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SDS CDI vs Pmag

Chkaharyer99 said:
Can you describe what will be needed for a SDS CPI2 (EI) user to add SDS FI?
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The CPI is designed to do only ignition duties so if your plan is to later add the fuel injection bits, best to buy the EM-5 ECU(s) from the start. We can offer you just the parts needed to do ignition initially and you can purchase the rest of the fuel injection kit parts later. This saves buying things twice and spreads out the hurt on your wallet and downtime a bit. The EM-5 solution is a bit more expensive than the CPI initially but a number of people have opted to go this way.

Sometimes the budget manager (spouse) may not release all the funds for the full-up EFI/EI all at once. ;)

We find many folks want the EI but prefer to keep their mechanical FI or carb, hence the main reason for the CPI. It's the lowest cost, production Experimental EI system available today for Lycomings.
 
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Chkaharyer99 said:
Can you describe what will be needed for a SDS CPI2 (EI) user to add SDS FI?
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If your true intent is to go EFI, then Ross' advice is sound: go with the EM-5 and run ignition only for a while. That said, I jumped from CPI to the EM-5 and can say that the coils, hall sensor and much of the wiring is the same. Essentially, all you replace is the CPI brain box. Considering the popularity of the system, there is a ready second hand market for these. You shouldnt get hurt financially going either way.
 
Brantel said:
....

1. That being said, if I were not already in bed with the Pmag, I may have gone a different direction if I were starting out fresh today.

2. The SDS CPI would be very high on my list....

3. Pros: Complete monitoring and control of the ignition from cockpit (without any 3rd party add on box)....

4. Cons: ....the user must provide some sort of backup power scheme.
....
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1. Ditto.

2. Ditto.

3. For me, this is a negative. I don't want to have to think or that while flying. At times there's quite enough to think about anyway, and for me, this is totally out of my comfort zone.

5. Ditto, this is a very large negative for me. I'm trying to keep my RV-3B project somewhat simple, relatively speaking.

Dave
 
We enter an appropriate timing curve based on fuel used and CR prior to shipping each unit. You don't need to monitor or fiddle with anything.

The CPI2 will address backup power with the new option we're designing to remove that burden for those who desire it.
 
David Paule said:
...3. For me, this is a negative. I don't want to have to think or that while flying. At times there's quite enough to think about anyway, and for me, this is totally out of my comfort zone.

5. Ditto, this is a very large negative for me. I'm trying to keep my RV-3B project somewhat simple, relatively speaking...
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The ability to access your ignition program does not translate to a need to access your program. It is a "set and forget" system. The display is simply a handy form of situational awareness. If it makes you feel better, there is no reason why you can't stuff the CPU under the panel after its programmed.

For a"simple" airplane (I'm guessing no IFR), it's pretty easy to consider the "primary" power source the alternator, and the "backup" as the ships battery.
Not everyone needs "Mars flight" levels of redundancy. Evaluate your needs and go from there.
 
Toobuilder said:
If your true intent is to go EFI, then Ross' advice is sound: go with the EM-5 and run ignition only for a while. That said, I jumped from CPI to the EM-5 and can say that the coils, hall sensor and much of the wiring is the same. Essentially, all you replace is the CPI brain box. Considering the popularity of the system, there is a ready second hand market for these. You shouldnt get hurt financially going either way.
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Thanks Michael. I am fully committed to SDS CPI2 EI but feel the move to SDS EFI might be more work than I'm prepared to take on. Two big projects for an EFI system that stick out in my mind are 1) adding fuel return lines to my tanks and 2) re-plumbing my fuel selector valve. But, having and not using the EFI option while I enjoy the benefits of SDS EI is very tempting. I don't want to regret the decision of not buying the full system. The secondary market you mentioned isn't something I had considered. Maybe because I'm such a poor salesman. A key ingredient to this decision for me is what Ross and his team are doing with the new CPI2, most notably, the addition of a backup/auxiliary battery. I'm not sure the EFI system is being considered for the backup battery option revision and I'm hesitant to ask, this being a thread about SDS CDI vs Pmag (EI).

