Butch!
Active Member
A colleague at another school district is having issues with the houselight controls on their circa 1995 Hub/Varalite dimming system and asked me for help, but like most other people, I have very little experience with them and am hoping someone here does. Here's what they've got . . .
The school was built in 1995 or 1996 with a 96 dimmer Hub/Varalite dimming system, I think the nameplate calls it a 'PR96'. Dimmers have TTI stickers on them and there are two firing cards (1-48 & 49-96) and they are TTI as well. There are two other cards in there, looks like one has the transformers to monitor the phases and the other is the processor.
The last 13 dimmers in the rack control the houselights which are almost all 1K can lights. There are two preset slider wall controls (one in the booth, one backstage) and two pushbutton panic switches. The preset slider panels have 'off',' dim',' on' buttons on them, numeric keypads and then a master slider and three channel sliders. The system was set up so each channel slider controls a portion of the houselights. If you press the 'on' button or the panic buttons all 3 of the channels come on to full. If you press the 'dim' button then the sliders actually do something and you can set the look. No one knows what the numeric keypad does and there is no operator's manual anywhere. The stage lighting is controlled by an Express 24/48.
So here's the problem. One day they came in and hit the panic button ('on') to turn on the houselights and the houselights came on, but at less than 50%. They tried both slider panels, the 'dim' setting, the 'on' setting, etc, but all they get is less than 50%. Then they turned on the Express 24/48 and the houselights started 'flashing' going between maybe 30% and 60% in a steady rhythmic pattern. Turn the console off and they stop flashing. Brought in an Express 48/96 and the same thing happens, if there is DMX the houselights flash. If there is no DMX they are at somewhere below 50%. The rest of the dimmers all work fine and respond to the DMX from the Express console.
Put a meter on the houselight dimmers and they're only putting out 47.5 volts, didn't meter them while flashing. Incoming line voltage is around 117 on each phase. Took a look at all the cards and blew the dust off of them, no change. Have tried killing the system with the main breaker and letting rest, but no change. Pulled one of the slider stations and it looks like they are analog as there are over a dozen single #18 or #20 wires running from each station back to the rack. In the rack there is a separate area where all of the little wires from the stations hit a number of PCB boards which mainly have relays and empty relay/IC sockets. We assume that these boards are generating a signal which is going to an analog to DMX converter (or straight to the firing cards) and that something is going wrong in there. But with no manual and no schematics we can't be sure what's going on. For all we know some kid played with the numeric keypad and caused this. For now we've put jumpers on all the SSR's so the dimmers are now locked on and they turn the houselights off with the breakers.
Does anyone have info they can share?? This school system is extremely financially challenged (closing schools and selling the buildings to pay debt) and there's no way they'll find the $$ to replace the system.
Thanks for any insights . .
The school was built in 1995 or 1996 with a 96 dimmer Hub/Varalite dimming system, I think the nameplate calls it a 'PR96'. Dimmers have TTI stickers on them and there are two firing cards (1-48 & 49-96) and they are TTI as well. There are two other cards in there, looks like one has the transformers to monitor the phases and the other is the processor.
The last 13 dimmers in the rack control the houselights which are almost all 1K can lights. There are two preset slider wall controls (one in the booth, one backstage) and two pushbutton panic switches. The preset slider panels have 'off',' dim',' on' buttons on them, numeric keypads and then a master slider and three channel sliders. The system was set up so each channel slider controls a portion of the houselights. If you press the 'on' button or the panic buttons all 3 of the channels come on to full. If you press the 'dim' button then the sliders actually do something and you can set the look. No one knows what the numeric keypad does and there is no operator's manual anywhere. The stage lighting is controlled by an Express 24/48.
So here's the problem. One day they came in and hit the panic button ('on') to turn on the houselights and the houselights came on, but at less than 50%. They tried both slider panels, the 'dim' setting, the 'on' setting, etc, but all they get is less than 50%. Then they turned on the Express 24/48 and the houselights started 'flashing' going between maybe 30% and 60% in a steady rhythmic pattern. Turn the console off and they stop flashing. Brought in an Express 48/96 and the same thing happens, if there is DMX the houselights flash. If there is no DMX they are at somewhere below 50%. The rest of the dimmers all work fine and respond to the DMX from the Express console.
Put a meter on the houselight dimmers and they're only putting out 47.5 volts, didn't meter them while flashing. Incoming line voltage is around 117 on each phase. Took a look at all the cards and blew the dust off of them, no change. Have tried killing the system with the main breaker and letting rest, but no change. Pulled one of the slider stations and it looks like they are analog as there are over a dozen single #18 or #20 wires running from each station back to the rack. In the rack there is a separate area where all of the little wires from the stations hit a number of PCB boards which mainly have relays and empty relay/IC sockets. We assume that these boards are generating a signal which is going to an analog to DMX converter (or straight to the firing cards) and that something is going wrong in there. But with no manual and no schematics we can't be sure what's going on. For all we know some kid played with the numeric keypad and caused this. For now we've put jumpers on all the SSR's so the dimmers are now locked on and they turn the houselights off with the breakers.
Does anyone have info they can share?? This school system is extremely financially challenged (closing schools and selling the buildings to pay debt) and there's no way they'll find the $$ to replace the system.
Thanks for any insights . .
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