Twin Commander

General Category => Electrical => Topic started by: Roberto Serrano on December 17, 2022, 12:09:21 pm

Title: 840-1000 late electrical system
Post by: Roberto Serrano on December 17, 2022, 12:09:21 pm
What is purpose or why they  put two CB on electrical system on  the 840 and 1000 series on the late models to tie the electrical system between the distribution bus 1 and 2 in case of a failure instead of one CB in the early models
Title: Re: 840-1000 late electrical system
Post by: donv on December 17, 2022, 03:22:46 pm
I believe the idea was to increase separation between the busses in the even of a major short circuit. I think you are talking about the split bus on the 695B, 900, and a very few 840s which had CB panels on both left and right sides of the cockpit. I'm pretty sure no 980s were made with that system.
Title: Re: 840-1000 late electrical system
Post by: Roberto Serrano on December 17, 2022, 05:51:42 pm
Yes, I’m talking about those come with the split bus panel….
thanks for you comments. Let see if someone else come with some  more information.
Title: Re: 840-1000 late electrical system
Post by: donv on December 17, 2022, 08:02:50 pm
I will have to look. I have a 695B AFM which should discuss it.
Title: Re: 840-1000 late electrical system
Post by: Roberto Serrano on December 18, 2022, 09:28:37 am
Donv. I wondering if  I can  email you some info to get a better idea about it.
Title: Re: 840-1000 late electrical system
Post by: donv on December 18, 2022, 10:01:31 am
You can email (or private message) me if you like, but no reason not to just discuss it here. I will see if I can get an answer from Barry Lane, who is the real expert.
Title: Re: 840-1000 late electrical system
Post by: Roberto Serrano on December 18, 2022, 10:05:26 am
Ok.  Barry Lane is in this group ?
Title: Re: 840-1000 late electrical system
Post by: donv on December 18, 2022, 06:06:53 pm
Barry is not, despite my best efforts. However, he is the best Commander training guy around!

Here is what he said:

The split main bus was a response to the European requirement that ALL buses have protection.  The main bus was split and given CB protection.  Those airplanes have bus ties, which you are familiar with their operation. They also have main bus ties which are always in and only trip when there is an issue with the main bus or possibly a generator.  The benefit to the split main bus system is we can now isolate the batteries if there’s a problem there and continue to run the electrical system off of the generators respectively.
Title: Re: 840-1000 late electrical system
Post by: donv on December 18, 2022, 06:07:56 pm
This is Barry's website, in case you need some training:

https://www.thecommanderguy.com
Title: Re: 840-1000 late electrical system
Post by: Roberto Serrano on December 19, 2022, 12:00:06 am
Thank you so much for the answer.