differential voltmeter
Also found in: Acronyms.
differential voltmeter
[‚dif·ə′ren·chəl ′vōlt‚mēd·ər] (electricity)
A voltmeter that measures only the difference between a known voltage and an unknown voltage.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.