Not sure of the context around this question so will answer a bit more generic than normal...

When you do an exit_opc, opc and the Pim will close and respawn. OPC needs to then establish sockets, etc and download the PG config from the call router. After the config is downloaded the Pim will attempt to go active and establish it's connection. Depending upon the amount of configuration needing to be downloaded to the PG from the peripheral and how fast it's able to establish a connection - that would give you the over all time.

In day to day scope if you need to reset the PG and download the config from the Central Controller - exit_opc will provide the fastest means for that to happen. Also in practical experience in most cases this is under 60 seconds. This certainly isn't a guarentee and may not be the best option depending on the goal but hope it helps!

Skippy