Does anyone know of an available data set for the Illumina EPIC/ 850k array that has files in IDAT format that one can download? I am testing a pipeline before I get my own data back and would like to start with the raw files. Illumina's demo data only has three samples and I would like to test out more.

Thank you in advance!

Why not check GEO whether such data set exist?

All samples submitted that were analyzed on this array: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GPL21145

One of the experiments that has the idat files: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE92579