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SDS CPI2

As a result of the thermal testing, we're re-designing the coil driver circuit with different components and modifying the board with extra heat sinking capacity. Things were getting a bit hotter than we were comfortable with at max duty cycle.

Some of the new components are already being tested with more to follow on the weekend.

A second prototype board will soon follow. It's an unfortunate delay but this has to be right before production begins.
 
As a result of the thermal testing, we're re-designing the coil driver circuit with different components and modifying the board with extra heat sinking capacity. Things were getting a bit hotter than we were comfortable with at max duty cycle.

Some of the new components are already being tested with more to follow on the weekend.

A second prototype board will soon follow. It's an unfortunate delay but this has to be right before production begins.

DIRFT! Do it right (the) first time.....
 
Running the new circuit today and we're seeing about a third of the temperature at nearly triple the duty cycle as when running the previous test. We're happy with this now and will modify the PCB design to take these new parts. Onwards to further testing next week.
 
Running the new circuit today and we're seeing about a third of the temperature at nearly triple the duty cycle as when running the previous test. We're happy with this now and will modify the PCB design to take these new parts. Onwards to further testing next week.

Pffft. No IR pics.........then it didnt happen! LOL ;)

Nice work Ross. Keep truckin'.
 
Battery Mount

Finally got the prototype backup battery mount done for the CPI2.





Only one ATO fuse holder is shown here. Mounting is via six 10-32 countersunk screws. The top strap will be threaded in 2 places to accept 2 more Adel clamps to hold the battery wires securely.

Total weight is a bit under 3 pounds with the battery.
 
Ross,

Please send me a copy.

I’d also like more details about your blind mount option. Pictures?

The blind mount will dispense with the panel display and you'll have a couple of switches to power up the unit(s). Nothing to really see at this time. We're at least 3 weeks away from machining prototype single and dual board enclosures as we can't do that until the PCB is redesigned.

I'd probably recommend most people who want to blind mount, look at the original CPI, since without the panel display, a lot of the newer features are not available. The CPI is lighter, smaller and less expensive than the CPI2. Plans are to continue to offer both. The CPI appeals to many of the lower hp engine owners (Rotax, Jabiru, VW etc.)

BTW, yesterday Barry completed a severe coil/ board test running at 12,000 rpm for 45 minutes. The new board drivers ran cool but it cooked the coil. I'm guessing few aviation folks will be running at 12K for very long...

Today we were running auto switch over tests and looking at performance at low battery voltages down to around 10V.
 
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Backup Battery Tetsing

We were running backup battery tests with the board and 4 cylinder coil pack running at 2500 rpm powered by the 2.9 AH Powersonic AGM battery we plan to recommend.

Average current draw was 1.18 amps. We ran one coil pack for 1 hr and 15 mins and resting battery voltage was still 11.8V at the end of the test. This was using the regular full coil charge time. We can reduce the charge time about 15% in backup mode to reduce the current draw a bit more with no spark energy issues. Pretty happy with this performance so far.

We'll repeat with 2 coil packs soon.
 
Last night we continued testing of the backup battery. We got 109 minutes of stable run time and will do a slight software change to try to get this to 120 mins. Will repeat that test soon to prove it.

We're tweaking software to the battery charging code today based on measurements from testing yesterday.

The new drive circuits are essentially ice cold running at 2500 rpm. Very happy with that change.
 
We're reviewing the keypad design and that should go to production in about 2 weeks. For the main face we're looking at a dark gray color to hopefully not look out of place on gray or black panels.

There seem to be more gray panels around these days.

Comments on preferences here?
 
We're reviewing the keypad design and that should go to production in about 2 weeks. For the main face we're looking at a dark gray color to hopefully not look out of place on gray or black panels.

There seem to be more gray panels around these days.

Comments on preferences here?

Remember old component hifis/stereos? Black. Not the stupid crazy colors that boom boxes came in.

As all the ladies know, everything goes with basic black. And besides, good guys wear black.

