dje

DV247 are EU now? ! That's news to me, I remember when they were on Acton High Street as Digital Village.

 

AFAIK they are a UK-based, but German-owned company, so who knows? As for DV in Acton; my recollection is very young, very willing, but very slow (I haven't used them since they closed the branches).

As a music student in London, I used them a lot. Their prices tended to be better than Sound Control in the basement of Virgin Megastore on Oxford Street, or Turnkey on the end of Denmark Street.

It almost seems mad now that there was actually a time when you could put a multi-storey home studio equipment store on a high street in Central London and be commercially viable.

DV247 (not always quite so obviously EU).

DV247 are EU now?! That's news to me, I remember when they were on Acton High Street as Digital Village.

Has anyone sussed this out yet or is everyone as confused as me?

Like somebody else said, Boris has no idea what he's agreed to so there's not much chance of anyone else getting it.

I'd be thinking laterally about the problem - if specifically focusing a basic frontwash for one-nighters is the issue, could a second set of S4s be rigged on another bar and left permenantly in that focus? Perhaps a simple deadhung bar nearby, leaving the current bar for a 'focusable' set of fixtures. Or turning the existing bar into a ladder by atttaching another bar below the fixtures - top level is a fixed frontwash, bottom level is for focusing. Without knowing the full context of course difficult to say but don't be afraid to explore this sort of thing too as well as buying new toys! :)

That's absolutely my thinking too.

If the problem is "our FOH bar is tricky to focus"... there are many solutions. Moving head profiles probably being one of the costlier ways, with a range of other inherent drawbacks as we've both alluded to.

You are really trying to replace apples with oranges (and both costlier and inferior oranges at that), on the sole merit that you can't peel the apple by hand. It would probably be better and cheaper to buy an apple peeler.

I think every small theatre thinks they're waiting for the cost of moving head profiles to come down to a level where they never have to climb their ladder or tallescope again. The reality is seldom so simple.

I have to say that I have never found a cheap moving head profile with beam shaping, that doesn't suck.

Motorised framing shutters are just notorious for maintenance issues. Anyone who ever had to tour VL1000s will not dispute this. In the big name, big fixtures it's been addressed in more recent fixtures. But the technology hasn't really made it down to the affordable stuff yet. The cheapest moving head profiles I can think of are probably the Elation Fuze and the Chauvet Maverick Mk2. The former seems to retail at around £4k and the latter around £6k. In the used market, you might find something cheaper... but size is liable to be an issue. Shutters are mostly found on bigger fixtures, which then start to affect you in terms of the weight (which you say is an issue), but in a small venue the fan noise could also be problematic.

I seriously want to say to you that I would suggest looking for better ways to access the FOH bar, than trying to find a cost-effective moving head profile. Whilst yes you could probably have 4 or 6 doing the work of 12 conventionals... the cost is still going to be high, whichever way you do it.

Or of course you sacrifice beam shaping, and in the cheaper stuff potentially sacrifice colour temperature correction too (relying on RGBW "CTO" is mostly OK for the naked eye, less so for cameras, if that's an issue for you). But there's going to be a serious hit on aesthetics if you take away your beam shaping capabilities.

I've worked with so so many venues who've romanticised about replacing FOH focusses with moving heads. Every attempt has failed and either culled the idea once they saw the quotes, or they've gone for it and in no time they've gone back to their conventionals and rigged the movers over the stage. Even in relatively high budget venues who could afford decent stock.

What sort of size is this venue? Basically your cheapest and most effective option is going to be buying better access, I would think. Whether that's just a decent zarges or zip-up tower, or something more elaborate like beefing up the FOH points and installing a catwalk or crawl truss.

Or another option could be to consider pole op Source 4 bodies (and keep your lenses). That could be a good middle ground, removing the need to get up high but coming in much cheaper than movers. You could continue to use ladder/tower for gel and lamp changes, or even look at moving over to pantographs.

Working on a VHF "hilltop" radio site many years ago. Identified equipment fault and required a couple of transistors.

 

As the site was at top of town centre block of flats, quick trip down in lift and round corner to Tandy, (remember them ?)sourced replacements at the premium price.

 

When I put in receipt for £2 against expenses was asked why I did not drive a 50 mile round trip to the nearest detachment to get them from local stores.

I experienced a dead safety relay about 2 years ago on a job in Glasgow, the nearest place I could find with a workable part in stock was RS in Manchester.

Had them put it in a minicab, which ended up costing about 4 times what the part cost.

