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Q:
How can I know whether one device use AC or DC sources phisically??
- Iyung (age 20)
Indonesia
A:
There is no 'sure fire' way of knowing. There are some clues, however. If you measure the resistance of the input plug with an ohmmeter and find a small value, a few tens of Ohms at most, then it is likely there is an input transformer that requires an AC source.
Lee H
Of course it’s important then to know what voltage and frequency it’s designed for. If it’s designed for 120 V (or even worse, for 24 V), it would probably be destroyed if you applied 220V. Mike W.
(published on 10/22/2007)
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