Level 12

[Travers]

Hi, I work in a school and we have a very old system. Most of are lighting desks are broken. Before the summer holidays we got a second hand Level 12, I tested it with a betapack 2 and all was working fine. Got back from the holidays went to see if it worked. I pluged one DIN cable into a Betapack 1 and the other into the betapack2. The betapack 2 is now dead and and im getting no control with the betapack1. The betapack1 works perfectly with another desk. I have tried pluging both DIN leads into 2 betapack1's and still nothing. The green lights on the dimmers go off when connected and no light on the act 12. Please help. :?

[kgallen]

Hi,

 

It sounds like you know what you are doing but it may be worth checking the following:

 

The desk requires a power supply feed from the dimmer. This is fed back along the control cable (on pin 7 of the 8-pib DIN connector). This is usually +20V. If the Level 12 has come from an installation that uses e.g. Strand dimmers which use negative voltage signalling, it may have had an inverter kit fitted in which case it will require a -20V supply.

 

The Betapacks can be set to provide either +20V or -20V. In the Betapack1 this is a link on the PCB behind the back cover. For a Betapack2 this is a small switch on the front of the dimmer next to the 8-pin DIN socket (maybe behind a grey panel fixed with a screw). Manuals for both products are still available from the Zero88 website.

 

In both cases there will be an LED on the front of the dimmer. If it is red then the dimmer is supplying +20V. If it is green then -20V. Check your Betapack1 and Betapack2 are showing the same colour - you should do this by turning on the dimmers _without_ the control cables connected.

 

You should then connect the control cable from say you Betapack1 dimmer to the desk (say Ch1-6). Turn on the dimmer and see if the LED on the front of the Level 12 comes on. Repeat this with only the Betapack2. Then again with the control cable plugged into Ch7-12 of the Level 12. Repeat with the Betapack1.

 

If in any of the combinations above the desk LED does not light, then the dimmer is providing the wrong polarity of voltage. Move the link or flick the switch on the dimmer as I have indicated above.

 

If the Level 12 has an inverter module fitted to only one set of channels then it may be that you have to set one of your dimmers to +20V and one to -20V. Note that the desk is then using +10V signalling on one set and -10V on the other set. However both types of Betapack will autosense the control voltage polarity from the desk and work automatically.

 

If you do ascertain that the Level 12 does have an inverter module then any user of the desk/dimmer combination will need to make sure they always connect the dimmers to the desk in the correct association. Alternatively you could remove the inverter kit, set both dimmers to +20V and plug and play any way round you want.

 

Hope this helps.

[Travers]

Thanks.

 

Tried it and it worked first time. We had used the Betapacks with strand lighting desks before so I needed to change it to + volts. The Betapack2 is still compleatly dead though. I will be sending it off soon.

 

Thanks for your help

[kgallen]

Before you send your Betapack2 back, check the control electronics fuse behind the back cover as it may be blown. If you need to replace it, contact the Zero88 guys unless you have a 50mA T (timedelay) fuse (and I think it is a 20mm glass fuse) or can order the appropriate part from RS/CPC etc (at about 20p!).

 

If you bought the B2 new, then I believe a spare fuse was provided with the product.

 

I'm assuming you've tried the dimmer in a known-good power outliet!

 

If you then don't get the front panel LED lit maybe the Zero88 guys can make some suggestions before you send it away.

 

If one or more of the front panel neons is lit, then an individual channel fuse is blown. These are 32x6.3mm 10A F (rapid) HRC ceramic fuses. Again a spare was provided at new or Zero88/RS can help you out.