Date: 201810
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Night
Aircraft: Regional Jet 700 ER/LR (CRJ700)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
ATC / advisory: Center ZZZ
Aircraft component: Electrical Power
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Anomaly: Aircraft Equipment Problem Less Severe
Detector: Person Flight Crew
When detected: In-flight
Result: General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: The first hour of the flight was uneventful. We were flying along in cruise flight at FL380. With no warning; we got an AC ESS Caution Message. A few seconds later; L WINDOW HEAT; AVIONICS FAN; DISPLAY COOL; L PITOT HEAT; L AOA HEAT; and STBY PITOT HEAT also appeared. The following white status messages also appeared: STAB CH1 INOP; RECIRC FAN FAULT; L VIB FAULT; R VIB FAULT; GPWS FAIL; MAIN BATT CHGR; EMER LTS ON; SLATS HALF SPEED; FLAPS HALF SPEED; FDR FAIL; WINDSHEAR FAIL; TERRAIN FAIL; DC ESS TIE CLSD; DC MAIN TIE CLSD; ICE DET 1 FAIL. The integral lighting on the Captain's side and center console went out. The cabin crew called up and informed the Captain that the emergency lights were on. All cockpit displays remained working.We diagnosed it as AC ESS bus failure. I maintained the controls and took the radios while the Captain ran the QRH. The QRH called for AC ESS XFER to ALTN. The Captain pushed the switch button with no change. We reviewed the inoperative systems from the QRH. We looked at the AC electrical synoptic page. The GEN 2 was green; showing a load; and had a green line to BUS 2. THE SERV BUS was also powered. The ESS BUS was Amber. BUS 1 was Magenta. GEN 1 and IDG 1 were magenta. The current; voltage; and frequency of GEN 1 was just amber dashes. There was no green line coming out GEN 1.On the DC synoptic page; TRU 2 and ESS TRU 2 were green with normal voltage and current. TRU 1 and ESS TRU 1 had no input lines; were white and showed 0 volts and amps. The MAIN TIE and ESS TIE were closed. All buses were green with the exception of the load shed UTIL BUS.We discussed whether this was just an AC ESS BUS failure. We did not have another caution message; but we had more problems than just that. We reviewed the QRH for AC BUS 1 and GEN 1 but did not run them. We informed ATC of the issue but did not declare an emergency. We informed operations and elected to continue to [destination]. ATC gave us normal step down for our descent. As we descended; we considered resetting GEN 1; but elected to start the APU as a better course.When the APU came online; all of our systems came back online. The caution and status messages all went back to normal. On the AC synoptic page; The APU GEN was green; showed normal current; voltage; and frequency; but did not have a green output line. The BUS 1 was still magenta with no green lines in or out. ESS BUS was green but had no lines leading in. On the DC synoptic page; all TRUs were green with normal load and volts. The only abnormality was the TRU 1 input line was blank but it still showed normal voltage and current output.We continued and landed [using a] visual approach. We taxied to the gate and offloaded without issue.After arriving at the gate; the Captain worked with Maintenance on the phone to diagnose the issue. With the engines running; he reset GEN 1. It would not come on; but the synoptic page returned to when was expected with green lines coming from the APU GEN and GEN 2. All buses we now green. After deferring GEN 1; we continued on with our next flight.I'm still not 100% sure what the problem was. There was some sort of GEN1 failure but we never got a message for that. We never got a caution message for AC BUS 1 failure; but plenty of systems associated with that bus failed. The ACPC did not transfer the loads as expected after a generator failure. The magenta boxes on the AC BUS 1; GEN 1; and IDG 1 lead me to believe there was also some indication failure.I hope this could be shared as an example of non-traditional emergency.




Synopsis: CRJ-700 First Officer reported multiple electrical failures that were related either to a Number 1 generator problem or Essential AC Bus issue.