Dimmer Doubling/Multiplex vs. Normal

[Briguy90]

My main question here is I am wondering if I can leave my Sensor Rack in normal mode and still have the dimmer doubles work. Basically I do not like the intensity loss from the dimmers when they are in multiplex mode. I would like to be able to use the dimmer double settings without loss of signal.

Will the Dimmer Double device still work with sensor racks in normal mode?
Will Regular lights be affected by sensor rack in Multiplex mode?

 

[sk8rsdad]

I'm struggling to make sense of the question. Does "normal" mean "not configured for dimmer doubling"? Does multiplex mean "configured for dimmer doubling"? Dimmer doubling is configured per dimmer for CEM's running 3.x software or newer, rather than for the whole rack .

A dimmer double device is at it's heart a pair of diodes and a big heat sink which make the device connected to the A or B output see only half of the waveform. The sensor rack can manage each half of the waveform independently if doubling is enabled. In normal mode the dimmer doubler behaves like an expensive two-fer since both positive and negative halves of the waveform are not being managed independently.

A dimmer doubled devices requires a 550W 77V lamp in the fixture. If there's a 115/120V lamp in the fixture then it will appear dim since it is operating at about half it's rated voltage. Also, it does not conform with ETC's specification for allowed loads.

 

[Briguy90]

Well my issue is that I have two difference spaces that use the same dimmers, one of the spaces uses dimmer doublers and the other we use regular 575w S4 units. We distinguish which space is using the dimmers at a specific time by turning off breakers at the hard patch panel. It is not possible for me to switch each and ever dimmer over to Normal and then into Dimmer Double mode each time I go about changing them. So I was hoping that I could leave the dimmers in normal mode and still be able to use/split the dimmer doubles in the other room in this mode without having to change the mode on the dimmers each day.

 

[DavidNorth]

Yes, you can do this, but the Dimmer Doubler will act as a twofer.

So yes, if you are using 115V/120V lamps with a Dimmer Doubler, then not matter what setting the dimmer is on, the lamps will only ever go to half intensity. DD fixtures are also supposed to have a non-standard power connector on them to prevent interconnects with higher voltage sources.

Regular lights plugged into dimmers set for DD mode will act correctly, but only if you patch both control numbers into the same channel on the console. A DD'd outlet has two control channels whether a DD is plugged into it or not. Make sense?

A Dimmer Doubler is used on settings called Dimmer Doubling, or in the case of very old software, Multiplexing.

Does that help?

David

 

[robartsd]

Well my issue is that I have two difference spaces that use the same dimmers

My first thought is that you have a rack that moves between the spaces.

We distinguish which space is using the dimmers at a specific time by turning off breakers at the hard patch panel

Now it sounds more likely that this is an installed rack that feeds two performing spaces through some sort of patch bay.

It is not possible for me to switch each and ever dimmer over to Normal and then into Dimmer Double mode each time I go about changing them.

This sounds like your control module is set up to select dimmer doubling on individual dimmers rather than the whole rack.

Since there is an issue for the space where dimmer doublers are not in use when dimmer doubling is on, it sounds like you have at least some dimmers patched to both spaces (using the breakers in the "hard patch panel" to select which space receives the dimmer output. This sounds like a very hackish retrofit situation. It is unclear how the spaces are used, but it seems that switching which space is using the dimmers is frequent enough that it is a hassle to configure the dimmer doubling every time.

Regular lights plugged into dimmers set for DD mode will act correctly, but only if you patch both control numbers into the same channel on the console.

As our friendly CB member from ETC points out, it is possible to configure a console to output normal waveforms from a dimmer configured for doubling. There are two ways I see modifying your patch to reduce the hassle:

• Configure the soft patch for the space that doesn't use dimmer doublers to output a channel mapped to a doubled dimmer on both halfs of the dimmer.
• Configure the rack to switch between all dimmers doubled and no dimmers doubled and adjust the soft patch for any dimmers that are not doubled in the space that uses doubled dimmers.

Either of these solutions is likely to require your console to output more DMX addresse than you have been using. If you are close to your address limits for your console(s) this could be a problem.

I am a bit concerned about "turning off breakers at the hard patch panel". If the patch panel is allowing a dimmer to be connected to circuits in both spaces at once, it may be easy to overload a dimmer by not switching the breakers correctly. Also circuit breakers aren't designed to be switched on and off a lot, so you could be wearing them out prematurely. Perhaps if you post more about your space, CB members will give you some useful advice for making improvements and/or alert you to more potential problems.

 

[JD]

As long as your 77 volt units are always connected to the DD splitters, it doesn't matter. Plug them into standard AC 120 volts, and the lamps will still only get the equivalent of 77 volts and will work normally.
The bigger concern it that it sounds like you are using circuit breakers as switches. This is a no-no. Wear radically increases the chances that the breakers will not perform their designed safety duty when called upon to do so.

 

[MikeJ]

So, just because nobody has quoted the NEC yet this thread, to show how gosh darn smart they are and everyone else is a dumb-dumb.

NEC 2011
404.11 Circuit Breakers as Switches. A hand-operable circuit breaker equipped with a lever or handle, or a power-operated circuit breaker capable of being opened by hand in the event of a power failure, shall be permitted to serve as a switch if it has the required number of poles.

 

[MikeJ]

I'm sure you can find data on the number of on/off and overload tripping cycles, but generally, its a lot. Even if its only 10,000 cycles, that 27 years switching on and off once per day. I can find no evidence that using a breaker as a switch, which is how basically all touring racks are designed, causes the breakers to trip at a lower rating.