Lumel B2 measuring shunts are intended for extending the measuring ranges of direct current of magnetoelectric ammeters, wattmeters and meters of 0.5 classes; 1, 1.5, 2.5.
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Lumel B3 measuring shunts - 150mV are designed to extend measuring ranges of dc ammeters, wattmeters and electrodynamic or ferrodynamic counters which accuracy classes are 0.5...
