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Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 2:24 am
by sharpless281
Is the FMS on the FMC suppose to come on when the battery is powered on, I am putting the check list in fore flight. I thought the flight plans were usually entered before start. Just asking
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 2:51 am
by norcali.pilot
The FMC turns on with the Avionics Master ON with power coming from an external source, battery master, or generators
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 4:48 am
by sharpless281
That does not happen. Battery Bus is norm, Master battery on, Avionics On.
It comes on only after engine start and a generator reset/on
Which is exactly what one of the YouTube videos on the product page does.
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 1:43 pm
by kevin_firth
sharpless281 wrote: ↑Mon Feb 22, 2021 4:48 am
That does not happen. Battery Bus is norm, Master battery on, Avionics On.
It comes on only after engine start and a generator reset/on
Which is exactly what one of the YouTube videos on the product page does.
2 words, bus ties...?
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 3:23 pm
by sharpless281
Thank Kevin. I tried to set the MVAMS to ready to start and when I turned on Avionics I still do not see the FMC power up. I am ok with that, just wondered why. It starts after I start the engine and reset the GEN (L or R) so that's ok. I found a few websites on the bus ties so I will do some reading, thanks
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 4:11 pm
by kevin_firth
sharpless281 wrote: ↑Mon Feb 22, 2021 3:23 pm
Thank Kevin. I tried to set the MVAMS to ready to start and when I turned on Avionics I still do not see the FMC power up. I am ok with that, just wondered why. It starts after I start the engine and reset the GEN (L or R) so that's ok. I found a few websites on the bus ties so I will do some reading, thanks
I'll have a play around tonight to be sure, but I never try to power up the master avionics unless an engine is running or a GPU is connected. In both circumstances I get a powered up FMC. I think I read somewhere that connecting ground power automatically ties the buses? (As I recall)
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 8:55 pm
by kevin_firth
https://youtu.be/_ZEHTTJ0auc
It was the Gen Ties you were after
Re: Why does the FMS not come on until after start
Posted: Mon Feb 22, 2021 9:03 pm
by sharpless281
ok thank u I will try that, it is part of the checklist
Just did that worked with the Gen Ties