Understanding the FFH better with a ScanGauge

[hybridbear]

I recently bought and installed a ScanGauge II in our FFH. After driving a 100+ miles with in installed over the past few days I have a number of observations and a number of questions...

 

Observations

• Horsepower - the generator can place about a 15 horsepower load on the ICE when the battery is low and the ICE is doing maximum recharging. This is good for about 18 amps of current flowing into the HVB. In other situations it seems that each hp of ICE output to spin the generator is good for slightly more than 1 amp of current flowing into the HVB.
• Amps - the maximum regen braking charge seems to be about 30-35 amps. I've never seen the regen braking charge go above 35 amps while still getting 100% brake score. That seems to be the limit for the generator. When driving in EV 1 bar on the Empower screen is about 20 amps of current flowing out of the battery. The max current I have seen flowing out of the battery has been about 50 amps. This happened when I was accelerating in EV at 1.5 or 1.75 bars and then it kicked over to the ICE. Since one motor/generator must spin the ICE up to speed (like a starter motor in a conventional car) there is a momentary spike in amps flowing out of the battery to start the ICE.
• Recharging - The computer likes to charge the battery with a 15 amp current flow when the battery SOC is low to maybe about 75% of the display. This seems to be in the most efficient range of the ICE as well as the LOD will often be 85+ when this load is placed on the ICE by the generator while accelerating. When the battery SOC is higher than 75% of the battery icon the amps from the ICE generator drops to 5-8 amps. If the battery is almost full the current flow drops to about 3 amps.
• Coasting - when coasting with your foot off the gas pedal the generator places about a 3-5 amp load to gradually slow the car down.
• Idling - when idling the current draw to run the computers and charge the 12V battery is about 0.55-0.60 amps. This amount of current is drawn whether the car is in Park, Reverse, Neutral or Drive as long as you are not moving. The brake lights pull a minimal amount of current, but enough to make this range 0.59-0.64 amps when you are stepping on the brake.
• Lights - the headlights/taillights draw about 0.25 amps. The park lights and fog lights draw the same amperage as the headlights. If you combine headlights and fog lights the current draw is about 0.40 amps.
• HVB temps - the HVB temp quickly increases when driving from the current flow in and out of the battery. The past few days each morning the HVB temp showed the same as the exterior temp when first starting off (between 75 & 80 F) but quickly warmed up about 10 degrees within the first few miles of driving. Only on Friday where we did a lot of driving in the city in 95 F outside temps did the HVB temp go above 100 F. The HVB fans ran non-stop on Friday. Other days I noticed that at about 85 F HVB temp the fans would kick on at a low RPM (about 750-1000 showing on the display). On Friday I saw the HVB Fan RPMs as high as 2000. Even when running at that speed I still couldn't hear the fan when I got out of the car to listen with it "running" and with the SGII indicating a fan speed of 2000. I imagine that when we hear the fan running from outside the car after the car is off it must be running much faster than 2000 RPM.
• Current draw when off - after turning off the car in the few seconds before the SGII turns off the power draw shows 0.04 amps. This is likely to run whatever computers are still active to display the Trip Summary and Lifetime Summary screens.
• AC amp draw - the AC will draw 15-20 amps from the HVB when first turned on with a hot car. Once the car has cooled down the AC continues to draw an extra 2-3 amps minimum that we observed. This puts some numbers to the effect of AC on gas mileage. That is a lot of current that must be replaced by burning gasoline.
• Battery display on dash without charge/discharge arrows - It is very hard to get the battery display to show no arrows for charging or discharging. It appears that while moving the car displays no arrows when the current flow is less than 1 amp in or out of the HVB. However, sometimes the current flow will be less than 1 amp and the dash will still display arrows for charging or discharging. Also, when stopped a current flow of less than 1 amp displays as the HVB is discharging. No matter how hard I've tried I have never been able to get the display to show 0.00 amps as the current flow. With steady pedal pressure it is possible to keep the amp flow steady for many seconds though while driving as long as the slope of the road doesn't change.
• Warm up stages - when the ICE is in S1a the power demand on the ICE is very low, less than 10 hp and a LOD less than 60, this is quite inefficient and shows why skipping stage S1a improves fuel economy so much as discussed here

Questions :headscratch:

• What exactly is LOD (Load)? The car often shows 95-99 when accelerating slightly more aggressively such as accelerating onto the freeway, when accelerating in the city it often shows only 80-85. When the ICE is idling in warm up the LOD is as low as 50. Is this the % of maximum power output of the ICE at the current RPM?
• How do I understand the ignition timing screen (IGN)? When the ICE is off it shows -10. When the ICE is on I've seen values anywhere from 5-8 (when ICE is under load accelerating) to 30+ (mostly when the ICE is under a light load but still on such as freeway driving where the Empower screen shows the power demand being just above the EV threshold.
• Why does the car show 1.2 horsepower when the ICE is off? I tried using the adjustment in the setup but even decreasing the reading by 10% only lowered the display when the ICE is off to say 1.0 horsepower. What does the default value of 1.2 hp when the ICE is off mean for the numbers that the SGII displays for hp while I'm driving?

