The 3 indicates RYB and .5 Neutral. In normal conditions,
power supplied is balanced. So, no neutral current flows.
But in case of small unbalanced condtions, low amount of
neutral current has been found and hence to provide the
path for it, neutral wire is provided with half of the
cross section that of phase.
if i conncet ct with ct ratio of 600/5 to an energy meter
having ct ratio of 100/5, the reading show by the meter
will correct, if wrong is there any method to calculate
correct value with shown value, if yes please state