The reports about SDS systems by you, Celeb, Dave and others has served to give me perspective and understanding. Thanks for your insight.
 
We do see some people want a vendor designed backup battery system for the EFI as well but at the same time, many others are designing complicated systems for this purpose. We won't be shipping big 18 AH batteries all over the place but can possibly provide switch gear and schematics for those who wish to use our solution.
 
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So far this week, we have most parts of the battery switch over circuit working well in a breadboard form. Starting to look at the general layout of the PCB components now to fit in the new case design.

We're working with some new vendors on the keypad side as our usual one has jacked up their rates for small quantities. That's going to end a 15 year relationship with them.

Working on a switch gear kit to replace the standard, old school mag switch for those doing a new build. This will save some more money for these folks.
 
rv6ejguy said:
Our systems are all waste spark so hard to do on odd numbers of cylinders plus only a tiny market for Experimental radials so there would be a very long return on investment to develop new hardware and software.
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Can you PM me an estimate on the development cost?
 
I got an email today asking about the CPI2 face plate size.

Initially, we were planning an instrument with about a 2.75 X 2.75 inch square footprint in order to fit the larger LCD screen. We could also go up to a standard 3 1/8 round face. Our original goal was to take up minimal panel space for new builds but perhaps many existing aircraft will have a spare round instrument hole open.

Any preference? Should we offer both?
 
Thanks for asking.

My 1st preference is a 3 - 1/2" multi-color display, sized to fit standard 3-1/8" instrument cutout.

Second preference would be a standard round instrument, the size you use in your SDS EM-5 FI system.

BTW, I met and spoke with Bill Beaton at Reno about his experiences with the SDS system. All good.
 
On the CPI2, we looked at doing a color MFD but the development costs put that outside the market for this device which is intended mainly to compete with the P mag, Surefly, Electroair and Lightspeed ignition systems. Most of these have no or no standard human interface available. Also, since programming is nil or minimal, it does not warrant such a display for just showing timing, MAP and a few other simple parametera 99% of the time.

The larger 12 X 2 display simply won't fit into a 2.25 round package along with decent sized buttons so it must be larger than that.

Appreciate the comments and glad you talked to Bill who's been flying and racing our stuff.
 
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SDS

I suggest that you make the unit blind behind the panel and WIFI the out put to a Droid pad that will show what the SDS EI is doing in graphs.Program the unit through WIFI and have as many programs as you want like for each altitude you fly,climb,and descent,LOP and best MPG.And that's just the start of possibilities.
Thanks Bob
 
6 Gun said:
I suggest that you make the unit blind behind the panel and WIFI the out put to a Droid pad that will show what the SDS EI is doing in graphs.Program the unit through WIFI and have as many programs as you want like for each altitude you fly,climb,and descent,LOP and best MPG.And that's just the start of possibilities.
Thanks Bob
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For blind mounting you could just use the existing CPI.

There just isn't much to do with an ignition controller that requires such a screen or interface and we couldn't justify development the development time or expense in this market.

A complete engine controller with fuel and spark, that's a different matter because there's a lot more going on and you want a lot more info available. The next gen EM-X will be quite different in this regard and other regards but that's another project, separate from the CPI.
 
A D-10 style head unit would service the steam as well as glass crowd, but I struggle with devoting that much real estate to an ignition system. The current CPI has some great SA features, but really, once it is programmed you really don't pay any attention to it. It's not an EMS... It's a "set and forget".
 
Set and forget per Toolbuilder

Yes, I am mounting 2ea CPI in -4 with limited panel. The boxes will go in a hinge down mounting from the bottom of the instrument panel. Logic used is you do need to fiddle with it from the cockpit initially as opposed to the avionics deck under the boot cowl.
 
