NP Control Chart (Number Nonconforming) Online
Online np chart: monitor the number of nonconforming units when the subgroup size is constant, automatically calculating the n·p̄ center line and control limits with automatic detection of the eight out-of-control rules.
When is an np chart appropriate?
It applies to attributes data judged as conforming/nonconforming where every subgroup has the same number of units inspected, for example the number of defectives when a fixed 100 pieces are sampled from each lot.