Eaton ATC-900 - Page 40

For more information visit: www.eaton.com IB140012EN
Instructional Booklet
Page 40 Effective: March 2021
Operation and Maintenance Manual,
Automatic Transfer Switch Controller, ATC-900
-Immediately turn on Gen Start for both Sources
Source 2
Available?
Source 1
Available?
-Set transfer switch to Source 1 (No TDN or TDEN if switch
was previously on Source 2)
-Turn off Source 2 Gen Start after fixed 5 minute TDEC.
-Set Source 2 to Idle state
Yes
No No
-Set transfer switch to Source 2 (No TDN or TDNE if switch
was previously on Source 1)
-Turn off Source 1 Gen Start after fixed 5 minute TDEC.
-Set Source 1 to Idle state.
Yes
Secondary-In
Active?
-Turn off Gen Start for both sources
-Set both sources to Idle state
-Follow normal procedures to transfer between
sources based on source availability, etc.
Wait for next
Secondary-In Active
Secondary-In goes
Active
Yes
No
Secondary Controller with No Preferred Source
* Gen Start of the slower source will be kept on until
it starts, then TDEC set to 5 minutes to turn it back
off.