Figure 1.13. Work.
1.23. MEASURING VOLTAGE
Voltage is measured by a voltmeter, whose moving coil must have a high resistance to avoid
short-circuiting the voltage. Therefore, the coil is connected in series with this resistance and no shunt is
permissible. Voltmeters are connected across the load; this is distinctly different from the connections
for an ammeter, which is connected in the circuit. Since voltage has been likened to pressure, a
voltmeter can be compared to a pressure gage. It should be noted that neither a voltmeter nor a pressure
gage has anything to do with the main flow. A voltmeter must be connected across the line or across the
load. A significant difference in the appearance of voltmeters and ammeters is that ammeters have
heavier terminals to which the wires are connected. The positive
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