I have used this proceedure many times on 81s, mainly AC systems, be prepared to have the patience to let everything come up.
1. Shut down any application software such as Meridian Mail, Max, CCR, or Link with the normal software procedure.
2. Power down IPE first, then Network Shelves, and the Core last. Bring up in reverse order.
*** Do NOT power off any power supplies or cards with their respective face plate power buttons. use the module breaker switches only.
DC switches are much less tolerant then AC switches, if a shelf does not come back up, leave it on and unseat the cards, usually reseating one card will relight the module power supply.