Thinking way outside the box.
You really only need the screen for setup, or trying to determine what a problem is. So after configured, 99.9% of the time it is wasted space.
Therefore, a miniature version of something like this:
http://www.eclipserackmount.com/pro...nv-SfCO5K2r0bzPZ7RUqotYP-AsKvHaxoCy5AQAvD_BwE

The screen, and any controls slide and hide into the panel.
So when not used, the front face could be a 1/2in tall and three/four inches wide....

Tim
 
Ross, for CPI, perhaps a Wifi or USB connection to a remotely mounted controller isn't so crazy. It really is set-and-forget for most people.

The EDIS ignition I'm flying is set up via USB. Works great. It's only a pain when trying to use my clunky old laptop in the RV-8 cockpit while flying, something only us wackos tend to do. I'd LOVE a connection to my android phone, hard wired or wifi.
 
There will be voltage monitoring for the main bus power as well as backup battery health which we'd like to display easily for everyone so they have go- no go info on the panel and know what's going on with the unit.

While I see the benefit of downsizing or eliminating a dedicated screen and keypad, we've had a number of people say they are not keen on a bunch of devices dangling loose in the cockpit joined by external cables. It seems to me if you use your phone to display something, whether that's GPS info or ignition controller info, then you want a mount for that phone, so why not just have the controller head attached to the controller? A wireless connection saves the ugly cable bit at least. Again, I think we're up against time to develop and test things like this.

With the old or new CPI, you can still blind mount if you don't have the panel space.

We are looking at BlueTooth for some other projects and this could find its way in some form into the new CPI. Then do we have to write software for both Android and Apple devices? You see where this is going as far as lead time goes? We are not a Garmin or Dynon unfortunately as far as engineering resources available.

Appreciate the input, it's always food for thought.:)
 
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"There will be voltage monitoring for the main bus power as well as backup battery health which we'd like to display easily for everyone so they have go- no go info on the panel and know what going on with the unit."

As someone seriously considering the SDS proposed backup battery solution, I would appreciate a voltage monitor option built into the system. The monitor in my field of view.
 
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Chkaharyer99 said:
"There will be voltage monitoring for the main bus power as well as backup battery health which we'd like to display easily for everyone so they have go- no go info on the panel and know what going on with the unit."

As someone seriously considering the SDS proposed backup battery solution, I would appreciate a voltage monitor option built into the system. The monitor in my field of view.
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I know in the meter industry (think buildings) there is a standard for reporting a lot of this information. Allows you to interchange a fair number of parts.
Is there anything like that in avionics? Is there a standard way to report volt,amp,current to the EFIS?

Tim
 
There are several standard protocols in avionics depending whether it's serial or CAN data.

Simple display formats for some EFIS' is readily available, others are either proprietary or pay for use, especially where more complex functions are desired.
 
CPI2 Work Update

We've been a bit busy shipping orders lately but have almost licked all the OV protection and battery switching hardware issues on the breadboard. Some final testing tonight throwing 100 volts on the input and making sure nothing fries.

Next, we'll work on a backup battery charging circuit and then on to the prototype PCB layout of components.

The OV and backup battery circuitry soaked up a lot of hours as we had not done a lot of work along those lines previously. PCB layout should go quickly outside of some of the new bits/ features added.

Software will mostly be copied over from the existing CPI, again with additions for new features. This part usually goes pretty quickly- knock on wood.

We've looked at the mechanical layout and CNC machining of the new enclosure. This will probably be done quite differently than some of our other enclosures given the optional twin board layout. Still investigating the best way to accomplish all goals within price targets.
 
rv6ejguy said:
On the CPI2, we looked at doing a color MFD but the development costs put that outside the market for this device which is intended mainly to compete with the P mag, Surefly, Electroair and Lightspeed ignition systems. Most of these have no or no standard human interface available. Also, since programming is nil or minimal, it does not warrant such a display for just showing timing, MAP and a few other simple parametera 99% of the time.

