4/18/17 Construction Continues

Finished the Annunciator Testing software. Made up the ribbons cables to connect Annunciator box to Driver cards. To recap, I’m using the Christmas tree lights – the incandescent type. I had tried super bright white LEDs, but their output was focused and did not ‘fill out’ each annunciator box.

Started the software, went to Annunciator Testing and boom – out went the lights. Everything shutdown. Disconnected the ribbon cables, restarted the PS and computer. Ran the software again. Using the logic probe, I saw the trigger lines going Hi/Low – just like they should.

Powered down, reconnected ribbon cables and restarted. When entering the Annunciator Testing module – boom – lights went out again. Disconnected ribbon cables and restarted. Now I applied power directly to each Annunciator light. After four lights were on, power supply tripped off.

Looks like my ‘used’ power supply isn’t up to the task. Each light in the panel draws about 200 mA. So if all of the lights are on at the same time, it will draw around 6.4 amps. During POC, I only triggered two of the lights at the same time. So lessons learned, during POC, put a full load on the power supply!
In 1984, I used a separate transformer/bridge/caps to power the Annunciator lights. Kind of dangerous because the transformer was 7 volts and the 8255s that triggered the transistors were at 5 volts.

Placed an order for a Cosair 750W power supply. This should provide 25 amps at 5 volts. Amazon said it will arrive Thursday.

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