installing a lighting bar in a school hall

[RF Lighting]

Ha ha sounds about right!

I have had a similar problem in a local community centre with an asbestos ceiling. It was council owned, and they wouldn't even allow us to install wall fixings in the building until the asbestos was removed.

 

[andrew1210]

The answer was "it's fine the other two fixings are ok" ok, we'll worry over the safety chains/bonds, but who cares about the actual bar. I wasn't bothered, the desk was on a 20m extension cable so I could sit up the back of the hall, so it wouldn't bother me if it fell [/selfish]

 

[SUNRAY]

Thats as maybe but try using chains in public theatres and see how many stop you, even if safety rated and tagged

how many whats? theatre managers or council inspectors?

The man with the clipboard who signs the piece of paper which lets the show go on. He may be the theatre manager, the council inspector, the fire officer, the caretaker or uncle tom cobbley depending on the name of the council or county

how do you go about rating and tagging an old stock of safety chains?

ER??
In the same way that one would get anything tested....
By taking them to an appropriately qualified person or company.
In our case we use HSS lift & shift or Southern Lifting Services, other lifting companies may exist

 

[SUNRAY]

Well a mac is about 22kg dead weight, so you really ought to be using a 50kg safety bond. I wouldn't expect to find a 50kg bond on a 5kg parcan.

It's unlikely that a hook clamp on a parcan will go wrong, but you never know. As it's a single fixing point above peoples heads, it must also have a safety.

We only have 65Kg and 95Kg, theres no point in buying in smaller ones.

The issue with something like a parcan is vibration and nuts coming undone.

 

[Hager]

HI,

What are these LED fittings? I've never heard LEDs that can pull this much at all 6. The highest LED cans i heard of are the MTC fittings even they old pull 150w at full power.

With the bars you need to make sure that they are propley secrued to the wall/ceiling using RAWL bolts or the eqiv.

Jake

 

[timbim]

What are these LED fittings? I've never heard LEDs that can pull this much at all 6. The highest LED cans i heard of are the MTC fittings even they old pull 150w at full power.

Pulsar Chromaflood 200's pull 200W!

 

[ban-all-sheds]

How are they cooled?

Do they have a 100% duty cycle?

 

[timbim]

How are they cooled?

Do they have a 100% duty cycle?

By using the back of the case as a massive heat sink. Puts out 66W as useful light.

I've no idea how they're dimmed, whether it's PWM of FET controlled current. What I do know is that they're bloody impressive lights.

 

[dhutch]

they might be LED lights now, but anything might be plugged in later, bought or hired for events.

I very much agree with this.

Ive worked in too many small halls and schools that have bought some of this "wonderful" LED stuff, only to find out it is near useless at actually lighting anything. not to mention cheaper LEDs give a nasty "white" and are very hard to get people to be lit nicely without looking ill without using some sort of conventional fixture.

And also this.

Ive not worked in a theatrical enviroment but have done a number years as a lighting and rigging technition at a large students union while studying there and although LED fixtures where becoming increaingly common (we swapped 30 of our Martin pro400's house lights for them for instance) they are a long way from replacing conventional and hid fixtures out right. Certainly for lighting the faces of acts it was all conventional fixtures. Cant beat a set of Source 4's!

Eitherway, spuring anything like that of a ring main doesnt sound at all sensable, if only from the point of view of robust design. You dont knoe what else might be run of the ring main at the same time, and you dont want a nuisance (or other) trip on the ring main taking out your lighting. I will never forget the passionate telling off one of our newer crew got for suggesting you could run the lighting desk of the house ring main rather than one of the lighting supplies. Nothing worse than having you desk go down with 20kW of fixtures lamped on!

I presume they are cabled up with 16amp cee-form connectors?

Daniel

 

[SUNRAY]

We have installed a number of this sort of thing:
View media item 42087with a 16A feed on or near lighting bars in schools and small halls, usually for their existing 500W fittings like strand pattern23's etc. No matter how big the sign is that states a maximum total load of 4KW there are always the hirers who come in and hang 8 1KW fittings then start phoning to say there's something wrong with the dimmers.

