A common question is "why cant we recharge the battery when we plug an external power in"? In this video we will discuss the reasoning. Click Subscribe to be notified of future EuroSafety Videos www.eurosafety.us training@eurosafety.us
What are the reasons that you would want to plug in an APU prior to turning the battery switch on? I think that's the natural progression but nonetheless I'm curious. Also, please keep these videos coming. They have all been fantastic. Thank you.
Thank you! Regarding plugging in external power prior to battery application in most Airbus products, the main reason is that if you engage the battery first the K2 relay closes the K5 relay. If you then plug in external power the K2 relay switches sides to power the K6 relay. During this momentary switching of power... power is lost to the FADEC (EECU) and the VEMD momentarily. This causes a fault to appear and a amber GOV light illuminates. The only way to get rid of the amber GOV light is to then turn off all power and re engage.
Is this still the case for SD2 and FX2 series? They have a seperate BAT and BUS switches which means that the system functions completely differently from the designs you're referencing. Whilst I do not have strong opinions on either, as I understand it the appeal was to replace the Safran with the LTS so you didn't have to deal with their "support" and in addition to this, Eurocopter/Airbus wiring with their own designs
The soloy modification keeps the same electrical system. The Heli-Lynx installs a completely different electrical system. In the FX you also can not recharge the battery. The FX conversion for the 355 did simply the electrical system and reduce the aircraft weight because of the removal of wiring. The electrical modification for the 350 is different but not lighter. The catalyst that had the mod popular when it was introduced was the pronounced price increase at Turbomeca for overhaul. The historical issues of the LTS failing is what destroyed its popularity when it came out. The issues were mostly fixed but when operators started have fuel control failures and engine chip issues the industry quickly moved back away from the engine. I am not saying it is not a good platform, I am just relaying the industry mindset.
Yes for a split second it does not. That is why if you plug in the GPU after the battery is on in a FADEC equipped helicopter you will get the amber GOV light. The reason the light does not illuminate after the start is that the alternator is supplying power to the FADEC after 60% N1