As I think of more items I'll continue to add to this thread. As it stands now I hope that my observations will be of benefit to others and that those with more experience and knowledge than I will be able to shed some light on my questions. Thanks in advance for that help! :worship:

Edited September 18, 2013 by hybridbear

[acdii]

I think LOD refers to the amount of power being produced and being sent to the drive train. You want to maximize the amount of load on the engine at the lowest RPM, so a higher load at lower RPM is better than lower load at higher RPM. It is more fuel efficient to have more load at lower RPM than at a higher RPM, as you are getting more bang for the buck at that point.

 

 

IGN is spark advance. If the ICE isnt spinning, no timing, and since its an Atkinson cycle, timing is important, and you will most likely see a negative number during spin up just before it fires off, and the advance will vary depending on what the LOD is being called for. For the most power it needs to fire sooner to produce more flame. Do you know if it stated BTDC or ATDC? 30* BTDC is when the plug fires as the piston comes up, which is needed more as the egine is under load and spinning faster, the lower number 5* BTDC is about normal for a lightly loaded ICE.

 

 

Not a clue on the HP readings.

[vangonebuy]

I've believe load (lod) is resistance on the motor to turn.

Even running a motor in neutral will have some load.

 

I use it when going through the rolling hills of VT and ME.

When it gets to high. 85 - 90 + back off.

 

You are wasting fuel as you try to maintain speed uphill. Better to let off the gas. Lower the demand and increase fuel economy.

You will slow down though. Accessories, Lights, and A/C also affect load.

 

My SGII is still in my van. It needs the info more.

[hybridbear]

I think LOD refers to the amount of power being produced and being sent to the drive train. You want to maximize the amount of load on the engine at the lowest RPM, so a higher load at lower RPM is better than lower load at higher RPM. It is more fuel efficient to have more load at lower RPM than at a higher RPM, as you are getting more bang for the buck at that point.

 

 

IGN is spark advance. If the ICE isnt spinning, no timing, and since its an Atkinson cycle, timing is important, and you will most likely see a negative number during spin up just before it fires off, and the advance will vary depending on what the LOD is being called for. For the most power it needs to fire sooner to produce more flame. Do you know if it stated BTDC or ATDC? 30* BTDC is when the plug fires as the piston comes up, which is needed more as the egine is under load and spinning faster, the lower number 5* BTDC is about normal for a lightly loaded ICE.

That's what I thought about LOD. I figured that a higher LOD is better because then you're getting into the most efficient range of the BSFC graph.

 

What are BTDC and ATDC? IGN is one of the base SGII gauges so I have no idea what the source of the data may be in the car. I've noticed lower numbers for IGN when the LOD is higher generally speaking.

 

I've believe load (lod) is resistance on the motor to turn.

Even running a motor in neutral will have some load.

 

I use it when going through the rolling hills of VT and ME.

When it gets to high. 85 - 90 + back off.

 

You are wasting fuel as you try to maintain speed uphill. Better to let off the gas. Lower the demand and increase fuel economy.

You will slow down though. Accessories, Lights, and A/C also affect load.

 

My SGII is still in my van. It needs the info more.

I know not to try to maintain speed uphill. When I comment about accelerating faster to see 95+ LOD I'm talking about accelerating at 2 bars on the Empower screen. In the city when I'm only going up to 25 or 30 MPH then I don't accelerate as quickly just to have to slam on the brakes for the next light.

[acdii]

That's what I thought about LOD. I figured that a higher LOD is better because then you're getting into the most efficient range of the BSFC graph.

 

What are BTDC and ATDC? IGN is one of the base SGII gauges so I have no idea what the source of the data may be in the car. I've noticed lower numbers for IGN when the LOD is higher generally speaking.

 

 

 

Yep, nailed the BSFC part.

