Betapack Demux Upgrades

[langleyn]

I'm a school ICT Curriculum Support bod and a novice to lighting, having inherited the role from the caretaker!. We have 3 Zero 88 Betapack 1s in our school. I would like to upgrade them to DMX as I believe that this would allow us (potentially) to make our music a dance show productions more visually exciting.

 

As far as I'm aware, Zero 88 no longer manufacture upgrade kits for the Beatpack 1s, so I'm wondering what options we have. I no virtually nothing about this subject, but no-one else was prepared to take on the repsonsibility so I'm despreate for all the help and advise I can get.

 

Cheers

Nick Langley

[PDD]

Upgrading to DMX alone won't make your shows more visually exciting, unless you have a suitable DMX control desk with the necessary functions/effects you might need. However, by going DMX you immediately make your system more widely compatible with hired equipment and any new control desk you might buy.

 

If you can't get a DMX upgrade kit for the Betapacks, try looking for a second-hand or new Zero 88 Demux unit. That's a separate unit which can sit with your dimmers, takes in DMX from your desk, and converts it for your existing analogue dimmers.

 

[plug] Lastly, if you need any more advice about school theatres, click the link below! [/plug]

[GridGirl]

Welcome to the Blue Room :D and to the world of theatre lighting :P

 

First question I would ask is what desk are you running? If you upgrade to DMX you'll need a compatible desk - there are loads of threads on the topic of lighting desks in schools, so I won't go into detail here! Also, what lanterns does the school own?

 

A demux unit will allow you to convert your analogue packs to run off DMX - you'll only need a single unit, as each demux can cope with up to 8 packs. They're not difficult to use at all. Have a look through the old lighting threads and you may well find a lot of useful information. Good luck!

 

EDIT: beaten to it!

[WiLL]

you'll only need a single unit, as each demux can cope with up to 8 packs.

hmm, not ALL units, I've got a lightprocessor QDmux which only has four outputs. Worth checking first.

[si_cole]

Just a word of caution - if you are getting a demux you will need to check the polarity of your existing racks. It may well be that you need a negative card (which will handle 4 outputs of the 8 on the demux) if your racks are negative output.

 

Agree with GridGirl - you will need a DMX compatible desk. Please give us more info and we can help you out further

 

HTH

 

EDIT - The "demux" I am quoting is the Zero88 Demux

[DSA]

Just a word of caution - if you are getting a demux you will need to check the polarity of your existing racks. It may well be that you need a negative card (which will handle 4 outputs of the 8 on the demux) if your racks are negative output.

Betapack 1's are autosensing, and therefore can accept either positive or negative inputs, so this is not a problem.

 

David

[peter]

Just to throw a spanner in the works, the Zero88 Demux 48 which si refers to is now a discontinued product. We now do the Demux 24 which is a 1U rack with 4 8pin DIN outlets. Each of these outlets is capable of switching between +ve and -ve output voltages.

 

Hope this clears things up.

[James S]

Just to make this more accurrate (sorry if it adds confusion)

 

Betapakcs are not autosensing IIRC - some are switchable in terms of input - the give away is the power light near the top on the right. If it has text below says, "Red Positive, Green Negative". I think, and the manual I have here suggests that you have to change a setting in the back. However, we have other packs that dont have the text so they may not be adjustable

 

I would suggest the Showtec DEMUX - its switchable, small, low cost etc and fairly reliable. Either way - the output on here can be adjusted so you dont need to worry about the dimmers. I would avoid the Zero 88 demux myself. The one we have is good but not good enough to warrant the price over the showtec one really.

 

The DMX cards are almost impossible to find secondhand (I've only found one so far). New they cost more than the demux above each for only 6 channels so a demux is probably a good plan.

[DSA]

OK. This is a little pedantic, but of relevance. It would appear that I was half right - but to be honest it is a little confusing!

 

The manual states that:

 

Input signals: 0 to +10v or 0 to -10v, autosensing

however the next line states that

Low voltage feed is +/- 20v nominal at 100mA - polarity is set by an internal link.

What this suggests to me is that the input signals are tracked for polarity, but that the LV feed is not. Surely a controller which outputs 0 to -10v, would also provide a negative LV feed, or is this just rubbish? If this is the case then it sounds like the autosensing feature is pointless because you would have to open it up anyway.

 

Perhaps someone could just fill in the gaps here because I am clearly not understanding the specification and it would be useful to know the real answer!

 

Thanks,

David

[bruce]

Surely a controller which outputs 0 to -10v, would also provide a negative LV feed, or is this just rubbish? If this is the case then it sounds like the autosensing feature is pointless because you would have to open it up anyway.

My reading of this is:

 

The controller does not provide a LV feed - it is provided by the dimmer to power the controller!

 

And many controllers will be externally powered and will not utilise this feed.

 

Looking at it another way - there's no way for the betapack to "autosense" what voltage it should be providing.

 

Does that make sense?

[peternewman]

That's my understanding of it certainly Bruce, the 20v feed to power small desks is switchable +ve/-ve but the dimmer will autosense the 0-10v control signals it's sent.

 

PN

[DSA]

Ah I see - so I was correct in saying that the pack does sense the Input voltage. I now understand that pin 7 is a 20V supply for desks without their own supplies, which makes sense! Thanks Bruce.

[richard]

That is correct, I have used Betapack 1's quite a bit with both + and -ve control, the only time I have needed to switch the internal setting across has been when the desk is powered by the dimmers, all other times they have just sorted themselves out..