electrostatic voltmeter
Inventory Number2012-1-0044
ClassificationVoltmeter
Subject
Maker
Rawson Electrical Instrument Company
1918 - 1968
Cultural Region
Place of Origin
Place of Use
Dimensions15.4 × 23.8 × 24 cm (6 1/16 × 9 3/8 × 9 7/16 in.)
Material
DescriptionSquare walnut case with flat leather handle and hinged lid.
Inside is the instrument, with a bakelite casing. Fan-shaped window at bottom of the panel, knife-edged needle and a reflective band under the scale.
Single scale non-linear , 0-100 volts.
Above the scale on left black capped binding post with silver ring at base, labeled “HIGH”. On right black capped binding post labeled “GROUND” and fuse below labeled “1/100 AMP”.
At center is raised disc with "CLAMP" dial and “ZERO” dial, arrow on “CLAMP “ dial and labeled above dials “UNCLAMP BEFORE USING”.
Inside is the instrument, with a bakelite casing. Fan-shaped window at bottom of the panel, knife-edged needle and a reflective band under the scale.
Single scale non-linear , 0-100 volts.
Above the scale on left black capped binding post with silver ring at base, labeled “HIGH”. On right black capped binding post labeled “GROUND” and fuse below labeled “1/100 AMP”.
At center is raised disc with "CLAMP" dial and “ZERO” dial, arrow on “CLAMP “ dial and labeled above dials “UNCLAMP BEFORE USING”.
Signedprinted on face of meter: TYPE 518 No. 10862 RAWSON ELECTRICAL INSTRUMENT CO., INC. / CAMBRIDGE, MASS. / ELECTROSTATIC VOLTMETER
FunctionA voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit.
An electrostatic voltmeter is one in which the voltage to be measured is applied between fixed and movable metal vanes; the resulting electrostatic force deflects the movable vane against the tension of a spring.
An electrostatic voltmeter is one in which the voltage to be measured is applied between fixed and movable metal vanes; the resulting electrostatic force deflects the movable vane against the tension of a spring.
Rawson Electrical Instrument Company
Date: 1960s
Accessories: the probe 2012-1-0036 plugs to this instrument
Object number: 2012-1-0035