 

BTDC= Before Top Dead center

ATDC= After top Dead Center

 

BTDC is the spark firing as the piston approaches the top of the cylinder, at higher RPM and load the sooner if fires, the more complete the burn is, so every BTU is used to drive that piston down.

 

ATDC firing is not used very much as the force of the explosion is wasted since the piston is already on its way down, but given your reading of -10* leads me to think that the plug is firing on the down stroke to help spin up the ICE before it is placed under load, very little fuel is needed to do this, and takes some of the load off the MG.

[majorleeslow]

I was told that Ford social site you can ask all these questions to their technical team.

 

oh by the way scangage e is pretty much useless. Don't bother buying it if you plan to read amps and hp. I'll be looking for scangage ii and super glueing the old one to my van.

Edited September 5, 2013 by majorleeslow

[vangonebuy]

I recently bought and installed a ScanGauge II in our FFH.

 

hybridbear,

 

Before you get really into the mpg on SGII.

 

Do the speed calibration.

My van odometer was off, It skewed my speed and distance.

I prefer to use a GPS as a reference. But a measured mile will work too.

 

I dont have the SGII in the FFH.

But I've seen a 1 mph difference to my GPS @ 55mph.

Better than my van's accuracy, But still off.

[acdii]

 

hybridbear,

 

Before you get really into the mpg on SGII.

 

Do the speed calibration.

My van odometer was off, It skewed my speed and distance.

I prefer to use a GPS as a reference. But a measured mile will work too.

 

I dont have the SGII in the FFH.

But I've seen a 1 mph difference to my GPS @ 55mph.

Better than my van's accuracy, But still off.

I had to do the same when I used it in the other FFH. Makes a big difference when you start comparing dash vs SG vs actual. Once calibrated, the variance was well under 1%.

[hybridbear]

Yep, nailed the BSFC part.

 

BTDC= Before Top Dead center

ATDC= After top Dead Center

 

BTDC is the spark firing as the piston approaches the top of the cylinder, at higher RPM and load the sooner if fires, the more complete the burn is, so every BTU is used to drive that piston down.

 

ATDC firing is not used very much as the force of the explosion is wasted since the piston is already on its way down, but given your reading of -10* leads me to think that the plug is firing on the down stroke to help spin up the ICE before it is placed under load, very little fuel is needed to do this, and takes some of the load off the MG.

The -10 is what shows when the ICE is off. I have never seen a negative number for IGN while the ICE is on.

 

 

hybridbear,

 

Before you get really into the mpg on SGII.

 

Do the speed calibration.

My van odometer was off, It skewed my speed and distance.

I prefer to use a GPS as a reference. But a measured mile will work too.

 

I dont have the SGII in the FFH.

But I've seen a 1 mph difference to my GPS @ 55mph.

Better than my van's accuracy, But still off.

Thanks for the tip. For now I'm not planning to do anything with the MPG data the SGII can provide. I think the car provides enough feedback for that. I'm more interested in using the SGII to learn about how the two powertrains work together so that I can maximize my MPG by better understanding each system. That's why I'm currently displaying HP, LOD, HVB temp (XGauge item) and AMPs in/out of HVB (XGauge item). I have alternatively replaced HVB temp with IGN when it's cool and the HVB temp isn't a concern. So far my focus has been gaining a better understanding of ICE operation and how my foot on the throttle affects ICE operation. By learning that relationship I hope to be able to manipulate the ICE into running even more efficiently than the computer would do on its own.

[hybridbear]

Does anyone with an "underperforming" FFH have a SGII? If anyone with one of the "defective" cars has one I'd really like to chat and see if you can't figure out some of the possible causes using the SGII. I think it would help identify if the issue is the battery or charging system, etc...

[majorleeslow]

HB, just curious if you've eliminated all the other variables before going to SGII stuff.

 

Things I'd want to analyze first.

tire pressure (some times gages are off). I go exact to 1 digit past decimal on digital Gage.

LRR tires (I have Michelin energii)

Alignment

excessive hilly route.

note that climate control in the car is a horrible gas guzzler.

Short trips is another issue.

If you have leadfoot guzzlers behind you all the time.

All I'm saying is that every drivers conditions are different you may or may not have ideal to achieve the rated number.

This car can't be compared to Prius but more to a Camry or sonata hybrid. Priuses have tiny lawnmower engines.

 

However if you've done all of the homework and still have an issue then go for it.

[hybridbear]

HB, just curious if you've eliminated all the other variables before going to SGII stuff.

 

Things I'd want to analyze first.

tire pressure (some times gages are off). I go exact to 1 digit past decimal on digital Gage.

