flyrotary@lancaironline.net Mailing List Archive

Charlie,

My amp numbers may be a bit higher due to the Holley billet fuel pump (p/n 12-700). It pumps like Niagra Falls and likely draws more amps that the smaller RWS pump. Once in cruise I could switch to the RWS pump, but I don't know how much amperage it would save, if any.

Also, there are a number of non-flight-essential items I could turn off to reduce the load in a pinch.

This is one reason why I went with a two alternator system, so that I'll hopefully never have to find out how long the battery will last without an alternator feeding it juice.

Mark

On Thu, Jul 3, 2014 at 4:12 PM, Charlie England <flyrotary@lancaironline.net> wrote:

Thanks for the info & the panel pic. Must be nice to have that much panel height. :-)

It's looking like the real killer is the fuel pump. If Dave's seen as low as 4 amps, that might mean that a turbine style pump with PWM controller would be worth pursuing. Yet another task to keep me from ever finishing....

Charlie

On 7/3/2014 12:53 PM, Mark Steitle wrote:

Charlie,

My 3-rotor, along with typical electrical devices running, needs 36 amps. This includes EC-2, EM-2, 6 fuel injectors, 6 ignition coils, 1 fuel pump, EFIS, auto-pilot, NavCom, Xpndr, strobes, and M/T Electric prop controller. Not sure what it needs just to keep the fan turning. My guess is that I could probably cut that figure in half by turning off the xpndr, radio, strobes, EFIS, and trailing coils. (It would be very interesting trying to fly without the EFIS.)

Thanks,

Mark

On Tue, Jul 1, 2014 at 7:19 PM, steve Izett <flyrotary@lancaironline.net> wrote:

Hi Charlie

I think these are in the ball park but not measured under flying conditions only idle.

ENGINE

EC2                                          .3

EM3                                         .5

COILS (D585) 5

INJECTORS (Renesis) 2

FUEL PRESSURE PUMP x 1 8.4

FUEL TRANSFER PUMP x 1 1.6

O2 SENSOR                             0.6

Total Engine                            18.4

Steve Izett

On 2 Jul 2014, at 5:08 am, Charlie England <flyrotary@lancaironline.net> wrote:

Has anyone with an ammeter installed measured their engine's actual current draw (controller, injectors, plugs, fuel pump) with everything but the engine shut down, and the alternator offline? IIRC, Bernie Kerr once did a battery duration test & discontinued after ~40 minutes, but I don't recall seeing any actual current measurements.

Thanks,

Charlie