The larger 12 X 2 display simply won't fit into a 2.25 round package along with decent sized buttons so it must be larger than that.

Appreciate the comments and glad you talked to Bill who's been flying and racing our stuff.
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2 1/4 hole for me - get bigger and its a pain for anyone with a small panel space. Larger hole guys can still use the small display, but not the other way around......
 
I'll second the above comment - ignition management has almost zero space budget in most instrument panel layouts, simply because the steam gauge heritage of many panels is also shared with a magneto ignition heritage where ignition management was a key switch.

Keep the controller small, please.

PS: Even in our current all-glass panel, I do not have, and will not make room for a 3 1/8" ignition controller. I would rather have a "flat pack" than a 3 1/8" instrument layout. (check out TruTrak autopilots for an example of a very viable flat pack configuration)
 
We're hearing as small as possible from most folks. We'll head that direction given the constraints of the 12 X 2 LCD. This unit will be at least 5 inches deep behind the panel though.
 
rv6ejguy said:
We're hearing as small as possible from most folks. We'll head that direction given the constraints of the 12 X 2 LCD. This unit will be at least 5 inches deep behind the panel though.
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On the key comment, you can do a lot with a knob ie push/pull, left/right up/down detents, as well as the basic twist function - less space than arrow keys.....just a thought.
 
maniago said:
On the key comment, you can do a lot with a knob ie push/pull, left/right up/down detents, as well as the basic twist function - less space than arrow keys.....just a thought.
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True but more complicated, expensive to manufacture, less reliable in our experience. The design will be one piece and the PCB take up a certain amount of space/ volume. This and the size of the LCD are the driving force for panel face size. We also want to keep the architecture familiar to legacy SDS users since some may want to upgrade at some point.

I've used some other products with multi-function knobs and minimalist keypads. I haven't liked any of them- not intuitive to use IMO.
 
rv6ejguy said:
True but more complicated, expensive to manufacture, less reliable in our experience. .
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True. The buttons on my kid sisters speak and spell still get the job done......well.... I suppose it does. Havent seen it nor my sister for 40yrs LOL...
 
Is it absolutely necessary to have the SDS CPI control panel pilot-accessible during normal flight? Could it be remotely mounted (like the forward baggage compartment in an -8?) I would consider buying this system now if the current control head could be remotely mounted (and wait for the smaller head once it is developed.)
 
maus92 said:
Is it absolutely necessary to have the SDS CPI control panel pilot-accessible during normal flight? Could it be remotely mounted (like the forward baggage compartment in an -8?) I would consider buying this system now if the current control head could be remotely mounted (and wait for the smaller head once it is developed.)
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Absolutely no requirement to access it in flight. You can buy the system, load the curve, and forget about it.
 
maus92 said:
Is it absolutely necessary to have the SDS CPI control panel pilot-accessible during normal flight? Could it be remotely mounted (like the forward baggage compartment in an -8?) I would consider buying this system now if the current control head could be remotely mounted (and wait for the smaller head once it is developed.)
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You'll be able to remote mount either the present CPI or new one as many have already done. Once programmed, most people would have no need to access the panel. BTW, we pre-program a base map into each unit for your CR and intended fuel octane despite misinformation posted in some other threads. You don't need to do anything other than verifying your initial timing is correct and running it, just like a P Mag or LS.

We have no plans at this time to offer a remote box with a smaller display head. The integrated design is what most have wanted and it keeps the costs where they need to be. We have other projects to work on immediately after the new CPI is designed, tested and in production.
 
I've been reviewing the SDS CPI documentation and I've determined that I would need to install a second alternator (or another backup battery) which would essentially equalize the cost between P-Mags and the SDS CPI for a split EI/mag ignition system in my plane. The installation process is a bit more complicated for the CPI, particularly for a existing aircraft, but I will be changing my alternator belt during my CI / MLU period this month, so it's not a huge consideration.

One question that came up is will the magnets on the ring gear negate the prop balance I had done a few months ago by Sensenich? - they mounted the weights on the ring gear.

