Hi Robin,
SAP trans. TPM60 is used to calculate NPV - it depends on the Valuation rule (Position Management Procedure) per selected instrument if this is required or not; the result of valuation is recorded in the table VTVBAR.
Another SAP trans. TPM1 is used to execute valuation and records results of this valuation into accounting; TPM60 is prerequisite for TPM1 (if relevant).
So process-wise, at the End of the Month, you first of all run TPM60 and then run TPM1.
regarding your last question - please look at the Update types generated as a result of valuation (TPM1) and then you can verify that is the meaning of these Update types in a relevant Position Management Procedure (SPRO -> ... -> TRM -> Transaction Manager -> General Settings -> Accounting -> Key Date Valuation -> Update Types -> Assign Update Types for Valuation).
Kind regards,
Renatas