The AVAB PDD III light dimmer system is built for 96 channels of 10A capacity per channel. A full stocked rack would be able of pulling a total of 960A at 230VAC, pulling over 200kW, just for lights in a theater! This system dates back to 1997, and even earlier with its version 2 and 1 taken into account. AVAB has a lot of great images of their old and vintage equipment on their Facebook page.
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Inside the AVAB PDD III Light Dimmer
The AVAB PDD III dimmer module consists of a 325-531 Card Local Link III, which is the control board of the module. Two driver / filter boards are marked 300-369 Card PDD III Filter Rev. C, this board is the driver between the controller and the TRIAC
It uses a Philips 80C31BH-316WP 8-bit microcontroller, running at 16 MHz. There is 6 channels per dimmer module, each channel is controlled by a single ST BT40-700B TRIAC, in the RD91 package. The Sharp S21ME3 TRIAC driver is a phototriac coupler for isolation between controller and TRIAC.
