Home:  Test: WR MORRIS HOT WIRE AMMETER, 1930's

WR MORRIS HOT WIRE AMMETER, 1930's

View all Test

WR MORRIS HOT WIRE AMMETER, 1930's

Hot Wire Ammeters work the expansion and contraction of a piece of wire when heated by an electric current. Although not very accurate and prone to ageing effects of the wire, they were an inexpensive way of indicating currents of over 100 Milliamps.
Smaller current versions would have made the wire too fragile.

Your comments:

  • Hot wire ammeters have the advantage that they not only show DC currents, but they show true RMS for AC currents without modification. Subject to design, this could include RF current.
    .......... Simon Attwood, Aldershot, UK, 7th of November 2010

Add a memory or information about this object

A0722



2007 The Museum of Technology, The Great War and WWII
Company registered in England No. 7452160, Registered Charity No. 1140352, Accredited Museum No. 2221