Tester showing reversed polarity on receptacles

Old 03-12-15, 01:00 AM
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Tester showing reversed polarity on receptacles

At my buddy's house he has a few receptacles that are showing a reversed polarity when the tester is plugged in. The light pattern on the tester is indicating this. Neutral and hots are on proper screws. Any idea what else could be causing this issue?

Old 03-12-15, 01:18 AM
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You're saying the white and black wires are on the proper side of the receptacle.
Possibly the black and white wires are reversed before they get there.

Does a table lamp work when plugged in ?

You would need a meter at this point to check the white wire to ground and the black wire to ground for voltage.
Old 03-12-15, 06:12 AM
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On some plug in testers a bad ground can show up as hot/neutral reverse. You can test this by plugging an extension cord in a receptacle with a known-good ground and test voltage between the ground in the extension cord and each of the prongs of the unknown receptacles.
Old 03-12-15, 07:39 AM
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Upstream Problem

Look for a reversed connection upstream from the first problem receptacle.
Old 03-12-15, 07:54 AM
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The plug-in testers are not that reliable in their diagnosis, but will indicate when there is a need for troubleshooting with a meter.

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