NDC is linked to choosing right measuring instrument with right least count (1/10th least count). If the measuring instrument's least count is not 1/10th of tolerance, NDC will fail.
Senior Quality Engineer, Certified Auditor-IATF/ISO45001/14001, LSSBB Certified Engineer, Certified by AIAG & Expert in 5 QC Tool, Certified QMS Engineer by QHI, AIAG VDA DFMEA Expert, SAP QM, Expert in FMEA, DRBFM.
What is NDC in MSA ? And What is the Relation between GRR and NDC in MSA ? #Part_11 The #ndc is one of the criteria used by the #MSA to determine the #sensitivity of the measuring equipment. It indicates the “Number of Distinct Categories” that can be clearly distinguished by the measurement system being used. In Measurement Systems Analysis (MSA), NDC stands for Number of Distinct Categories. It's a metric that measures how well a measurement system can differentiate between different levels of variability in a process. Here are some things to know about NDC:- #NDC:- The number of categories that the measurement system can distinguish. It's a criterion used to determine the sensitivity of the measuring equipment. #GRR:- The repeatability and reproducibility of the measurement system. It measures the variability in measurements, but doesn't reveal anything about their accuracy. #Reliability:- The minimum NDC value is 5 or greater, which determines the reliability of the collected data. #Sensitivity:- NDC is one of the criteria used to determine the sensitivity of the measuring equipment. #Interpretation:- A higher NDC value indicates that the tool is better able to distinguish one part from another. #Calculation:- If the NDC is less than 5, there isn't enough variation in the parts to use the Average and Range Method or the ANOVA method to calculate Gage R&R. The Number of Distinct Categories (#NDC) and Gage #Repeatability and #Reproducibility (#GRR) are related by the #formula:- NDC = 1.41*(PV/GR&R). Although MSA literature and AIAG Manuals treat NDC and GRR as independent parameters, some say that they are actually linked by an exact relationship. This means that the double requirement of both NDC and GRR is redundant and unnecessary.