IB140012EN For more information visit: www.eaton.com
Instructional Booklet
Effective: March 2021 Page 41
Operation and Maintenance Manual,
Automatic Transfer Switch Controller, ATC-900
Appendix A: Feature List and Status Display Messages
RED BAR FLASHING MESSAGES ALL RED BARS ARE GENERAL ALARMS
1 Lockout Automatic control is disabled but still monitors source status. User must reset
2 Engine Test aborted While in engine test, if either S1 or S2 is removed, the warning will display
3 Closed Transition Fail (1->2) In Closed Transition, the switching device failed to operate correctly from S1 to S2
4 Closed Transition Fail (2->1) In Closed Transition, the switching device failed to operate correctly from S2 to S1
5 In-phase Transition Fail (1->2) With In-Phase, the switching device failed to operate correctly from S1 to S2
6 In-phase Transition Fail (2->1) With In-Phase, the switching device failed to operate correctly from S2 to S1
7 Open Transition Fail (1->2) In Open Transition, the switching device failed to operate correctly from S1 to S2
8 Open Transition Fail (2->1) In Open Transition, the switching device failed to operate correctly from S2 to S1
9 Generator Unavailable When directed to transfer and genertor is not available 
10 Failed to Sync - Frequency With In-Phase or Closed Transition, Failed to sync because of Frequency
11 Failed to Sync - Voltage With In-Phase or Closed Transition, Failed to sync because of Voltage
12 Failed to Sync - Phase Angle With In-Phase or Closed Transition, Failed to sync because of Phase Angle
13 Source 1 Mech Failed to Open The Source 1 Mechanism for a breaker or contactor did not open 
14 Source 1 Mech Failed to Close The Source 1 Mechanism for a breaker or contactor did not close
15 Source 2 Mech Failed to Open The Source 2 Mechanism for a breaker or contactor did not open 
16 Source 2 Mech Failed to Close The Source 2 Mechanism for a breaker or contactor did not close
17 Overran Neutral (S1->N) The mechanism is connected to Source 2 instead of remaining in Neutral.
18 Overran Neutral (S2->N) The mechanism is connected to Source 1 instead of remaining in Neutral.
19 Factory Options Error Internal controller failure.  (clear alarms/reboot)
20 Setpoints Error Internal controller failure.  (clear alarms/reboot)
21 Cal factor Error Internal controller failure.  (clear alarms/reboot)
22 State Error Internal controller failure.  (clear alarms/reboot)
23 Timer Error Internal controller failure.  (clear alarms/reboot)
24 Clock Error Internal controller failure.  (clear alarms/reboot)
25 RAM test Error Internal controller failure.  (clear alarms/reboot)
26 ROM test Error Internal controller failure.  (clear alarms/reboot)
27 Watchdog Internal controller failure.  (clear alarms/reboot)
28 Self-test Error Internal controller failure.  (clear alarms/reboot)
29 Gen Start Communications Internal controller failure.  (clear alarms/reboot)
30 Acc I/O Communications Lost communications to the Accessory I/O Module(s). 
31 NTP Communications Error Lost communications to the NTP module.
32 Clock Sync Error Invalid date/time received from NTP device or Modbus write.
33 NTP Module Error Error code received from NTP module.
34 Firmware Upgrade Required  Previous upgrade attempt interrupted (insert USB and restart upgrade).