It appears that 10k Used is what used to be called Gearsource.

I can't say that I had a 'bad' experience with Gearsource. But they were just a bit notorious in that their website contained listings from other brokers and thus just about every piece of used equipment in the world was listed, irrespective of whether there was a cat in hells chance of being able to buy it. Gearsource would list it on behalf of a broker in America who'd list it on behalf of a broker in Germany who'd list it on behalf of a broker in Outer Mongolia who were listing it on behalf of a Hong Kong-based lighting company that sold it 15 years ago and just didn't tell anyone.

Perhaps they're trying to make a better effort of it this time, so I wouldn't dismiss them. They have a UK mailing address on their website, memberships with PLASA, the PSA and ABTT... it all looks relatively credible!

I have been receiving e-mail messages from Maplin recently - so it seems as though the Company is back!

They seem to be selling the same sort of stuff (toys?) - as when they were last around, but on purely a web based set up.

There were occasions when you needed a Neutrik XLR urgently, for example - and could get one from the store, despite it being priced at double that of your usual supplier. So they won't now have that advantage as they are mail order, so I wonder what their new niche actually is?

Perhaps you underestimate the number of people who find themselves at a loose end and need to source a crap karaoke machine, an overpriced Neutrik XLR and a cheap remote control helicopter and want to save on shipping?

I am not being funny but for long term outdoor structures I think this is where you could absolutely justify speaking to a proper video wall integrator, somebody like Creative Technologies, or ADI would be a great start

Although to be fair, with the nature of this as a permanent outdoor video display, it might be something actually better put to an LED billboard company rather than a concert/theatrical video company - the former will have a lot more experience with permanent outdoor video displays.

It's hard to say whether an IP rating directly gives an insight into long-term moisture penetration. The first number relates to dust ingress, the second of water (but not necessarily moisture) ingress. That second number is scaled from 1 (resistant to water falling onto it from above) through to 9 (waterproof when deep under water). But nowhere in the range explicitly indicates resistance to airborne moisture as you will get when leaving something outdoors long-term. So whilst it goes with the logic that a higher IP rating will probably keep out said moisture long term, the rating itself is not necessarily actually a formal 'guaranteed' measure of it. There's also the fact that with IP testing, clean water is used and as you've alluded to, sea air is a different beast and salt corrosion can be as much of a problem as the moisture itself... and indeed, the IP rating of something can change after several years of coarse salty sea air brushing against it 24/7...

I don't really understand this mentality that students shouldn't learn on proper equipment... that they should learn on some POS toy controller first and then maybe be let loose on a Strand 520 to struggle through like the old and bold had to... then maybe they can be allowed to touch a touch screen.

Why?

Frankly, the young people of today are able to grasp technology quickly. They've grown up navigating touch screen menus and using the help screen rather than the manual. The architecture of an EOS is actually likely to be reasonably well at home. Whether they can relate the technical functions to real-world purpose will come down to the quality of instruction, not the particular hardware you associate them with.

Do you think that when young people go to learn IT, they make them work in Windows 95 or MS-DOS for the first 6 months before allowing them on Windows 10? Or maybe young people who do a bricklaying apprenticeship have to mix the mortar by hand for the first 6 months before they're allowed to use a cement mixer?

Just let them on the EOS and the Yamaha. It's fine. They're not going to break anything. And you'll find that in no time, half of them will be far more astute on those platforms than you are and you'll be asking them for help.

Playing devil's advocate - Chamsys actually brought out MagicQ and the wings, before they brought out their first consoles.

So arguably, MagicQ is software designed for computers that was adapted to consoles.

MA2 and MA3 were also developed with Windows integration so much in mind that arguably it is no more 'designed for console' than it is designed for PC. It's designed as a total system architecture.

You can configure an MA2/3 showfile in such a way that there is no real relevance to control hardware at all. I'd argue that MA2/3 software is designed as software, and the user adapts it to his/her surfaces.

The point I'm getting with the MA in particular (as of course MagicQ is still clearly based on a hardware perspective) is that I can't think of any benefit of a software-only system that you couldn't make an MA system function identically to.

It's not an 8-way (these are 6, 12 or 18), but for IEC rack panels, Here you go:

https://www.pennelco...719/m-6393.aspx

Penn Elcom is always the first place to look for 19-inch rack anything.

I think I know where JM is comng from.I find that in schools and probably more so in AmDram the transportation/storage facilities are not the rather lovely flight cases used by touring companies.

