Emergency Electrical configuration A320

[saviboy]

Hello everyone,

I apologize in advance if this has been discussed before but I couldn't find anything using the search function. Also, some of the discussions on that topic are quite old and I was concerned to read old references that may be out of date.

Throughout the Avionics smoke/smoke procedure, the crew has the option to set the emergency elec. config if desired.
I would like to know why the crew should: "APPLY ELEC EMER CONFIG PROCEDURE, BUT DO NOT RESET GEN, EVEN IF REQUESTED BY ECAM." QRH 27.01C

I think there is an explanation in the FCTM that applies to that step but I don't get it.

"If at least one battery is charging when one side and then the other side of the electrical system are shed, the DC1, DC2, and BAT bus bars become inoperative for the remainder of the flight.
Therefore, the procedure for attempting to partially shed the electrical system was removed from the smoke procedure. This change in the procedure is to enable the flight crew to recover the normal electrical configuration for landing, particularly to recover normal braking. If the flight crew sets the electrical emergency configuration following a smoke detection in the avionic compartment ("AVIONICS SMOKE" ECAM caution triggered), the ECAM does not display the same procedure as the one displayed following the loss of main generators. In fact in this case, the ECAM displays a specific procedure that takes into account the smoke detection: As the flight crew has voluntarily set the electrical emergency configuration, the purpose of the ELEC EMER CONFIG ECAM procedure is not to try to restore the generators, but to remain in electrical emergency configuration, and restore generators before landing to perform the landing in normal electrical configuration." FCTM PR-AEP-SMOKE P 8/10

Thanks in advance

[Flo121142]

The purpose of the Avionic Smoke procedure is to reduce or eliminate the source of the fire. If the origin of the fire is suspect to be electric/wiring (or can not be determined, as electrical smoke/fire is deemed the most severe case), this is archived by shedding all non essential loads, i.e. by placing the aircraft in Electrical Emergency Configuration. Therefore the objective is to stay in Electrical Emergency Configuration until shortly before landing and then restore normal electrical configuration, to enable normal braking. This is why you do not reset the generators in this case.

[saviboy]

The purpose of the Avionic Smoke procedure is to reduce or eliminate the source of the fire. If the origin of the fire is suspect to be electric/wiring (or can not be determined, as electrical smoke/fire is deemed the most severe case), this is archived by shedding all non essential loads, i.e. by placing the aircraft in Electrical Emergency Configuration. Therefore the objective is to stay in Electrical Emergency Configuration until shortly before landing and then restore normal electrical configuration, to enable normal braking. This is why you do not reset the generators in this case.

Ok. Thanks for the reply.

1) Is it because after you apply the steps below, ECAM will tell you to reset "GEN 1+2.....OFF THEN ON" ?

"TO SET ELEC EMER CONFIG
EMER ELEC GEN 1 LINE.......................................OFF
EMER ELEC PWR.......................................... MAN ON"

2) "If at least one battery is charging when one side and then the other side of the electrical system are shed, the DC1, DC2, and BAT bus bars become inoperative for the remainder of the flight"

Can somebody expand on that statement?

3) Additionally, what change is the FCTM referring to? How was the procedure written before?

"Therefore, the procedure for attempting to partially shed the electrical system was removed from the smoke procedure. This change in the procedure is to enable the flight crew to recover the normal electrical configuration for landing, particularly to recover normal braking"





Thanks again.

[Flo121142]

1) Yes, it's because the ECAM may or may not 'know' that you voluntarily set the electrical emergency configuration, depending on if the Avionic Smoke ECAM was triggered or not. If it was triggered, it will display a modified ECAM for the ELEC EMER which should not tell you to reset the GENs, but if it was not triggered it will display the 'normal' ELEC EMER ECAM which tells you to reset the GENs.
3) A few years ago there was a procedure to switch off the bus tie and then switch off one GEN first to see if it eliminates the problem, if it did to leave it off, if it did not eliminate the problem, that GEN was switched back to on and the other one was switched off to see if that would solve the problem. I do not have the old FCOM here, but I think it already gave you the option to select electrical emergency configuration if all of this didn't work.

[saviboy]

Thanks for the reply.

for number 3) I think that step is still in the FCOM: PRO-ABN-ELEC P 169/214 REV: 05 JUN 19