| The Legacy plans show a 35 amp breaker instead of a 50amp. On a side note: I fried the casing off a 22gauge wire about 13" long and its amazing how much smoke it created. I would not have wanted to see that in flight.
Bryan On Tue, May 26, 2009 at 1:22 PM, John Cooper <snopercod@citcom.net> wrote:
Good comments so far by several responders. My personal additions:
1. A 50A circuit breaker specified in the plans will in no way protect your hydraulic pump from burning up should the rotor lock up, neither will it protect your #10 pump wiring from burning up in the event of a fault. This error by the factory dates back to the very first kit in 1986(?), and AFAIK, Lancair has never corrected it. The Oildyne pump draws maybe ~15 Amps when the gear are in motion, which spikes up to ~30 Amps just before the pressure switch stops the pump. A 50 Amp circuit breaker will take roughly 3 minutes to trip with 100 Amps flowing through it. Think about that.
If you insist on using a circuit breaker, 30A would be better, but still won't protect you from smoke in the cockpit should your pump lock up. (A 30A or 40A Maxi-Fuse offers better protection.)
2. Yes, connect the control power circuit breaker downstream of the main circuit breaker for the hydraulic pump. That way, the relays can't stay energized when the main CB (or fuse) is open.
3. I recommend high-reliability 75A Bosch Relays for the hydraulic pump, not the crap that the factory provided. (see details and part numbers posted here sometime during the last year).
4. Yes, use the back-to-back diodes to feed your "gear transition light". (See the schematic I posted here a few months ago). I used a red/green LED which shows red when the hydraulic pump is running in either direction, and green when the nose gear door is closed.
5. Lance was a true genius when it came to aerodynamics, aesthetics, and business, but he didn't know diddly about electricity.
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