transformers with bar primaries are made for circuits carrying
several thousands of amperes however.
VOLTAGE OR POTENTIAL
A d.c. ammeter is converted into a voltmeter by the addition of a
series resistor or multiplier which limits the current at full rated volt-
age to that required to give full scale deflection of the movement.
Up to about 1000 V this arrangement is quite satisfactory. Insulat-
ing the meter movement, the terminals and the multiplier from the
case and the panel in which the meter is situated presents no special
hazards begin to present themselves. The cables to