Help Vertical Power Develop New Product

[MCA]

Peter, you'll see earlier in the thread that we are proposing to include a ground block with the system The PPS itself does not handle grounds, which is what I suspect you're asking about.

Thanks for the feedback so far. Keep it coming!

[f1rocket]

Originally Posted by Mike S

Ah, the lure of electronic wizardry

Cost, weight, complexity, additional failure points, difficulty in troubleshooting problems..........

Give me a simple old key switch.

Which is the most likely device to fail in the ignition circuit!!

I agree with simplicity, but sometimes the old mechanical stuff can't provide the functionality to fit the situation. My Rocket didn't have a key switch either (which is easily hot wired BTW) so anyone could hop in, flick the switches, and start the airplane.

If you park outside a lot (which I do not) then a hidden "kill" mechanism might be desirable as long as it doesn't KILL YOU!

[Mike S]

Originally Posted by f1rocket

Which is the most likely device to fail in the ignition circuit!!

True, but it is easy to diagnose, easy to replace, easy to find a replacement, and if needed it is an easy thing to bypass in the field so you can fly home.

Electronic "wizardry-in-a-box" from a single vendor on the other hand

[BDFLYER]

Any chance I am not the only one with a need for a GPU connection? I would really like to be able run the systems on the ground without having to turn on the engine or run solely on battery (such as with programming the flight systems...).

[Peter Autenried]

Other features to include:

1. Ammeter to measure Current in circuit
2. Volt meter
3. Battery charging management system for light-weight Li batteries

[BDFLYER]

Hi Peter,

I saw this note form your post;

" 3. Battery charging management system for light-weight Li batteries"

Interesting - I wonder if this function should be part of the Li subsystem, though. That said, are you looking at any specific Li solution? This is of interest on my end.

[southtarnation]

Originally Posted by BDFLYER

Hi Peter,

I saw this note form your post;

" 3. Battery charging management system for light-weight Li batteries"

Interesting - I wonder if this function should be part of the Li subsystem, though. That said, are you looking at any specific Li solution? This is of interest on my end.

I would like that feature. I just got a Sorai lfx18 battery and am reading about the charger requirements.

[Peter Autenried]

I was thinking to use an 12 Cell Aerovoltz Lithium Iron Phosphate battery or similar

http://www.ballisticparts.com/products/products.php

and have the PPS manage the charging or discharging of the individual cells of the Li-Phosphate batteries during flight.

[MCA]

OK, back to the Primary Power System.

We recently had several proto printed circuit boards (PCBs) fabricated to do initial testing of certain circuits and to see how the solid-state switches perform under load.

Below is a picture of the PCB in a temp chamber with a few of the solid-state switches mounted and some associated circuitry. You can see a large cable coming in and going out to several large batteries mounted outside the temp chamber. Externally, we?re simulating loads in the 250+ amp range and measuring circuit temperatures under various loads and various air temperatures ranging from -40 deg C up to 100 deg C. We?ll extend that range as we learn more.



We contacted several starter manufacturers for guidelines. They recommend a maximum of 10 seconds to run the starter with a few minutes cool down time. So we are targeting 20 seconds+ as a design goal to run the starter circuit at 250+ amps.

The electronic circuit breakers (which act as switches and breakers together) for the alternator B-lead and the main bus are designed for continuous operation at 70+ amps. We?ll get to those soon and post here.

[MCA]

Things have been pretty busy, so sorry about not providing more recent updates.

We have developed the circuitry to simulate a shunt output. This allows you to connect the ammeter (electrical current readings) inputs on your EFIS directly to the PPS. Now we are working on testing it across a wide range of conditions to determine the accuracy of the readings.

Here's a picture of Josh's test rig to test different circuits and failure conditions.



We've also decided to defer the keypad and/or key fob idea indefinitely. This was initially part of the PPS, then we realized it could be a stand-alone system. Therefore it is not in the critical path of developing the PPS. Plus, there are automotive alternatives out there for ignition security.