In schools the storage is so often shared with sports kit, music department, etc. I've even seen stage lights in the grounds maintenance hut amoungst the lawn mowers forks, brooms & line marking machines etc. So often plugs get pinched, hook clamps take up too much space and get removed and so on.

By the time kit is used again the teacher responsable for putting it away has moved on to another job and no one has a clue that he found space in the boiler room and no one thinks to ask the caretaker [or whoever has responsibility for the boilers] who keeps tripping over them.

The box of colour frames and gels never does resurface etc.

 

I do understand where JM was coming from too - and you - but firstly, cedd made no mention of this being a school or AmDram society; and secondly, my whole point was that if you build the install like you'd prep a tour (whatever that entails for your needs) then removing and re-installing shouldn't be an issue.

Kit doesn't have to be in flight cases to be safe and organised. There's all sorts of options for carts, stillages, boxes, meat racks or whatever.

The main point is that it's thought about, that's all. Where do we store it (without needing to remove hook clamps)? How do we keep it safe? How do we ensure things are plugged back in the same place?

You don't need to admit defeat and leave kit in the air, just because some other people couldn't organise themselves well enough (whether their own poor drills, or poor decisions further up etc) to keep their gear in order when it's in storage.

It's not just touring either - a lot of corporate event venues keep their own equipment in stock, but the venues need to be available without kit, too. It just takes some thought and planning. Theatres too, need to remove things when receiving tours. All sorts.

Eventual goal is for it to have the feel of an old theatre (clam shell footlights etc.). In this mode the trusses would seem out of place, and we feel we can get suitable lighting cover from the kit hidden by the prosc and some period luminaires that are awaiting an overhaul (possible led conversion within the original shell).

There would be a wedding season so it's and out's wouldn't be too often, and we may even have the space under the stage front to leave the truss assembled and rigged if we can create a trolley for it.

I'd suggest that as a good plan. At 6m, fabricating a trolley that one or even both trusses could land on - with fixtures remaining rigged (depending on how high your stage is) should be doable! A nice neat solution right there.

As a thought for you - when it comes to 'hiding' the safety steels we talked about, one thing that has worked in other places is to hang chandeliers on the end of them. If you leave the short soca tail in as I said about, you can use one circuit of that to run the chandelier, too. That might fit nicely with your aesthetic.

The on stage truss plan includes an upstage and downstage truss running across the stage, with a central truss running to front to back (with the same at the stage left and right ends) so we have 3 good pick up points. These will pick up ladder truss which will either be rigged as LX or will carry curtain tracks.

That seems reasonable, but it's quite a lot of truss. If you could do the two long trusses running the full length of the venue (as per the previous post), then providing the roof beams are good for the load, this could well give you all the over-stage support you need for a much lower cost.

It seems silly to build a freestanding ground support if the building has a load bearing roof, no?

Disclaimer - all advice below is given 'in principle' with the usual caveat that any engineering decisions should be made on the professional advice of a suitably qualified engineer.

The freestanding (ish) truss is the most expensive bit, and will probably come later. It prevents having to deal with the troublesome roof structure above the stage though. Once you're upstage of the pros the ceiling vanishes and the roof just goes straight up to the apex. The joists we'd be attaching to above the house continue through to above the stage, but they are too close together to fly a truss/bar/whatever of a useful length on stage. Out front of house the trusses will be 6m long, with points 4m apart (spacing of the joists). I'm happy with a 1m cantilever given it's replicated on both ends and will only be LX stuff. I may stick a "no more than xyz" on the cantilever, but don't think we're anywhere near making the bar unstable (calcs to be done!).

Above the stage though we need nearer 10m trusses/bars/whatever as the pros is 8m wide and if a show uses a few cloths we'll need stacking space (wipe tracks - no height for full flying). Putting a few cloths on the end of a 3m cantilever (given 4m apart pick up points) is starting to sound far more silly!

A freestanding mother truss with roped bars flown from it fulfills all their needs (they're never going to be able to fly higher than pros height as the roof apex begins almost straight away).

Well the good news is that your 4m spacing in a 6m truss is more or less textbook (providing the truss loading is uniformly distributed) so don't worry about your FOH trusses too much, it sounds like those beams are already in a good place.

In principle the freestanding ground support makes absolute sense - especially if at the U/S end you can utilise the wall for support rather than needing truss towers.