Has anyone installed the magnets with the ring gear in place?

And I wish that the CPI install manual had a few more photo of the magnet install process.

Is the new CPI2 version going to change the coil pack, or the hall effect sensor? Or maybe the better question is what will be changing?
 
CPI Next Gen

Looks like most considering the purchase of the CPI are concerned about the size and mounting of control head display.With just a small mod the brain box could be made any size and the display head could be mounted anywhere by using phone jax and phone cord like most ELT's that way control head could be mounted separate anywhere.If WIFF or Bluetooth is not in the picture at this time.
Bob
 
We've set the design as a 1 piece unit as we feel this is the best design compromise in keeping costs to plan while having the real estate to include a user interface to program in flight.

If people don't want to allocate any or very small panel space, they can remote mount the present CPI or even the new one. With no interface (keypad) the product becomes the same as the other EIs which also have none and you can take your pick. We've seen a pretty big market from those who want easy adjustability in a low cost, reliable EI and we want to continue to fulfill that niche. We realize we can't be all things to all people.

We've sold a lot of systems for 6 cylinder Lycomings where the competition has made only hollow promises year after year. We'll continue to fill that market which is currently bigger for us than 4 cylinder setups.
 
"maus92 I've determined that I would need to install a second alternator (or another backup battery) which would essentially equalize the cost between P-Mags and the SDS CPI for a split EI/mag ignition system in my plane. The installation process is a bit more complicated for the CPI, particularly for a existing aircraft, but I will be changing my alternator belt during my CI / MLU period this month, so it's not a huge consideration. "

- Your choice, but if the CPI is running redundant to the mag (or vice versa), why go thru all the trouble of redundant alt & battery too? After all the redundant ignition system is there to get you to the next safe airport not across the country. Running CPI just gives you the advantage of a more optimized performance over the (now redundant) mag system.

One question that came up is will the magnets on the ring gear negate the prop balance I had done a few months ago by Sensenich? - they mounted the weights on the ring gear.

- the material drilled out in the three 1/8" magnet holes are refilled with the magnet/plug/epoxi resin so disturbance of the prop dynamic balance should be very minimal. The weights Sensenich mounted on the ring gear shouldn't affect the CPI magnets installation.

Has anyone installed the magnets with the ring gear in place?

-can be done on the plane, but much easier done with the flywheel off the plane, plus gives you access to the front of the case for installation of the crank timing sensor, you will have to trial fit the flywheel over the sensor a couple times to get proper clearances. Overall removing the prop only takes a few minutes, if care is taken to mark it's position on removal, all bolts are kept in the same holes, when re-installed your prop dynamic balance will not have changed, and the overall CPI installation is much easier.

Looks like most considering the purchase of the CPI are concerned about the size and mounting of control head display.With just a small mod the brain box could be made any size and the display head could be mounted anywhere
Bob

-the CPI control head is the brain box & is quite small, & could be mounted anywhere; behind some pop-out cover or component, sub-panel, side of cockpit, or where ever, you could even fashion the harness to make it 'pull out' to have access to it only when you want to make an adjustment.
In a Rocket installation I left the wiring harness about 30" long so the pilot could pull it out & make minute adjustments than tuck it away above his console, held in place with velcro.
In actual operation the CPI only needs a few adjustments on initial installation/setup, after which it just sits there & does it's thing.
 
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In light of the ongoing discussions about lithium batteries and alternator OV controls, we've concluded that we may not be able to rely on the fact that other devices can keep high voltages from occurring on the main bus.

We're working on our own internal solution to make sure the CPI2 continues to run the ignition no matter what X battery or X alternator does or doesn't do.

This may add another week or so to development time but I'd hope it will give people buying our product a bit more peace of mind.
 
SDS CDI - This thread is a little stale. Can we get an update from SDS on the state SDS news.... What changes have been made in a last year and what is to come. Thanks.
 
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