On a 208 volt meter the lowest allowable input voltage is

On a 208 volt meter the lowest allowable input voltage is

• A. 187.2
• B. 180
• C. 200
• D. 190

Answer: (A)

Meters have an operating range defined by how far the voltage can sag below the nominal value while still reading accurately. For many instruments, the lower limit is 90% of the nominal voltage. So for a 208 V system, 0.9 × 208 = 187.2 V. That means the lowest allowable input voltage to stay within the meter’s specified accuracy is 187.2 V. Values like 180 V would be below that limit and could cause inaccurate readings, while 200 V or 190 V are above the minimum threshold but not the lowest.

Meters have an operating range defined by how far the voltage can sag below the nominal value while still reading accurately. For many instruments, the lower limit is 90% of the nominal voltage. So for a 208 V system, 0.9 × 208 = 187.2 V. That means the lowest allowable input voltage to stay within the meter’s specified accuracy is 187.2 V. Values like 180 V would be below that limit and could cause inaccurate readings, while 200 V or 190 V are above the minimum threshold but not the lowest.