LRR tires (I have Michelin energii)

Alignment

excessive hilly route.

note that climate control in the car is a horrible gas guzzler.

Short trips is another issue.

If you have leadfoot guzzlers behind you all the time.

All I'm saying is that every drivers conditions are different you may or may not have ideal to achieve the rated number.

This car can't be compared to Prius but more to a Camry or sonata hybrid. Priuses have tiny lawnmower engines.

 

However if you've done all of the homework and still have an issue then go for it.

Our car does excellent on fuel economy. Our overall Fuelly number is lowered by two cross country road trips and by an unusually cold winter in MN last year.

 

I bought a SGII because I want to further maximize our performance. If you look at our last few Fuelly tanks they've all been over 50 MPG since the weather warmed up.

 

My comments is I'd like to compare my results with someone with a low MPG car to try to use the SGII to diagnose if their issue is battery performance, ICE performance or something else. Since with the SGII I can get detailed info about charge in and out of HVB, volts and temp among other things it would be easy to compare HVB performance. With the ICE I can compare HP, LOD and IGN timing among other things to see if their issue is ICE performance.

[majorleeslow]

That's fantastic, please keep on sharing the SGII info. I didn't catch that add the reason when you mentioned under performing mpg.

My long trips are the same it drops down to high 40's and shows like a sore thumb in the fuelly graph. Still scratching my head how Ford got away with the tripple combo 47. Makes no sense at all.

 

Since I don't have one I'm doing it trial and error. Looking forward to some good holiday sales to get one.

Edited September 9, 2013 by majorleeslow

[majorleeslow]

Wow HB congrats on the 700 mi tank quite an achievement. I've yet to join the 700 mile club. I don't think it will be this tank due to some hot weather around here.

Edited September 9, 2013 by majorleeslow

[corncobs]

.. Still scratching my head how Ford got away with the tripple combo 47. Makes no sense at all.

 

Just take a look at the highway test cycle and you can probably stop scratching your head. EPA's highway definition has almost nothing to do with normal people's understanding of highway travel.

[majorleeslow]

Exactly why I am scratching my head. I've yet to understand what generation the hwy test was written for.

[corncobs]

Exactly why I am scratching my head. I've yet to understand what generation the hwy test was written for.

I believe originally written ~1960 with some modification over the years. There is some history time line somewhere on the web.

[hybridbear]

I have made some discoveries with the ScanGauge. Rather than repost here I'm just providing a link: http://fordfusionhybridforum.com/topic/6994-fuel-economy-tip-list/?p=65974

 

I put them in the Fuel Economy Tip List topic since I figured that would be a better place to reach more users with the insights I've gained for maximizing fuel economy.

[corncobs]

Since I can't post it on the other page here are some of my thoughts.

 

HB you are saying it draws 20 amps at 1 bar. The HVB is approximately 300 VDC this would mean that at one bar the motor is drawing about 6kW.

 

mmhh know I forgot where I was going with that... hopefully it comes back to me.

[hybridbear]

Since I can't post it on the other page here are some of my thoughts.

 

HB you are saying it draws 20 amps at 1 bar. The HVB is approximately 300 VDC this would mean that at one bar the motor is drawing about 6kW.

 

mmhh know I forgot where I was going with that... hopefully it comes back to me.

When I've monitored the HVB voltage on the ScanGauge I've typically seen 275-285 volts. How do you use the volts and amps to calculate the work being done by the electric motor? I don't remember a lot from physics class anymore. I figured with the wealth of knowledge of other users on here we'll be able to make progress! Thanks corncobs!

[corncobs]

HB thanks for reminding me of my goal > trying to calculate the work done by the electric motor. Too many things going on in my head... ;-)

[murphy]

Volts times Amperes = Watts

 

Watts divided by 1000 = kW (kilowatts)

 

kW times Hours = kWh (kilowatt hours)

[acdii]

Well 30 years ago I studied electronics to repair televisions. I dont remember anything other than the terminologies.

 

However, Based on my experience with Electric RC and Lip batteries, there are thresholds to keep. Never exceed a set voltage, High or low. If you go below a set low voltage, you basically destroy the battery. The Computers in Hybrids control these voltages so that they never exceed either threshold, and in fact do their best to cycle the packs to keep them in peak performance.

 

In the 10-12 FFH the computer does an occasional peaking cycle where it hard charges the packs and keeps them at top level for a set time. First time mine did it made me thing the car broke since there is no EV at all during that time and the engine does not shut down until the cycle is completed. Funny thing is I got my best MPG during these times.