BUT - of course you don't want to be hanging a 10m bar / truss from the far ends. For a 10m bar on 2 points, I'd recommend a point spacing of approx 6.5 to 7m. So with an 8m pros, that means either (a) having your truss towers in view (which I presume you don't want!!) or having to put some additional truss in this ground support to support your (presumably) sub-hung bars.

I wouldn't say using the roof joists is out of the question - you could attach a truss directly to the beams to take the weight, and sub-hang your bar below.

If the beams are good for the weight, then your truss* (see below) would likely be fine providing that it itself is suitably rated for the cantilever load and the deflection is suitable for your purposes.

I say truss*, because it may be that you can do it with steel or aluminium section fabricated into a custom 'rigging beam' by a suitable engineering company.

Cable routes are currently flexible. As much of the LX install is reasonably temporary it'll be socapexes to each truss. We have a route through the roof but won't go that way unless the flying method means we have to make it safe to get up there often. Instead we're considering some form of trough running down the side of the house, suitably decorated to not stick out like a sore thumb. This would be at roughly bar height. It'd be a trip up zarges to let out enough soca to drop a bar in, and then the reverse once they're out.

Sounds reasonable. Alternatively, you could drop socas down from the same hole as the rigging point and secondary, which stay at that set length... then when lowering the truss in, add extensions in which can be removed once the truss is back at height. Might be neater, and you can share one set of soca extensions between all your trusses to save some cost.

I'd probably construct some form of shroud to go around the hoists that attached to the top of the truss (an open topped/bottomed box) so they weren't so obviously bright yellow!

Alternatively, how about a fabric 'jacket' with a velcro or zip enclosure which could be applied to the hoist once fixed in position, and removed before lowering? Then there's no need to worry about anything getting caught in the mechanism.

Painting them isn't completely out of the question (as long as you keep the paint away from the moving and load-bearing parts), but you may want to check with the manufacturer for explicit written permission (bum covering).

An alternative we'd considered to fixing points to the existing joists was to lay a pair of 40cm square trusses up in the loft space. A pair of 15m long trusses laid across the 5m spaced roof structure tie beams would get from the upstage wall (resin bolted in), across the stage and then through above the ceiling above the house. If a structural engineer would sign off the load per bay then the truss spec could be used to allow fixing points wherever we need, including future plans we don't yet know of. It'd just need a neat trapdoor style hole cutting in the ceiling.

The tie beams won't be perfect so the truss would need shimming to ensure it was in contact with all of them nicely. Is this something that is done often? I consider myself competent in the basics of theatre rigging, but establishing the points is very different (and won't be completed by me). It's helpful though to understand what we're asking for and in deciding which avenues to pursue when writing a spec and speaking with contractors.

To confirm, are you suggesting 2 beams running the full length of the room from the US wall, to the far rear-of-auditorium wall (or, at least as far as the furthest D/S points would need to be)?

If yes, then IMO this is a strong idea. You could space them at the ideal spacing (for your stage trusses I'd say that's circa 6.5-7m). For your FOH bars, you could still go to the roof beams as previously discussed, or alternatively you could lay a truss spreader over these 2 up-downstage beams.

To answer your question... yes, laying trusses atop of roof beams is relatively common practice. Often referred to as 'spreaders' or the Americans say 'spanners' (because 'spanners' are 'wrenches' )

Shimming them is indeed the responsible thing to do. You'll likely secure the truss at each point where it crosses a roof beam anyway so the shim can be inserted and the truss secured down to the shim so there's no movement.

I once did an install with a 50m long rolling beam track secured below the beams in the roof. The installer didn't shim or adjust them for variance in the exact beam heights. When the show came out several years later, the trusses were permanently warped.

This is all something I could help you with (professionally) if you want to drop me a PM.

Taking kit out usually leads to damaged kit and damaged venue, plus something always goes missing.

Whilst in a slightly different context... touring shows manage to take kit out of venues night after night and put it all into new venues without losing or damaging any kit or the venue...

So de-rigging stuff doesn't have to mean damage or loss, does it? For me it's a case of designing the install to be demountable - designing it almost like a touring system in effect.

Plenty of venues have done this successfully, with kit kept in cases / transport dollies etc, cable looms built and labelled, etc etc - as you would for a tour.

Just needs a bit of thinking about, up front.

It kinda depends on budget doesn't it. Can you give any indication of what kind of money you're talking?

For the stage, your idea sounds relatively sensible. Truss structure into the floor at one end and into the wall at the other with some Hilti anchors, you'll be fine (subject to competent contractor etc etc usual)

For the FOH...

