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teberle
09-18-2007, 12:12 PM
Okay, this may be a question that has already been asked and answered but I haven't found anything. I am powering my boards with an external power supply which works fine, but if I chose to power the SSR's with an external power supply do I need to do anything special? Can I just plug 5vDC into the jumper and move on?

A Marchini
09-18-2007, 12:54 PM
Okay, this may be a question that has already been asked and answered but I haven't found anything. I am powering my boards with an external power supply which works fine, but if I chose to power the SSR's with an external power supply do I need to do anything special? Can I just plug 5vDC into the jumper and move on?

I assume you mean the drive voltage for the SSR optoisolator. In which case your power supply can run those as well. Keep in mind how many optos you need to power and their current requirements. Just in case your power supply isn't up to the task.

Tony

teberle
09-18-2007, 02:40 PM
Tony,

Thanks for the reply, I do want to drive the voltage for the SSR's since my parallel port is only putting out 3.8 volts. Do I need to change any of the wiring from the db25 to rj45 adapter to keep from sending power to the board via the parallel port?

Dan Ross
09-18-2007, 04:52 PM
Okay, this may be a question that has already been asked and answered but I haven't found anything. I am powering my boards with an external power supply which works fine, but if I chose to power the SSR's with an external power supply do I need to do anything special? Can I just plug 5vDC into the jumper and move on?


Tony,

Thanks for the reply, I do want to drive the voltage for the SSR's since my parallel port is only putting out 3.8 volts. Do I need to change any of the wiring from the db25 to rj45 adapter to keep from sending power to the board via the parallel port?

Your SSR's are powered from the same power source you power your 595 with, not the parallel port. If you wish to use another external power supply for your SSR's you will need to move the shunts by the 2803 from 1 and 2 to 2 and 3.

Edit - I forgot to mention you will need to bring the SSR external power in on P2 if you move the shunt to position 2 and 3.

teberle
09-18-2007, 06:23 PM
That answers my questions. Thanks