Practicals and dimmer loads

[Zulu]

Hi,

I'm planning an ameateur production of Bedroom Farce, and there are about 5 practicals required: bedside lights, a couple of wall lights, and perhaps a single ceiling bulb hanging down for the "half decorated" room.

 

I want to use low power household bulbs, generally 60W, independantly controlled through my dimmers and desk.

 

Question: am I likely to suffer from too little power for full control? I don't want to be stuck with a light on which I can't turn off! (Ever been there?). I have 2.4kW Act 6 Strand dimmers.

 

If there is a danger, could I overcome it with just one 'Load' lantern, wired up somehow to serve each practical when the time comes?

 

What dya think?

[Gerry]

This isn't meant to be a daft answer by why don't you just plug in the practicals and try them?

I've often used 60W bulbs in practicals without the need for a dummy load.

Cheers

Gerry

[Andrew C]

Whether you will have a problem really depends on your dimmers. If they are newish, they may well be OK (ISTR that Beta II are ok at 60W)

 

However, putting an extra lantern backstage somewhere in in parallel will work, or pair your practical with a lantern covering the same area is another option.

 

 

Edit:- DOH! Missed that, sorry. Should be OK then.

 

I have 2.4kW Act 6 Strand dimmers.

[gareth]

60w may well be fine on an Act6 rack. But if you do have flickering or non-linear dimming issues, and you need several load lamps, why not build yourself a load box? We have one (a.k.a. "the pie-heater") kicking around at work, which we use on occasions when we need a number of load lamps in one location (fly floor, near a temporary rack, etc.) - it's simply a bunch (eight, IIRC) of BC lampholders in a box with a hinged lid for access, each one with a 100w GLS lamp in it, and with a bundle of 15A tails hanging out of the side.

[dbuckley]

When I did bedroom farce I used normal dimmers for all the pracs with no problems whatsoever. The only pic I have is not great, but...

 

http://www.rangioraplayers.org.nz/productions/perprod/bedroom_farce/photos1/set_700x326.jpg

 

The light switch you can see is practical too - it really did operate the bedroom lights when required.

 

Hint - the bedside light that gets smashed up does not actually have to work!

[Lumiere]

Never trust an actor/actress to operate lights...no,no,no

 

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I remember a show with 5 or 6 practicals, each of which had to be switched independantly,

whilst operating a 60 channel 2preset/2group (yes folks thats manual) desk.

Somehow managed to get 6 switch lines to a made up MK switch panel and left a permanent load on

a p.123 under the stage.

 

Moderation: quote trimmed - there\s no need to quote the previous post in its entirety

[dbuckley]

Never trust an actor/actress to operate lights...no,no,no

 

Absolutely yes, yes, yes!

 

But when I say the light switch was practical, its just a trigger to the control system. The switch is armed when I set it to be so (and at no other time!) and the actor just flips the switch (either way, dont care), and the lighting cue is taken. Once you get used to lights working naturally on stage, doing cues with calls or even visual cues looks just so much less convincing...

[David A]

you can simply use 100 watt lamps in your pracs and don't bring them to full.

[DaveBeattie]

Be careful of using single bulbs as dummy loads. If your system needs dummy loads and the bulb blows (eg mid-show), you will be left with no dummy load and whatever mis-behaviour you were trying to prevent in the first place will recur. I prefer to use a box of resistive loads, but a pair of 60W bulbs per channel is a fair alternative.

 

Regards,

 

Dave

[Zulu]

Thanks, Gerry. I will be trying it, but with limited theatre time, I'm trying think through it all first. Reading yours and other replys, I think I will be ok.

 

cheers, Zulu.

 

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Thanks, Guys. Great responses. It sounds like I'm going to be ok. Thanks for the set photo, Dave. It looks superb. (Spookily similar to ours, with two level, and even the red-blue-yellow colours!). Maybe I'll wire the switches up as well (over-ridden by the desk, of course!)

 

I'll join my practicals to the main lighting where independance isn't required.

 

Lumiere, your suggestion sounds great, but maybe too tricky for me.

 

Dave B, single bulbs as dummy loads does sound iffy. Maybe I'll pursue Gareth's suggestion for future productions.

 

Thanks, one-and-all, Zulu

 

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60w may well be fine on an Act6 rack. But if you do have flickering or non-linear dimming issues, and you need several load lamps, why not build yourself a load box? We have one (a.k.a. "the pie-heater") kicking around at work, which we use on occasions when we need a number of load lamps in one location (fly floor, near a temporary rack, etc.) - it's simply a bunch (eight, IIRC) of BC lampholders in a box with a hinged lid for access, each one with a 100w GLS lamp in it, and with a bundle of 15A tails hanging out of the side.