Well option 1, to answer your question... the Yale 360 chain hoist can be operated inverted. https://www.liftings...-hoist-209.html . That said, they're unlikely to meet the appropriate standard to be 'approved' for suspension over the audience without a secondary.

But is that a huge issue? If you're going up to pack the chain into a bag anyway, you could leave a pair of steels or chains hanging out of the roof with a shackle or latch hook on the end, to go into an eyebolt bracket on the truss. It's barely any extra work.

For electric chain hoists... you kinda get what you pay for. I'd personally steer clear of the scaffold type, they're designed for short term suspension and local control (ie use of a pendant stood next to it, not from a motor controller).

If you could opt for a D8+ or BS-7906 Cat A (now superseded by EN17206) compliant electric chain hoist, you could suspend the load on the motors all the time and not need access to the roof for removing steels etc - so it's a good thing for work at height etc.

Another option could be winches. With diverters in the roof, you could run the winch lines through the roof space back to a sensible place for the winch to live. Electric winch - that could be in the roof space, hand winch could possibly be on stage.

You could go with an electric winch or a manual winch could be a tad cheaper, particularly as you wouldn't need to budget for a controller (winch controllers tend to be dearer than chain hoist controllers). Some manual winches permit use of a cordless drill to turn rather than a handle.

On the cost front, the perk of winches is that you only need one machine, irrespective of how many lifting points. The downside is that winches - even hand winches - can be rather costly (1 winch + rope + control is likely to be similar cost to 2x Electric chain hoist + control, but cheaper than 4 hoists + control, if you'd be happy with always having to bring both bars in at once).

As a question for you - what's your plan regarding cable management FOH? If you want to get fancy you could do an IGUS energy chain, or perhaps flip-flop cable trays from the roof, a lot neater than a swag of cable. Otherwise you may also need a plan to hide your excess cable once you've raised the truss.

With electric chain hoists, you could potentially do chain runners from the roof.

Active Lamp Timer is when you try to strike the fixture within x-time of lamping off.

It can also occur if after y-time of attempting to strike the lamp, it still hasn't struck.

Troubleshooting:

1. As indyld says, turn off the lamp strike sensor (as this disables the error)

2. Now try. Does it strike the lamp?

YES: Problem with the lamp strike sensor or firmware

NO: Move to Step 3

3. Replace the lamp. Does it strike with a fresh lamp?

YES: Old lamp is dead. Leave the new lamp in, reset lamp hours, carry on

NO: Move to step 4

4. Repeat as above for ballast / PSU / each part until you find the guilty bit.

5. When you find the guilty bit and fix the problem, turn the lamp strike sensor back on.

Your profile has you located in Somerset so I think you should look at the PLASA website for a level 3 qualified rigger in your area then explain your situation and ask them if they would be prepared to give you the benefit of their advice for the price of a very [very] nice lunch.

Whilst I understand your principle, I think we should remember that there is no sort of structural design criteria in the Level 3 (or indeed, Level 2) assessments. Now, that's not to say that somebody who has an NRC Level 3 shouldn't be capable of designing a range of truss structures, I'm sure that many, if not most, are. But no more inherently so than a Level 2, and no more inherently so than a suitably experienced person without any NRC qualification. From a CDM perspective, selecting suitably qualified contractors is important and neither NRC certification is really the 'correct' proof of suitability, from a design perspective.

For the most part, from a design, legislative and possibly insurance standpoint, this'd be better with an engineer than with a rigger.

One of the big problems with used truss is getting hold of it. Seriously! Most companies hold onto their truss until there really is a reason to get rid of it, ie damage or fatigue. Where 'tech' - like sound, lighting or video equipment - will become obsolete as newer, lighter, faster, brighter, louder products replace them; things like truss, staging and cable tend to remain in hire stock much longer and are retired only once they are either broken (and beyond fixing being economical), worn out, or just not needed anymore. (The latter being seldom applicable to truss, except things like PAR can pre-rig).

With the main development in truss being the cost of it (going down), if you can even find all the bits you need used, I'd be surprised if the cost of used truss + inspections etc is actually any cheaper than an all-new solution.

As for Somerset... Stage Electrics or Enlightened Lighting would certainly be able to handle something like this.

Not to state the obvious too much but Chamsys Tech Support would probably be a reasonable course of action.

https://chamsyslighting.com/pages/uk-support

Hi. I spend a lot of my time with winches and I agree with the general tone here that caution is needed to proceed. However I would argue that winches, installed and used correctly, are quite safe and indeed relatively straightforward.

