snoop9erdog
Well Known Member
Tell me what you think. After days of reading and researching for my RV9 for what I want my electrical to be in Mr. Reeves awesome sight I have come to the conclusion that there are three main camps of Electrical:
1. The Modern VPX ECB's - There was a VPX bash in this thread "To VPX or No VPX" where the majority of posters seemed to think the world was ending with the "all eggs in one basket" issue of failure modes (yet, ignoring Marks backup methods in case of box failure). The Glass panel integration of this box and circuit troubleshooting would be fantastic. It is expensive but seems convenient.
2. The Standard Wiring Method - Many advocated for the less expensive and proven CB's, Buss's, Fuses, etc. When reading Bob's awesome book you are introduced to basic bare bones 1950's wiring that evolves into applications of Essential Buss architecture. Much of this makes sense ...however.......there is a current thread talking about "to relay or just use a switch".....this opened up discussion about points of failure again that "don't kid yourself, relays and diodes and switches do fail".
Ok so, if due to the possibility of aforementioned potential failures + some others (alternator, etc.), people are equipping with essential buss's........isn't it a little hypocritical or ironic that many will jump on the bandwagon to discredit a VPX system with equivalent backups?
Afterall....stepping back and looking at the big picture of risk....isn't the big fan out front a big potential "single point of failure, all eggs in one basket" item? Which leads me to the third camp...
3. Bare bone architecture w/Modern Backup (Essential Backups are way outdated and not really practical for Glass Panels nowadays). In other words, all we/you need is to essentially go back to Van's supplied wiring diagrams and then utilize the backup batteries (4 hour endurance that will outlast vans standard tanks) for PFD, G5, carry an old Garmin pilot or equivalent GPS and a handheld comm for backup. Bingo??
However, I did see and like the concept of Ironflights electrical method of utilizing a small lightweight 5AH battery that is constantly charging and has all of his buss'e tied together by a multitude of diodes that enables a hands off approach to not having to remember any backup sequence in the heat of the moment. Just flip master batt with backup batt and leave it alone.
Conclusion and question:
The above is my observation, and after thinking about it, I'm leaning towards wiring my craft with a simple basic single buss system that utilizes the current modern unit/LRU designated backup batteries....and possibly using the IBBS or similar to backup ONLY the GTN, Autopilot, & Engine Instruments. KISS
The question is: Is that sufficient backup for a Basic IFR with Pmags machine?...or....would you go a step further and put those items on a completely separate backup fuse buss connected to a backup SD-8 coming off the battery (bypass the master contactor)? But then again.....now I'm back to an essential buss with diode connecting the system.
Given the modern day Glass panel setups and for the gents out there flying with experience on their panels, how would you approach it now if you had to do it all over again?
Sorry if too long but maybe it will help someone in the planning stage.
Thx for the input
1. The Modern VPX ECB's - There was a VPX bash in this thread "To VPX or No VPX" where the majority of posters seemed to think the world was ending with the "all eggs in one basket" issue of failure modes (yet, ignoring Marks backup methods in case of box failure). The Glass panel integration of this box and circuit troubleshooting would be fantastic. It is expensive but seems convenient.
2. The Standard Wiring Method - Many advocated for the less expensive and proven CB's, Buss's, Fuses, etc. When reading Bob's awesome book you are introduced to basic bare bones 1950's wiring that evolves into applications of Essential Buss architecture. Much of this makes sense ...however.......there is a current thread talking about "to relay or just use a switch".....this opened up discussion about points of failure again that "don't kid yourself, relays and diodes and switches do fail".
Ok so, if due to the possibility of aforementioned potential failures + some others (alternator, etc.), people are equipping with essential buss's........isn't it a little hypocritical or ironic that many will jump on the bandwagon to discredit a VPX system with equivalent backups?
Afterall....stepping back and looking at the big picture of risk....isn't the big fan out front a big potential "single point of failure, all eggs in one basket" item? Which leads me to the third camp...
3. Bare bone architecture w/Modern Backup (Essential Backups are way outdated and not really practical for Glass Panels nowadays). In other words, all we/you need is to essentially go back to Van's supplied wiring diagrams and then utilize the backup batteries (4 hour endurance that will outlast vans standard tanks) for PFD, G5, carry an old Garmin pilot or equivalent GPS and a handheld comm for backup. Bingo??
However, I did see and like the concept of Ironflights electrical method of utilizing a small lightweight 5AH battery that is constantly charging and has all of his buss'e tied together by a multitude of diodes that enables a hands off approach to not having to remember any backup sequence in the heat of the moment. Just flip master batt with backup batt and leave it alone.
Conclusion and question:
The above is my observation, and after thinking about it, I'm leaning towards wiring my craft with a simple basic single buss system that utilizes the current modern unit/LRU designated backup batteries....and possibly using the IBBS or similar to backup ONLY the GTN, Autopilot, & Engine Instruments. KISS
The question is: Is that sufficient backup for a Basic IFR with Pmags machine?...or....would you go a step further and put those items on a completely separate backup fuse buss connected to a backup SD-8 coming off the battery (bypass the master contactor)? But then again.....now I'm back to an essential buss with diode connecting the system.
Given the modern day Glass panel setups and for the gents out there flying with experience on their panels, how would you approach it now if you had to do it all over again?
Sorry if too long but maybe it will help someone in the planning stage.
Thx for the input