Oh yeah, I almost forgot. Did I mention black?
 
The other option you might want to consider, tho also fraught with handwringing/discussion is leaving it all Aluminum so the buyer can paint to suit.

Of course someone will muck up the display/buttons, so theres that headache......

Maybe you shouldnt have asked! LOL :)
 
I'd like to see the unit match the other avionics on the panel, not the panel itself. That means black to me.

I have a GRT EIS in that strange grey color and it looks odd next to all the rest of the black bezels in that (grey) panel.
 
I'd like to see the unit match the other avionics on the panel, not the panel itself. That means black to me.

I have a GRT EIS in that strange grey color and it looks odd next to all the rest of the black bezels in that (grey) panel.

I have the same. Really dont like that one bit. And its way too big for what it does. I'm gonna take it out of th epanel and hide it behind once I finish 40hr FO. Glad Ross decided on a small head unit for panel CPI2.............
 
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Color

I think color is the lest of concern for a new product that's going in an airplane that has dual ignition!The history of the old product is now not a factor and the new product will be tested by willing groupies to determine its safety and reliability and who knows at what cost?
Bob
 
Just so people are clear here, there is effectively no bezel here like on a G3X and this will have a tactile keypad and LCD as with the current EM-5 and CPI products.

I see what people are saying here, with a bunch of other black bezels, black matches best despite most panels being some shade of gray or white it seems these days.

My partner is not so keen on the black but I do want to listen to what people say on this aspect. Appreciate the input!
 
- Past performance and reliability has been impeccable.
- New design testing has been very transparent. Whenever something doesn?t agree with Ross? very high standard for reliability he admits it to the world and goes back to the drawing board, sometimes repeatedly, until it meets or exceeds his high quality standard. Delays are welcomed.

Then there?s all the other potential benefits:

- Backup battery option
- LOP switch
- Custom MAP
- Trick improved display.
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- ...

SDS CPI2 is not for everyone. It took me quite awhile to get on board and make the commitment. I?m happy to watch and wait until Ross and company gets it completely ready for the market before I complete my install of the remaining CPI2 components. I?m going into this with my eyes wide open with one foot at a time. My first iteration of install will be one slick mag with one CPI2. If all that works as advised, and I have no reason to believe it won?t, I will likely transition to a dual CPI2 system. At least that?s the plan for now.
 
I think color is the lest of concern for a new product that's going in an airplane that has dual ignition!The history of the old product is now not a factor and the new product will be tested by willing groupies to determine its safety and reliability and who knows at what cost?
Bob

I think you're overlooking a few points:

1. The system is packaged in a single box but has 2 separate boards. As such, there is no requirement for the early adopters to run it as a dual ignition during their test and evaluation phase. I intend to run one Pmag for a time before I make the complete switch.

2. There will be some who will jump in with both feet, but that is their right as individuals. That said, those that do will have the knowledge that the CPI2 is a derivative of the legacy CPI which has been flawless in service. The legacy CPI is in turn derived from the EM-5 family of ECU, which has also been flawless in service - delivering decades of reliability that the other manufacturers can only dream of.

3. SDS should be applauded for being proactive in their attempt to satisfy their customer base.

4. Color is irrelevant to the quality of programming and manufacture. No problem locking that down now.
 
Lots of folks have been running dual SDS, P mags, LS, Jeff Rose etc. for years now. If dual EIs don't sit well with some people (and I know they don't) they can opt for a single model which we will also offer.
 
Lots of folks have been running dual SDS, P mags, LS, Jeff Rose etc. for years now. If dual EIs don't sit well with some people (and I know they don't) they can opt for a single model which we will also offer.

I'm one of those single model guys. And a genuine 1940s Bendix designed magneto. Also EFIS and steam gauges, both prominent in the same panel.

I shall live in the past and in the future at the same time!
 
Having flown HUDs and EFIS exclusively for over 25 years I promise you steam gauges are not a good backup for EFIS. You will not remember how to analyze the little white needles in an emergency. Trust me, I tried, numerous times. In the end, I said "you have the lead", and I flew close formation until short final.

