Reference: GTX 335 w/GPS Installation Guidance Rev. 1 Page 3-13 Paragraph 3.13.1 Circuit Protection and Power Distribution
A friend of mine is building a Zenith 750 STOL VFR airplane. I tried to convince him to keep his electrical system simple with just a main power bus, no avionics bus. But he pointed out that the GTX 335 installation manual requires an avionics bus. He thinks that the GTX 335 is vulnerable to voltage sag during engine start. That is not true is it? Why is Garmin telling builders to install an avionics bus?
That same paragraph states that the GTX 335 MUST be protected by a readily-accessible resettable circuit breaker. Why does Garmin think the transponder circuit breaker will trip? What is wrong with using a fuse? Why reset the transponder circuit breaker and take a chance on filling the cockpit with smoke? Wouldn't it be better to save electrical troubleshooting for when safely on the ground?
I suggest that Paragraph 3.13.1 be deleted. The only useful information it contains is the recommendation to supply each electrical load with its own unique overcurrent protection. I also suggest that the term "Avionics Bus" be removed from Figure B-1 and Figure B-4. Thanks
A friend of mine is building a Zenith 750 STOL VFR airplane. I tried to convince him to keep his electrical system simple with just a main power bus, no avionics bus. But he pointed out that the GTX 335 installation manual requires an avionics bus. He thinks that the GTX 335 is vulnerable to voltage sag during engine start. That is not true is it? Why is Garmin telling builders to install an avionics bus?
That same paragraph states that the GTX 335 MUST be protected by a readily-accessible resettable circuit breaker. Why does Garmin think the transponder circuit breaker will trip? What is wrong with using a fuse? Why reset the transponder circuit breaker and take a chance on filling the cockpit with smoke? Wouldn't it be better to save electrical troubleshooting for when safely on the ground?
I suggest that Paragraph 3.13.1 be deleted. The only useful information it contains is the recommendation to supply each electrical load with its own unique overcurrent protection. I also suggest that the term "Avionics Bus" be removed from Figure B-1 and Figure B-4. Thanks
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