 

Gareth,

I'm interested in your Pie Warmer, although I don't understand your abbreviations (IIRC, BC, GLS ??) (new boy!). I imagine a wooden box with 8 100w household bulbs and bases in, wired in 4 parallel pairs to 4 channels, with 4 15A flying plugs coming out of one side of the box, and 4 flying 15A sockets coming out of the other. Am I close? Any switches, load resistors, or anything else? Are the bulbs ok burning bright in a closed box? Any overheating issues? I presume the box, when in use, is located next to the dimmers?

 

cheers, Zulu.

[Biskit]

I want to use low power household bulbs, generally 60W, independantly controlled through my dimmers and desk.

 

I have 2.4kW Act 6 Strand dimmers.

 

This page: http://www.strandarchive.co.uk/control/actrange/act.html suggests Act 6 dimmers are have a minimum load of 100W. This may be for the very early versions of the Act 6, so if yours are more recent, you may be okay anyway. Otherwise, it appears a dummy load will be required, or alternatively use 100W lamps at below 100% intensity as someone else suggested.

 

Good luck!

 

Ben.

[danburns]

...although I don't understand your abbreviations (IIRC, BC, GLS ??) (new boy!)...

 

IIRC - If I Recall Correctly

 

BC - Bayonet Cap (when referring to a light bulb). This is as opposed to ES (Edison Screw) lamps.

 

GLS - General Lighting Service (basically a common or garden light bulb)

[Oovis]

Dave B, single bulbs as dummy loads does sound iffy. Maybe I'll pursue Gareth's suggestion for future productions.

In 21 years I've never found a single load lamp per practical to be a problem, even on shows which ran for a couple of years each.

[gareth]

Dave B, single bulbs as dummy loads does sound iffy.

No more iffy than single lamps in any other lighting fixture. You don't double-hang every lantern in your rig just in case a lamp blows, do you? Lamps popping during a show is one of the risks we run - it probably won't happen, but if it does then that's life. Chances are the punters won't notice anyway, and if there's anything "mission-critical" which would really be missed if it popped then perhaps that might be something to double-rig. But I don't know anyone who puts a pair of parallel loads onto a low-wattage prac.

 

Gareth,

I'm interested in your Pie Warmer, although I don't understand your abbreviations (IIRC, BC, GLS ??) (new boy!).

IIRC - if I remember correctly. BC - bayonet cap (standard domestic lightbulb fitting. GLS - general lighting service (bog-standard domestic-type lightbulbs).

 

I imagine a wooden box with 8 100w household bulbs and bases in, wired in 4 parallel pairs to 4 channels, with 4 15A flying plugs coming out of one side of the box, and 4 flying 15A sockets coming out of the other. Am I close? Any switches, load resistors, or anything else? Are the bulbs ok burning bright in a closed box? Any overheating issues? I presume the box, when in use, is located next to the dimmers?

Pretty close! Eight lamps, yes, but wired as eight single circuits rather than four pairs (for the reasons outlined above), and no 15A outlets. Just a wooden box (with the top surface of the lid replaced with lithoplate, as wood would probably scorch a bit with the heat rising off the lamps), eight lampholders screwed to the base, with eight 15A tails coming out of the side. It sits next to wherever the dimmer outlets for the appropriate circuits are - the fly floor, next to a portable rack, wherever. Occasionally we have the need to move it elsewhere - for example, it was last used on a production in our studio, where it was driven by eight channels of a temporary dimmer rack sitting in the corridor outside the space ; sitting it next to the rack, close to passing human traffic, wouldn't be safe (it does get rather warm, hence the name!), so we just extended the cables (a Soca and a couple of lengths of TRS) and put it inside the space, hidden under the steeldeck set.

 

Edit : sorry about duplicating some of the points! Should really read right to the end of a topic before replying! :D

[Biskit]

In 21 years I've never found a single load lamp per practical to be a problem, even on shows which ran for a couple of years each.

 

Surely this would depend on what dimmers you are using! Most good quality dimmers (even going back a few years - Tempus/Permus etc) can cope with loads down to 30 or 40W and still be completely stable and reliable. Cheaper ones (eg. the early Act 6 I quoted) are only designed to work reliably down to 100W. You may 'get away' with lower, but it starts getting iffy! Much older dimmers (eg. Mini II) would be very dodgy at this sort of power level, as I have found!

 

Ben.