Question

A dc A-h meter is rated for 15 A, 250 V. The meter constant is 14.4 A-sec/rev. The meter constant at rated voltage may be expressed as

• A. 3750 rev/kWh
• B. 3600 rev/kWh
• C. 1000 rev/kWh
• D. 960 rev/kWh

Answer 1

The correct option is C 1000 rev/kWh

Meter constant,
m=14.4 A-sec/rev

To express meter constant in the unit rev/kWh.

Meter constant
$=M^{{}^{\prime }}=\frac{1}{M}=\frac{1}{14.4}\frac{rev}{A-sec}$

$M^{{}^{\prime }}=\left(\frac{1}{14.4}\frac{rev}{A-sec}\right)\times \left(\frac{1}{250V}\right)\times {10}^3\times \frac{3600sec}{1hr}$

$=\frac{3600\times {10}^3}{14.4\times 250}=1000rev/kWh$