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Old 31-01-2012, 08:16 AM
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Jeffkop (Jeff)
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Join Date: Jan 2008
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Quote:
Originally Posted by peter_4059 View Post
Jeff,

I assume by "referenced" you mean the -ve terminals are made common? How do you tell if a supply is able to be referenced to another?

Peter
Yes -ve terminals commoned.

A very good question Peter ... The recommended way would be by way of circuit diagram or circuit tracing the -ve side visually ... In the main most designs will accommodate referencing though. If I was going to try referencing I would measure the -ve output with respect to earth first ... this may or may not provide a voltage ... (if its 0 then the supply -ve is obviously already referenced to ground) ... if its above or below zero then I would get a low value resistor say 10ohms and connect that to the -ve terminal then connect the other end of the resistor to earth ... (if there is any kind of spark remove it straight away) measure the -ve and also the voltage between the + and - ... if all is OK you should have the correct output voltage and very little between the -ve and earth ... you can safely reference the supply -ve to any other reference if this is the case.
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