You can also argue that whilst there are some safety implications involved in the operation of the machinery... that risk is often going to be a lower risk than that of sustained periods of work atop a tall ladder.

First rule of work at height is not to, unless you have to. Your enquiry to introduce mechanical means of bring the bar down to a safe working level is, in principle, the responsible approach from an H&S angle.

Hello,

I work at a small community hall. We've been offered the opportunity to acquire some second hand electric winches, manufactured by Mole Richardson (UK) ltd in 1998. They appear to be in working order, obviously if we put them in we are going to have them installed and insured properly etc. I can't find any information about this company or the type of winch online, although I have found the manual for the electric motor they used (Seipee, an Italian manufacturer, still trading). I was wondering if anyone here had heard of this equpment, and if anyone would be able to give me any advice on this kind of thing. I'm reluctant to instal things that will be an burden, or you cannot get any spares for.

The thing with winches as you are seeing now is that typically they consist of 5 key components.

1. The chassis (what everything bolts to, plus the drum, leadscrew, secondary brake etc), typically built by whom we would call the 'manufacturer'.

2. The motor (what turns electricity into movement), in this case you have identified that's made my Seipee

3. The gearbox (what will dictate the SWL, and the speed, in conjunction with the motor and of course, all other load bearing parts). That's usually made by yet another party.

4. The rope (obvious), could be Steel Wire Rope, but fibre is common too, or even steel band. Made by another party.

5. The I/O. (Electronics - limit switches, sensors, encoder(s), discreet PLC I/O, local controls etc, as required) Made by yet more parties.

Each will have had a declaration of incorporation (DOI), but not necessarily a declaration of conformity (DOC), Mole Richardson will likely have issued the DOC as a complete machine, so in terms of machinery directive, they are the manufacturer in essence.

So the trouble with old winches tends to be joining all the various dots together from numerous places, to ascertain what is, and does, what.

That said, there can be some perks of that, in respect of retrofitting old mechanical engineering with modern controls etc, which might be impractical in a complete machine due to size and cable limitations etc.

But the challenge - depending on how much information Mole Richardson can provide - is in understanding what the winches were designed for and the limitations they were designed for.

There will have to be a process of looking at all the various components to establish the expected performance, and the limitations, of the machine.

The motor is only half the battle, a small motor can lift big weight with the right gearbox (but will move slowly), and can also move quickly with the right gearbox (for light loads).

The resultant speed and load (and the loading you require) may dictate that varispeed is a necessity ('hard-starting/stopping' a high speed winch can exert very large dynamic loads) and that may then extend to the safety system, where the traditional 'Cat0' stop - cut power and let brakes come on - is unsuitable; so a controlled stop would in that case need to be programmed as part of the Emergency Stop system, that tends to then require more hardware and programming etc. So there's quite a few 'ifs' and 'buts'. A lower speed, lower-SWL winch may well be suitable for a more simple start and stop operation. These winches could be too lightweight for your intended application, or they could be so big that they need controls incorporating to limit their performance. Or if you're lucky, you could be somewhere in the middle.

I would be happy to advise you on this, I have sent you a PM with some more details.

Ultimately I suspect it will need a contractor who is familiar with both the mechanical engineering and the controls.

In order to be compliant, it needs somebody who is familiar with both the electromechanical functioning of the winch, familiar with British and European legislation for lifting equipment, and familiar with theatre-specific standard and codes of practice.

Even if the winches happen to be ready for use immediately, I would think it reasonably likely that you'll need some form of bespoke controls to be produced. Unlike chain hoists, you can't really buy 'off the shelf' motor control.

Sensors and, accordingly, wiring may also need to be modernised to meet modern legislation, in terms of meeting Machinery Directive standards.

I don't want to rule out your winches, but I think there is every scope that a pair of electric chain hoists and a basic 2-channel electric chain hoist controller, 'off-the-shelf', with a shorter install and easier certification, could come out cheaper than recommissioning these winches.

That said, there may be more scope to what your winches can do around your theatre, too - so don't let me talk you out of it, either!

Inspection and maintenance will of course become a factor which needs to be considered and indeed paid for, but I feel this thread might make that sound a bit more complex and expensive than it actually is.

Getting quotes from service providers who carry out this kind of work would be the best way to anticipate what sort of annual costs you're likely to incur... I think that the estimate of £5k a year is quite excessive.