I have also seen 6 of them wired onto the existing ring, by a local authorityapproved electrical contractor, which covered the adjacent computer room, staff room and the hall. We were called in to quote to upgrade the dimmers because they kept tripping the 30A MCB. 2 other contractors had already quoted and there was surprise when we refused to wire to the existing supply.
Instead we got the job to rewire to spare ways in the DB [3 or 4 of the 6 spurs were long enough to reroute to the DB] and while doing so also made the computer room into its own ring.
Funny how the 'faulty packs' are still there 3 or 4 years on.

My advice is to never install stage lighting onto any sort of ring circuit, unless its specifically & exclusively provided for it.

edit to correct spellings

 

[Spark123]

Do you find they blow the triac when the lamp blows Sunray? I haven't used that brand, the cheap ones (Soundlab) are notorious for popping them.

 

[SUNRAY]

Do you find they blow the triac when the lamp blows Sunray? I haven't used that brand, the cheap ones (Soundlab) are notorious for popping them.

No not that I am aware of yet, we spoke to a number of schools to find out what was in use and their reliability before we started fitting them, we do change the fuses to 4A QB.
We also have about a dozen for portable/hire stock, the only one of ours that has failed so far was due to water.
There are several brands that ppear to be the same, most of ours are Pulse I think, we refer to them as 'little 4 pack' and also have some 2 channel. As they are small, theyre easy todisguise behind a curtain or plant pot on temp installs
We seem to have standardised on these and Anytronic contractor packs for the bigger jobs.

 

[SimonH2]

Eitherway, spuring anything like that of a ring main doesnt sound at all sensable, if only from the point of view of robust design. You dont knoe what else might be run of the ring main at the same time, and you dont want a nuisance (or other) trip on the ring main taking out your lighting.

Seen that at a MeatLoaf2 gig in the local hall. Part way through, it all went dark and quiet - they had to reset, wait for the computer to boot up, and then fast forward the (digital) slides on the projector


This thread brings back memories - I was involved with "technical" at 6th form, but only in the second year as they hadn't actually built all the college in my first year ! But it did mean we had all new stuff, even if not many lights - in fact I think we had as many dimmer channels as actual lights - 2x6way Furse dimmer units with a 12 way, two preset desk on cables fitted with (IIRC) 15 way D connectors which meant we could sit outside the control room for rehearsals.

We did have a couple of problems though. The first was a lack of licence - the fire people refused a licence as the seating was too steep After some negotiations, they agreed it would be OK with grab handles on the ends of each "desk" (the seats had a horizontal "desk" about 9" wide so students would have somewhere for books, notes etc when used for educational activities.
The second was how to access the lighting bar above the banked seating. The first time involved planks from the seating to the scaffold tower, and step ladders on the planks They later figures how to build the scaf tower with unequal legs.

But I digress ...

One use the theatre got was by a travelling company. As they were travelling, they preferred to use their own lighting - an old "reostat" dimmer with the big old handles to slide up and down, and keeps your tea warm when sat on top. Wired to 2 13A plugs and with the lighting designed to avoid exceeding 13A on either group of lights. The guy did say he'd empirically found out you can normally run 16A all night, but if you do blow a fuse it can take a while before the plug is cool enough to handle
We didn't have any other supply to offer - our dimmers were hard-wired.

Best memory of all though was one March - on the 31st. A student band got permission to use the hall for a gig, and only got permission to use the stage lighting on condition they weren't flashing the lights and stuff like that - I did the lights. There'd been some discussions a while earlier, and at great expense they'd bought spare bulbs for the lights - given the price, they didn't want to blow any.
Next day (worked out the date ?) I went into a physics lesson, and mentioned to the physics teacher (in charge of technical matters for the hall) that we'd blown one of those expensive bulbs. He wasn't best pleased until he realised "e'd been 'ad" But then i t backfired, he went to the staffroom at breaktime and told the head of English that we'd blown two lamps - she was livid until she realised the date, but I got the blame

 

[SUNRAY]

The guy did say he'd empirically found out you can normally run 16A all night,

Quite right they will as long a one does not try switching 4KW on all in one go.

but if you do blow a fuse it can take a while before the plug is cool enough to handle

This is also true when running at 13A!

At one time, and for a short period of time at that, 13A unfused plugs were available under special license for each plug which specifically stated it had to be followed by a 13A fuse or 2 pole 16A type B mcb within 1 metre, 2.5mm2 minimum cable.