SDS CDI vs Pmag

[Chkaharyer99]

Originally Posted by rv6ejguy

Should we keep the green then?

No. Please no.

Can you identify and explain the differences in function between the EM-5 using the round LCD for electronic Ignition only vs going with SDS gen 2 CPI.

For example, will the new gen 2 CPI be smaller then the EM-5 round LCD controller?

I sincerely appreciate that SDS is continually improving and updating their products.

[rv6ejguy]

Originally Posted by Chkaharyer99

No. Please no.

Can you identify and explain the differences in function between the EM-5 using the round LCD for electronic Ignition only vs going with SDS gen 2 CPI.

For example, will the new gen 2 CPI be smaller then the EM-5 round LCD controller?

I sincerely appreciate that SDS is continually improving and updating their products.

There is not much difference in function between having the full EM-5 ECU control ignition and the CPI. Cost is roughly $800 more with the dual EM-5 setup off the top of my head. The EM-5 way would give you a future upgrade path to EFI if you were interested in going that direction, the CPI does not give you that choice.

Yes, the CPI2 face will be a bit smaller than the current 3 1/8 round EM-5 programmer.

The market is asking for these improvements and re-packaging. If we keep making the same old stuff, we'll be left behind in this field or lose market share. I think our key to success is to give the people what they want. Too many other companies don't listen and give you what they think you should have and continue to offer 5 or even 10 year old products with few or any useful improvements.

[Canadian_JOY]

Originally Posted by rv6ejguy

Too many other companies don't listen and give you what they think you should have and continue to offer 5 or even 10 year old products with few or any useful improvements.

I think Ross' active participation in this discussion form is a strong indictor of how closely SDS listens to its customers. Add to that Ross' ability to respond to questions via email, often within minutes, and a potential customer gets the feeling that he's dealing with a company that actually cares. We are very fortunate in this little corner of the aviation industry to have access to a supplier of such high caliber. (I say this without yet being a customer - years of Ross' posts here reveal he is as straight a shooter as they come.)

[Chkaharyer99]

Thanks Ross.

I really like the EM-5/LCD controller solution as it would allow me to start out with SDS EI and one mag and progress from there to a full SDS compliment of 2 SDS EI's and FI.

I know I'm getting off topic on the FI speak so I'll stop there.

Thanks again !

[tspear]

Originally Posted by Canadian_JOY

I think Ross' active participation in this discussion form is a strong indictor of how closely SDS listens to its customers. Add to that Ross' ability to respond to questions via email, often within minutes, and a potential customer gets the feeling that he's dealing with a company that actually cares. We are very fortunate in this little corner of the aviation industry to have access to a supplier of such high caliber. (I say this without yet being a customer - years of Ross' posts here reveal he is as straight a shooter as they come.)

I agree, I am also not a customer. However Ross has explained multiple ignition items for me, in way even a dumb programmer can follow.

Tim

[Bill Boyd]

"If experimenting with larger coiltime settings, rev the engine in neutral and monitor ignition current. "

Can I leave the plane in gear and just hold the clutch in?

[rv6ejguy]

Originally Posted by Bill Boyd

"If experimenting with larger coiltime settings, rev the engine in neutral and monitor ignition current. "

Can I leave the plane in gear and just hold the clutch in?

It's not good to experiment seat of the pants with coil charging times. For normal aircraft systems we charge to get them within about 95% saturation to minimize heat in the coil. This is plenty for the low specific outputs present here. We typically only use two coil types on aircraft engines but if we had to use an unusual coil in the future, we're all set to later alter the charge times.

For the Reno guys, we push the charge time out to get 100% since they are short duration races. Some folks may be pushing to 90 inches this year in Sport Class and that requires every joule of coil energy to light off such dense mixtures.

[czechsix]

Originally Posted by rv6ejguy

Preliminary design work on the next gen CPI will begin on Sept. 1

Looking for customer feedback on any additional features people might want.

One thing I'm interested in (when contemplating dual electronic ignition) is robust protection against any common cause taking out both of them. My RV-8A was hit by lightning a few years back. The dual Lightspeeds ignition units were unscathed (the voltage regulator for the alternator was fried). Any idea how the SDS CPI would handle a lightning strike?

Another thing on my radar is new battery technology like EarthX. The weight savings are tempting and doubtless they are the way of the future, but all of their self-monitoring features introduce possible failure modes that a simple lead acid battery doesn't have (such as shutting itself off due to perceived internal fault, overvoltage, etc). If the battery disconnects itself while the alternator is running then everything on the bus gets hit with a pretty good surge, which some electronic devices can handle and others cannot depending on how robust their design is.

Good electrical system design mitigates most of my concerns but it would still add some peace of mind knowing that my electronic ignition units have been designed/tested to handle potential anomalies within reason. Reference DO-160 standards which most certified equipment are developed to meet...I have seen several documented cases of lightning strikes and overvoltage conditions taking out the 'experimental' stuff in the panel while leaving the TSO'd radios/GPS/transponder unscathed.

Oh and +1 for the more aesthetically pleasing user interface that will look nice with the G3X panel in my -14.

[6 Gun]

Ross in the new model put a 9v back up battery.
Bob

[rv6ejguy]

We finished some engine testing on the stand yesterday which decided some of the design layout of the CPI2. This should speed things along as we won't have to add the extra components now.

The case here about the lithium battery shutting itself off a month or so ago due to alternator overvoltage and then frying some expensive electronics as a result of even higher surge voltage leads us to recommend having electronic crowbar protection when using these batteries with our electronics. We will look at doing some sort of internal voltage limiting to protect the device from serious OV and have it reboot after the OV condition is removed.

We are a small company and the testing required to pass DO 160/178 standards would probably quadruple/ quintuple the product cost in the end due to the small production volumes. It would add many months to the release date as well. This would in turn reduce sales to nil making the whole process a waste of time. Fine for companies with the financial resources to do this and sell to the certified market, but not for us. Most Experimental folks are already flying around with a panel full of equipment which has not been tested to these standards.

We do our usual over voltage tests, low and high temperature tests and vibration is no concern with our components. I suppose we could try some crude "lightning tests" with an ignition coil arcing to the CPI case. Would be interesting to see if the system would reset and keep going or not.

We do have some new test equipment now which we didn't have a couple years ago. This will aid in testing the software and hardware faster and better than before.

All good food for thought. Thanks for your comments.