Yes, US and Canada based NRIs can open a Trading account on fulfilling the below conditions:
Customer must be present in India for account opening. Only Face to Face account opening is allowed.
Indian address proof is mandatory.
They need to fill Special designated 3 in 1 trading form designed for US/CANADA based NRIs.
Online trading services are not available for US and Canada based NRI Customers. However, they can place orders through HDFC Securities Relationship Manager.
NO PROXY facility is available to operate HDFC NRI 3-in-1 trading account.