for only MICC for all LV circuitry unless otherwise agreed...

 

[johnboy6083]

I would opt for steel conduit if MICC isnt stipulated, primarily because im happy working wity conduit, it doesnt cost too much, and i would be happy that i could be competetive.

I would choose steel over plastic because of aesthetics and protection. Although platstic is far far quicker and easier to fit.
MICC (pyrotenax) would look the best by far, but its whether you would win the work because of the cost and time taken to fit it.

 

[i=p/u]

And recently I seen church heating circuit done H/R flex, penny's tight maybe

 

[Davisonp]

and allow for a platform if you dont have one and time to move around with it...

Yes, a platform would be a huge benefit, so I will include the cost in my quote. Good advice.

 

[Davisonp]

If you really want it to blend in, bare MI is the best option but, also most expensive both material & labour wise. Also if you dont have experience with it best not to go down this route IMO.

An SWA submain is probably the way forward, you need to clarify your protection arrangements though as there is no such thing as a 100mA TD RCBO. What earthig system is prsent, do you need additional earth fault protection at al???

For the final circuits, high impact PVC conduit wuld be ok IMO, if the chances of damage are that severe though, galv could be an option.

Yes, MI would be the best, but there is no way the church would spend that much on it, so it is SWA, or conduit, they also probably would not stretch to chasing in.

 

[Davisonp]

If this is a listed church, then you might want to check with the powers that be, if any stipulations have been laid down by the insurers. Most of the older churches will have stipulation clauses calling for only MICC for all LV circuitry unless otherwise agreed...

Hall and kitchen built in the 70's and a large extension with lots of rooms opened in 2000, so there are no hoops to be jumped through, it is just what is practical and ascetically pleasing.

 

[Davisonp]

I would opt for steel conduit if MICC isnt stipulated, primarily because im happy working wity conduit, it doesnt cost too much, and i would be happy that i could be competetive.

I would choose steel over plastic because of aesthetics and protection. Although platstic is far far quicker and easier to fit.
MICC (pyrotenax) would look the best by far, but its whether you would win the work because of the cost and time taken to fit it.

I am starting to think steel conduit this is the best option for this church, certainly in the main hall.

 

[Davisonp]

there is no such thing as a 100mA TD RCBO. What earthig system is prsent, do you need additional earth fault protection at al???

Yes, what I had seen is a MEM 100ma RCBO, and I had assumed other manufacturers would have the same thing available. Further investigation has reveled that what I had seen was a MEM EATON 100mA add on to an existing MEM MCB to make it an RCBO, and only available on Ebay, so I will not be using that.
I guess I will have to put a Wylex 100A 100mA Time Delayed RCD in it's own enclosure near the main distribution board.
The earthing is TN-S (I have been told).
I have not had chance to investigate the building as an electrician yet, (attended a wedding a while ago, but not looking at the building then), but I want to have a good idea of what is required before I take a look at the building.

The sub main does not need to be RCD protected by regulation as it is going to be surface mounted, but the client (sound system installer) has asked for an extra RCD on the sub main. I will suggest that they do not need one and see what they say.