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What is the difference between LRD** and LR3D** overload relays?

Issue:
What is the difference between LRD** and  LR3D** overload relays?

Product Line:
Tesys D line Overload Relays

Environment:
Products sold and used in the United States

Resolution:
The LRD** overload has single-phase sensitivity and is not designed for single-phase applications. If current is passed through all three legs of the overload, it is possible to prevent nuisance tripping due to ``phase failure``. The LR3D does not have single-phase sensitivity . It does not require current to be passed through all three legs of the overload and thus would not result in nuisance tripping due to ``phase loss``.
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