The only good backup for EFIS, is more EFIS.

As far as 1 or 2 mags/EI? Up to your comfort level. It is your individual but riding in the plane you built, and you have to be comfortable on that dark and stormy night. For me that is EFI/EI.
 
Having flown HUDs and EFIS exclusively for over 25 years I promise you steam gauges are not a good backup for EFIS. You will not remember how to analyze the little white needles in an emergency. Trust me, I tried, numerous times. In the end, I said "you have the lead", and I flew close formation until short final.

The only good backup for EFIS, is more EFIS.

As far as 1 or 2 mags/EI? Up to your comfort level. It is your individual but riding in the plane you built, and you have to be comfortable on that dark and stormy night. For me that is EFI/EI.

Yes you maybe right. I highly suspect we're on the same path, I'm just 25 yrs behind you. As such I've got planned obsolescence in my panel, that is its built to change out sections (ie subpanels) as I decide its time for a change. I'm a low time guy brought up on all steam all the time, no AP, no GPS. I actually wanted a Dynon system so I could fly six pack until I get used to the airplane, then move to tapes. I ended up buying GRT, and GRT doesnt have that option, so I added steam to cover my uneasiness. And I had space perfectly suited to the gauges; an easy itch to scratch...

As for the dark and stormy night, Ive had electrical systems blink out in the B52 in lightning weather. Different plane, different mission, but all the same, not cool. One of my flight instructors once told me you learn fastest through significant emotional events. Personally, Id rather not learn that way however! LOL
 
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The little standby EFIS that the companies sell are probably priceless. My build is day VFR and an IPAD and Note 8 are my backups.

EFIS takes a very short time to get used to. Maybe a couple of hours.
 
The little standby EFIS that the companies sell are probably priceless. My build is day VFR and an IPAD and Note 8 are my backups.

EFIS takes a very short time to get used to. Maybe a couple of hours.

Gee, I dont know. Do you think I ought to add another one? ;)

2llyjvm.jpg
 
In basic terms, at very high voltages, the OV circuit will pop a device mounted fuse from main bus power. The device will have already switched over automatically to the SDS backup battery at around 15.5 to 16V, wherever we decide that threshold should be to avoid nuisance trips.

Any updates or additional info on the subject of overvoltage? How?s the testing coming?
 
We're doing testing every day (time permitting) trying to see if we can fry anything. Not yet. Near the end of testing when we can sacrifice the prototype boards, we will take things well past the design limits and see what happens.

We're very happy with the OV circuit so far, it's working as designed.

I see in another thread, OV and damage to EI/ EFI systems is being discussed again. This is exactly why we pursued this independent system avenue on the CPI2 as it was a concern to many. We don't care what happens to the rest of the aircraft's electrical system, it could burn up completely. Our circuit will jump in and protect our board, then switch over to a completely independent battery. I believe it will be the only one out there with those attributes.
 
We're doing testing every day (time permitting) trying to see if we can fry anything. Not yet. Near the end of testing when we can sacrifice the prototype boards, we will take things well past the design limits and see what happens.

We're very happy with the OV circuit so far, it's working as designed.

I see in another thread, OV and damage to EI/ EFI systems is being discussed again. This is exactly why we pursued this independent system avenue on the CPI2 as it was a concern to many. We don't care what happens to the rest of the aircraft's electrical system, it could burn up completely. Our circuit will jump in and protect our board, then switch over to a completely independent battery. I believe it will be the only one out there with those attributes.


Great news. Thanks Ross.
 
Have been tweaking software mostly this week. Next week will involve mostly production of EM-5 orders as Barry heads out the week after for a well deserved and very needed vacation for 5 days in a warm place.

Our winter is hanging on here, still snowing which is very unusual at this time of year. That's not helping to speed the project along. I'd like to be running the system on our O-200 here but need warmer weather for that.
 
