what it means for a "source" or "sink" to be floating

Discussion in 'The Projects Forum' started by SSR's, Mar 21, 2011.

  1. SSR's

    Thread Starter New Member

    Mar 21, 2011
    what it means for a "source" or "sink" to be floating. What are the consequences of associated devices being floating or non-floating? Is the multimeter floating or not? What about the oscilloscope? What about the power supplies? It is extremely important to understand and keep this in mind when "wiring" sensors and industrial computer systems? For example, is the SSR system floating or not? Distinguish between "computer" and "field side" as well as high power vs low power (signal) circuits.
  2. GetDeviceInfo

    AAC Fanatic!

    Jun 7, 2009
    'floating' typically means undefined, or without reference. Sinking and sourcing typically refer to a signal, which, if left floating, may go into uncontrolled oscillation. That is why unused pins or functions, are 'tied' to a known level.

    When used in reference to power supplys, 'floating' means without refernce, where power sections are not interconnected and hence have no common reference point. This is typically done for isolation. An example would be a noisy field environment supplying sensor power which in turn signals to a PLC whose power supply is well conditioned.
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