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Plane power standby alternator

pierre smith

pierre smith

Well Known Member
I'd like the Plane power 13.6 volt standby alternator for my -10's vacuum pad mount but the $767 price (Aircraft Spruce) is hard to swallow.

Do any of you guys know of a more reasonable source or alternative option?

Thanks,
 
I should add, by the time you get the external regulator etc... for the B&C, it is probably the same money as the PP internally regulated unit.
 
I installed the B&C SD-8 as a backup. $545 comes with the regulator.

Not exactly an alternator, rather a "dynamo" (fixed magnets). Mounts on the vacuum pad. Mine works well.

Outputs 8 amps.
 
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airguy said:
Yep, this is the one to have.
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Depends on what your need is.
Pretty easy to do the math for your essential bus. Keep in mind, this is a back up. You need enough battery plus subsequent back up power to get you safely to a suitable field for repair, not to get you to your destination. If you are considering the larger units, make sure it works physically - oil filter, motor mount, etc...
 
Just as a data point for future resders, I have the PlanePower FS1-14 mounted on my IO-540. There are no mounting issues although 1 of the 4 mounting nuts is a rear bear to get to. This thing puts out 30 amps so if lose my 70 amp primary I don't even have to load shed.
 
I too have the B and C alternator. It's been a great performer for me. Also as its been been mentioned, one of the nuts is hard to reach. I had to take off the mag to make it easier when I just upgraded to the B and C oil filter adapter.
 
cderk said:
At some point, I will need to be shopping for stuff like this. Am curious to know why some prefer the B&C over the PP unit.

Thanks
charlie
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Chevy - Ford. Specifically the B&C standby alternators are externally regulated (so more pieces parts and a bit more to the install with extra wiring) while the PP FS1 is internally regulated. Also B&C were the first in the game.
 
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The B&C alternators are balanced to a finer degree/higher RPM, and have a solid track record in terms of hours of trouble free service. If you have been following the various forums there have been more than one or two reports of broken armature windings at low hours, some even while in the first 25 hours, with the other brands.

Do your homework and search the various threads for alternator issues.
 
financial and W&B math?

JonJay said:
Depends on what your need is.
Pretty easy to do the math for your essential bus. Keep in mind, this is a back up. You need enough battery plus subsequent back up power to get you safely to a suitable field for repair, not to get you to your destination. If you are considering the larger units, make sure it works physically - oil filter, motor mount, etc...
Click to expand...

Curious what you all think of a dual battery system for endurance bus power vs a second alternator or dynamo - now that Lithium Iron batteries are coming into some measure of acceptance in "OBAM" aircraft. Seems like the weight of a Shiori or EarthEx Li battery with significant amp-hour capacity is less and the cost is less, too, depending on exact models of batteries and alternators under discussion. Less HP being sapped from the engine to keep a second battery topped off than to continuously spin a gear-driven second alternator, I would guess.

Plus, with two batteries, if sized identically, one could do the Nuckolls battery rotation-replacement program and keep a fresh cranking battery on line at all times and a tested-good, older battery on standby duty for dark stormy night scenarios.

-Bill B
 
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Good question

I think having a battery instead of a second alternator might depend upon what are your mission requirements. If you happen to be outbound on a long trip, like a vacation, and the primary alternator fails, you are going to have to get it fixed. The standby alternator, especially the higher capacity one, will actually allow the complete completion of the trip and allow for the repairs while back at home base.
We could aslo argue the other side of the coin--- what if the battery fails? Clearly, the second alternator probably isn't going to do much good. However, complete battery failures, while not unheard of, seem to be less than alternator failures. Battery technology seems pretty robust these days, as does the B&C alternator product line.
I hate to jinx it by making this statement, but the only alternator failure I've ever had was on my original RV-4 with a GM alternator. Been using B&C ever since without any problems. That's over 4000 flight hours across 5 different RV's all wired the same way.

Vic
 
cderk said:
At some point, I will need to be shopping for stuff like this. Am curious to know why some prefer the B&C over the PP unit.

Thanks
charlie
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External Regulation. B&C puts the sensitive electronics in the cockpit away from the heat. PP puts them right on the back of the alternator.

