Thank you so much.TreeTops wrote: ↑01 Dec 2022, 05:35The APU switch is left click only. Click click click cycles through the 3 positions. There is no need to be fast.Styggron wrote: ↑01 Dec 2022, 04:00 Yes I read your last sentence re the volt gauge but it does not give me enough information.
Does BAT mean the APU is still powering the plane? or is that BUS? I read over what you wrote multiple times....... hmmmmm
Also I still don't understand what the bottom 3 position switch on the APU does. Makes no sense to me at all. I need to find a clear explanation.
Yes up turns it on, yes middle turns it off..... and down engages the generator, ummm ok so I need to move it from top to bottom FAST because if you stop it at middle it turns off.
Ok so is there a reason you don't want to engage the generator ie why just have RUN??..... and what does engaging the generator do? (yes I know generators turn on and that does ummm errrrr...........) what does it do to the APU? or does the generators MEAN that when THEY are on, each of them gives power FROM the APU **to** engines 1,2,3 and 4........ is that right? It's not is it?
The APU start position allows for the engine to start and warm up before applying the load of the generator.
The APP position engages the generator so now the engine is driving the generator which is supplying voltage to the main electrical bus. This is the position you need for the APU to be 'working'.
Each of the 4 engines when running also supply voltage to the main bus.
The engines are capable of starting off the battery but it is a huge drain and can quickly kill the battery. The APU however, happily supplies enough voltage to start the 4 engines and run the aircraft systems while you start up.
Once the engines are running, they supply voltage to the aircraft and the APU is no longer needed, so it can be shut down.
the BAT position on the dial means how many volts the battery is capable of supplying to the bus.
This is exactly the kind of thing I needed.
Excellent........ absolutely PERFECT..............
Thank you sooooooo much.
So the dial we have there does not transfer electricity to anywhere at all, it is only a selector to read the voltage on the meter coming from the position it is on the dial which you explained in a post above.
Yes?