Barry was able to lick the last few software annoyances on Sunday so we'll be able to carry on with the second proto board production later this week to start testing of 2 boards talking together.
 
Engine Testing?

Some people have asked how testing is coming along on the CPI2. Bench testing and tweaking continues but no engine testing has taken place yet.

The winter here has been unusually long this year and it's still cold and foggy today, snowed a bunch more yesterday. They say tomorrow it will really break but we've heard that several times in the last month.

As soon as we get a real break, we'll have the CPI2 running on our O-200 and post some videos and results. Unfortunately can't do much about mother nature in this case.
 
Update

Barry has been solving a couple more odd issues with the battery switching circuits last week and this week, uncovered by bench testing when running the coils and interrupting power. One was taken care of with some new code, another required another component to be added.

The OV protection will be tested tomorrow and if that goes well, it will come off the bench on Monday.

This week was crazy busy with orders but the weather is finally good so our plan is to get the CPI2 prototype on the engine test stand next week to begin the running tests and battery switch over testing on an actual running engine.

Some issues have been really time consuming to fix on this device but we're just knocking them down one at at time.

Sorry for the long wait.
 
Progress

Bit of a milestone today. We finally ran our O-200 test engine with the CPI-2 providing the spark on the top plugs and an EM-5 running the bottom plugs plus injectors.

We got to test the battery switch over circuit by draining down the primary battery to below 10.2V and having the CPI-2 automatically switch over to the backup. Engine did not appear to skip a beat. We tried the test about 5 times by momentarily (1-2 seconds) touching a lead to the starting battery to bring the primary CPI-2 battery above the switch threshold voltage and then let it drain down again and switch.

More testing to do but it worked as designed so far.

We did have knock indication where the knock retard was zeroed. Believe that is a software thing so will be looking to fix that before the next engine runs.

I shot some video, will try to post that later today. Conditions were not so good to run outside with gusty winds and a bit of rain but we had to run the thing. There have been too many delays.
 
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Did some more running today on the engine testing the battery switchover circuits, pulling battery leads right off and connecting again, trying to induce spikes and oscillations in the circuit right near the switching threshold. Perfectly smooth transitions. Seems the extra weeks of hard work has exorcised the demons which had been plaguing us during bench testing.

Next step is to incorporate the many changes made to the first prototype board and do a couple more new ones to test before production boards are made.

We'll try to get that in process at the end of the first week in June along with the keypads. That might be slow though as we have multiple EM-5 and CPI orders to work on next week. The summer months are usually a bit slower but looks like we'll be slammed in June at least.

We appreciate all the support!
 
Is the battery switchover circuit testable? If so, how?

Only if you were to take the primary battery voltage down below the switching threshold. There are condition LEDs to tell you which battery is feeding the unit and one of the gauge modes shows primary and backup battery voltage on the same screen so you can check battery charge state.

The unit has a charging circuit inside to keep the backup battery topped up.
 
Excellent.

Can the CPI2 Be manually switched to select one battery over the other?

Does it matter what battery chemistry one uses?

Can battery chemistry be mixed, for example, AGM lead acid with Lithium?
 
At this time, it's not designed to be manually switched but should be possible to do that in software. The present strategy is to run off the main bus battery until voltage drops too far to be useful and then auto switch to the small backup. People were asking for a fully automatic system so that's what we tried to deliver here (and what took so long to develop and work out the bugs).

You'll have a visual flashing display indication when main bus voltage drops below 12V or so to tell you that the alternator is offline. You can also have a split screen showing both battery voltages and an arrow icon showing which battery is currently feeding the CPI2 and multi colored LEDs.



Screenshot from the test video

Battery chemistry may matter somewhat where the switching thresholds occur. We'll probably make these user programmable in setup mode once we examine more technical data from the lithium battery manufacturers. Mixed chemistry shouldn't present any issues with individually settable switch points. The CPI2 constantly monitors both.

We can do other things in software to reduce coil charge times (thus current draw) to extend battery run times as voltage gets down to certain levels if we think that is useful.
 
