The pick-up value of a relay is 7.5 A and the fault current in the relay coil is 30 A. Its plug-setting multiplier is ________.

Correct option is B

​$$\text{The plug-setting multiplier (PSM) is a parameter used to describe the level of fault current in relation to the pick-up value of a relay. It is calculated as the ratio of the fault current to the pick-up value of the relay. The formula is:} \\\text{PSM} = \frac{\text{Fault Current}}{\text{Pick-Up Value}} \\\text{Given the values:} \\\text{Pick-up value of the relay: } 7.5 \, \text{A} \\\text{Fault current in the relay coil: } 30 \, \text{A} \\\text{Using the formula:} \\\text{PSM} = \frac{30 \, \text{A}}{7.5 \, \text{A}} = 4 \\\text{Therefore, the plug-setting multiplier is } 4.$$​​