 

I dont know if the new Fusion needs to do this at all since the battery levels are much higher and cycle more often due to the higher EV speeds. What would be curious is at what voltage does it kick out of EV and what the peak voltage is on the pack. Its a 300 volt pack. Is it lithium Ion, or lithium polymer? Whichever they are, they are of very high quality and very high C rating. C rating is how fast you can discharge and charge the cell.

 

NiMh batteries are charged as one, where Lithium are charged per cell, and use a balance system to prevent one cell from being over or undercharged. It basically shunts current from the higher charged cells to the lower ones, so they all balance out. Very important since overcharging a cell is a bad thing, which could cause the cell to overheat, burst or catch fire.

 

My theory based on what I see with my lipo packs and how they perform.

 

As far as current draw, the computer will keep the amps within set limits to prevent pulling too much out of the pack at one time, which is where it will fire the ICE. This also is calculated based on its SOC, which is computed based on voltage, and uses a table that has how much current can be drawn at any given voltage, along with how quickly the voltage drops at any given amp draw.

 

An example is when I fly a Power 25 equipped plane using a 3S 35C 3200 mah pack, If I go wide open throttle, the voltage drops quick, then stabilizes and continues to drop at a steady rate until the low voltage cutoff occurs. If I go half throttle slowly the voltage doesnt drop right away, but as the mah starts to deplete the voltage will slowly drop, even if I go to wide open. If I fly with WOT bursts it will deplete the pack much faster than if I slowly go to WOT, and it will also heat the pack up faster, which in turn will cause the volts to drop. A higher mah, higher C pack will supply more current for a longer time before the volts start to drop.

 

I have a volt alarm that measures each cell in flight, and will alarm when it reaches a set voltage, usually 3.4 V per cell. If I fly WOT it will drop to this setting really fast, but if I fly at half throttle I can fly much much longer, even if I do a WOT burst and trigger the alarm I find that reducing throttle to half I can fly for a few more minutes before the alarm will trigger hard and I need to land. So in a sense what I am doing with the throttle management to extend my flight time and not kill the pack with the alarm and stick, the hybrid computers are doing the same thing, but at a much higher scale and more precision.

 

When it comes to charging, you can put the current back in based on the MAh and C rating of the pack. There are 2 C ratings, the higher rating is for discharge, or a 3300 mah 35C pack can be discharged at 35 times 3300 or 117 Amps. The lower C rating is how much you can charge it at, mine is 5C, so 5 X 3300 mah or 16.5 amps.

 

So hopefully based on this you can get an idea of how the charge/discharge system on the Hybrid can function, just at a much higher rate. I believe the max charge rate is 30 amps. If that is true, based on 1C it would mean the pack is rated at 30,000 mah. At a 5C rating 6000 mah. You cant put it back in as fast as you can take it out, but the Hybrid system comes pretty close.

[hybridbear]

HB thanks for reminding me of my goal > trying to calculate the work done by the electric motor. Too many things going on in my head... ;-)

Very cool! So...

 

280 volts x 20 amps = 5600 watts = 5.6 kW = 7.51 hp. This makes sense that the first line on the Empower screen would be about 7.5 hp considering that when the ICE is running at that line it typically shows about 21-23 hp with about 16-18 amps flowing into the battery. When idling with the ICE on I've determined that 14-15 hp from the ICE gets about 16-18 amps of charge flowing into the battery. So if we take away the 14-15 horsepower for the generator we're left with about 7.5 horsepower left to power the car. Very cool!!

 

Volts times Amperes = Watts

 

Watts divided by 1000 = kW (kilowatts)

 

kW times Hours = kWh (kilowatt hours)

Thank you for the reminder of how it works.

 

So hopefully based on this you can get an idea of how the charge/discharge system on the Hybrid can function, just at a much higher rate. I believe the max charge rate is 30 amps. If that is true, based on 1C it would mean the pack is rated at 30,000 mah. At a 5C rating 6000 mah. You cant put it back in as fast as you can take it out, but the Hybrid system comes pretty close.

The max charging I've observed is just over 40 amps. The max discharging I've observed is just over 50 amps.

[hybridbear]

Here's a question for everyone, any ideas of how to secure the cable? I used the velcro mounts to mount the SGII on the steering column behind the wheel but in front of the dash. In this location it doesn't block any of the dash and is completely visible behind the steering wheel. However, there is a lot of extra cable. Any ideas of how to best secure the extra cable? Thanks.