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Outstanding Ross.

I?m an advocate of fully automatic switching.

The display looks good. Font size and color looks right. The flashing display idea for a visual low voltage alert seems right.

Did you build In an aural low voltage alert as well?

Any idea on cost yet?

Are aux battery trays available yet?
 
Outstanding Ross.

I?m an advocate of fully automatic switching.

The display looks good. Font size and color looks right. The flashing display idea for a visual low voltage alert seems right.

Did you build In an aural low voltage alert as well?

Any idea on cost yet?

Are aux battery trays available yet?

I believe Barry has the parts on the board for an aural output signal. He did some testing in the winter on that.

No idea on cost yet. The R&D costs are about triple what I projected. We'll have to hope to make that up in volume...

The trays have slid down the machining priority list many times now as capacity is used to make in-demand parts for the EM-5 kits, valve covers and some other new secret parts.

I handed Trevor a new parts list on Tuesday. Last item there is scheduled to run in mid June. I should be able to get the battery boxes finally machined and anodized by early July then.
 
Barry got lots of work done on the next board design incorporating all the changes learned from testing over the last couple months. We've just added some components for voltage measurement when using a lithium battery as primary power as well.

There is no more room on the board to fit any more stuff so he's close to getting a pre-production set of boards made and loaded to confirm everything is good before we go to full production.

Light at the end of the tunnel finally- we think...
 
2nd proto board design will go out to the board maker Thursday it looks like.

We were compiling the parts list for machine loading and working on the keypad design a bit today, waiting for a final component to come in tomorrow to finish things off.
 
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Load Dump Test

We completed some load dump tests today to determine reaction time for the OV circuit. Loaded the battery up to 150 amps with the alternator charging and released the load quickly. Max voltage spike was only around 11 volts on the scope and of very short duration- less than .5 milliseconds. We were expecting something a lot more intense.

This was using an IR alternator which is all we have around the shop. I suppose some of the externally regulated alternators may not perform the same way.
 
We completed some load dump tests today to determine reaction time for the OV circuit. Loaded the battery up to 150 amps with the alternator charging and released the load quickly. Max voltage spike was only around 11 volts on the scope and of very short duration- less than .5 milliseconds. We were expecting something a lot more intense.

This was using an IR alternator which is all we have around the shop. I suppose some of the externally regulated alternators may not perform the same way.

Probably need to rework the test setup.

There are world-wide automotive standards. The immunity requirements are a lot higher than an 11 volts and 4ms. Examples...

This list dates back to 1991:

14292f7.jpg


The latest standards require hitting the system with 10 pulses of 79 to 101 volts at one minute intervals, as suppression device capability tends to change with heating:

https://www.vishay.com/docs/49748/49748.pdf

There are smart guys out there discussing how best to simulate load dump:

http://www.emtest.com/bindata/bindata/publications/autoEMC_paper_loaddump_may06_rev03.pdf
 
Thanks for the info Dan. I'll forward that to Barry for review and maybe do some further testing.

Even with the scope scale expanded out, the spikes were virtually a single line up/ down. We did over 150 load/unload pulses. This followed some bench testing with higher voltages applied.

The alternator control was super fast and the battery seemed to soak up anything that we'd consider remotely dangerous.

Our main concern was in preventing nuisance trips of the OV circuit.

The components exposed in this circuit are all rated for over 125V but the spikes were so short to be of no concern- micro seconds in this case. The CPI2 will just switch to the backup isolated power source in the worst case. The circuits have both component level and CPU monitoring and intervention. Most systems and designs don't have an isolated power source to switch to.

In the past, we've done load dump testing on the EM-X several times as each new ECU design came out, never saw any issues and we don't see failures caused by these spikes.

Remember, we have nearly 10,000 controllers out there with millions of hours collectively in all types of vehicles and environments. There have been plenty of stupid things done to them in that time, odd electrical failures and poor installation practices.

We consider testing important, which is why we're doing them again with this design. We also consider the vast real-world experience significant.
 
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