Not saying one is better or worse, just what I chose and why.
 
vic syracuse said:
I think having a battery instead of a second alternator might depend upon what are your mission requirements. If you happen to be outbound on a long trip, like a vacation, and the primary alternator fails, you are going to have to get it fixed. The standby alternator, especially the higher capacity one, will actually allow the complete completion of the trip and allow for the repairs while back at home base.
We could aslo argue the other side of the coin--- what if the battery fails? Clearly, the second alternator probably isn't going to do much good. However, complete battery failures, while not unheard of, seem to be less than alternator failures. Battery technology seems pretty robust these days, as does the B&C alternator product line.
I hate to jinx it by making this statement, but the only alternator failure I've ever had was on my original RV-4 with a GM alternator. Been using B&C ever since without any problems. That's over 4000 flight hours across 5 different RV's all wired the same way.

Vic
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Assuming you don't jump start a dead battery and fly away, a battery itself failing is unlikely. Much more likely to fail are the things you have in the system connecting the battery to what you want. So four batteries and four alternators are of little value if you have them going to one master solenoid that decides one day to fail open. Same goes for an "Avionics Master" that fails open.

My point - look beyond the system components to system design. At some point something will fail. Look for the common failure points, either a component, a common buss connection or the single ground lug on the one battery. If this fails will your system able to degrade gracefully (e.g. loose COMM #1 but keep COMM #2) and then be reconfigurable to restore the full panel? If the answer is no, then you may wish to look for other approaches.

Carl
 
Good point

Carl has a great point. I have only seen one master solenoid failure, and that was in a customer's airplane. He happened to be flying by when it happened, and was able to land, I replaced it, and he was on his way. However, I always install a solenoid bypass switch on the panel just in case. :)

Vic
 
vic syracuse said:
If you happen to be outbound on a long trip, like a vacation, and the primary alternator fails, you are going to have to get it fixed. The standby alternator, especially the higher capacity one, will actually allow the complete completion of the trip and allow for the repairs while back at home base.
Vic
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Vic - You have the knowledge, experience, and judgment to know if you could safely complete your trip on the back up or not. Not everybody does....

A couple things to remember. The larger the unit the more weight. Not a big deal, but a couple more pounds is just that. Even less of a deal for the 10's and 14's than for others.
Also, check the specs on these gear driver alternators. The B&C as an example is rated for max. output at 3500 rpm. Anybody know what the gear ratio is? Are these things spinning up there at cruise rpms? Curious....
 
JonJay said:
Vic - You have the knowledge, experience, and judgment to know if you could safely complete your trip on the back up or not. Not everybody does....

A couple things to remember. The larger the unit the more weight. Not a big deal, but a couple more pounds is just that. Even less of a deal for the 10's and 14's than for others.
Also, check the specs on these gear driver alternators. The B&C as an example is rated for max. output at 3500 rpm. Anybody know what the gear ratio is? Are these things spinning up there at cruise rpms? Curious....
Click to expand...

The ones that fit on the vacuum pad are driven at 1.3x crankshaft speed, so 2400 rpm cruise would be 3120 alternator rpm. 2700 prop redline would be 3510 alternator rpm.

I chose the 20-amp standby alternator due to my lack of an engine-driven fuel pump, and the requirement for excited electrons to push my electric fuel pumps. Catastrophic battery failures are much less common than dropping an alternator, I felt it was a good decision to go with a single battery and dual alternators. YMMV.
 
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JonJay said:
Vic - You have the knowledge, experience, and judgment to know if you could safely complete your trip on the back up or not. Not everybody does....
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I hear you, and I am doing my best to help pass that knowledge and experience along. :)

VIc
 
Done.

Well, the Plane power is in and works well. Ray installed it after lunch. I needed something quickly because Ray is headed for Sebring and the UL booth tonight.

We leave for Eleuthera on Sunday morning.

Thanks for the help guys,
 
Shear?

Pierre Do you know if the PlanePower 30A 13.6V Alt have a shear shaft
like the B&C 20/30 Amp for the Vac Pad hookup? Just checking.
John
 
??

Flyingleap said:
Pierre Do you know if the PlanePower 30A 13.6V Alt have a shear shaft
like the B&C 20/30 Amp for the Vac Pad hookup? Just checking.
John
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I did not know that..
Since it turns a lot slower than the primary, it needs to be tested above 2,000 RPM. Run the engine up to 2050 or so and turn off the primary alternator. You'll see the voltage drop down to 13.6, meaning that the standby has kicked in...easy peasy.

Best,
 
I can actually see mine putting out decent current at 1700 during a normal runup, enough to verify function anyway. I pull my primary alternator offline completely, let the voltage sag to stable on the battery alone, then bring the standby online and look for a charging rate through my Dynon shunt.
 
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