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well.... we certainly have different opinions on this one. I've been driving BEVs since 2008, and I can tell you that Inverters are capable of sensing their internal temps rapidly, and clamping down on current to reduce heat is the typical way they prevent damage to themselves.

The resolution of the sensor readings in those runs I don't think is fine enough to make any definitive statements. If it were just current versus inverter temp, on as fine a time resolution as possible, you may draw different conclusions.

..... unless we have an actual Ford Engineer to chime in, its just conjecture until disproved. One simple reversible mod to test the theory would be to splice in a chiller on the Inverter coolant loop and see if you get full current for more time by keeping the Inverter below xxx degrees.
We don’t need to guess. Ford has acknowledged “5 seconds” as a limit.

That’s a time limit, not a temp limit.

We also know that it’s often less than 5 seconds, but never more.

If it’s a time thing, you can’t trick a clock by changing temperature parameters.

Now your “trick” could make gray bars go away sooner after a run or at highway speeds for example if temp feedback limits it more in those situations.

For example you might get 3 seconds at 60-100 mph instead of 2.

But nothing like this will get you 6 seconds.

The resolution on the log is fine. You can clearly see the inverter temp drop to normal BEFORE the 5 second limit kicks in.
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We don’t need to guess. Ford has acknowledged “5 seconds” as a limit.
That’s a time limit, not a temp limit.
what is your source on this?
who and when?
Was it a Ford Engineer who disclosed any actual details on what parameters affect the time?

I am asking really just out of curiosity, not to be right or wrong. We have observable behavior, but no credible insider information on exactly what parameters the software is using to determine the time limit. Without getting some documentation on the programming or an interview from an Engineer involved in the control system, we're just guessing.

My point is simply that a mod to install a chiller on the Inverter Inlet would give some information.... it might make a difference, or it might not, but it would be information.

Compared to race tunes that ya'll have done on ICE cars, this is pretty easy and inexpensive.
 

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So question for all of you GT owners. If Steeda came out and said that the 5 seconds is all in the tune. We can remap the tune to give you 12 second of full power and make it a 11.?? Second car. We have done it and it doesn't seem to hurt the car but you will probably loose your warranty. Would you go for it.
YES!!!
 

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well.... we certainly have different opinions on this one. I've been driving BEVs since 2008, and I can tell you that Inverters are capable of sensing their internal temps rapidly, and clamping down on current to reduce heat is the typical way they prevent damage to themselves.

The resolution of the sensor readings in those runs I don't think is fine enough to make any definitive statements. If it were just current versus inverter temp, on as fine a time resolution as possible, you may draw different conclusions.

..... unless we have an actual Ford Engineer to chime in, its just conjecture until disproved. One simple reversible mod to test the theory would be to splice in a chiller on the Inverter coolant loop and see if you get full current for more time by keeping the Inverter below xxx degrees.
Well, if we want to play that game, I have had a Master's Degree in Mechanical Engineering since 1994 ;) Just a joke, but it is about as relevant as you having driven BEVs since 08.

Now, just to be clear, I realize there is a possibility that I am wrong and you are correct. It would not hurt my feelings if this turned out to be the case. But below is more explanation (beyond gut feel) of why I think what I do.

To me, its obviously time (open-loop). We know from many tests that the limit is pretty much exactly 5 seconds, regardless of weather, which would affect coolant temp. We also know that things are limited ALL THE TIME, and predictably, as SOC goes down, and/or speed goes up.

We also know that EVERY SINGLE GT or GTPE behaves exactly the same manner in this regard. Again, if it was a closed-loop system based on real-time measurements, there would be variability.

Lastly, modding an ICE car with just a tune is super easy. Buy a device, buy a tune (typically at the same time as the device), plug it into OBD port, and 10 minutes later you are done.

Now, you want to talk about swapping cylinder heads or something.... thats different.
 
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what is your source on this?
who and when?
Was it a Ford Engineer who disclosed any actual details on what parameters affect the time?

I am asking really just out of curiosity, not to be right or wrong. We have observable behavior, but no credible insider information on exactly what parameters the software is using to determine the time limit. Without getting some documentation on the programming or an interview from an Engineer involved in the control system, we're just guessing.

My point is simply that a mod to install a chiller on the Inverter Inlet would give some information.... it might make a difference, or it might not, but it would be information.

Compared to race tunes that ya'll have done on ICE cars, this is pretty easy and inexpensive.
Unfortunately I’ve only seen it once. But it definitely came from Ford.

It’s a disclaimer on a Ford Europe website as an asterisk on the 480 hp*.

It said “limited to 5 seconds.”

The when? Was around July 2021. Someone posted a direct link on the forum on one of the VERY long 5 second complaint threads.

Europe has stricter regulations when advertising power boosts or overboost features. They have to disclose the limitation. Probably why they only put it on the Ford Euro site and not in the US.

The lack of transparency has been a constant frustration though.
 


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Well, if we want to play that game, I have had a Master's Degree in Mechanical Engineering since 1994 ;) Just a joke, but it is about as relevant as you having driven BEVs since 08.
not really a joke.... but I understand the need to establish credibility. I got my BSME in '83, and the reason I mentioned BEVs since 2008 is that is when I converted and built my first BEV. I've built 3 since then. I am familiar with old-school controllers that had no temp sensors and would happily put thru full current until they popped. Next gen controllers like the Zilla and Soliton had internal sensors that would clamp current if the guts got too hot (usually around 140F), and they would reduce current until temps recovered, and the faster you cooled it, the sooner you got full current back. Burning up motors, controllers, and batteries with over-current for too long is the most common way to kill an EV.

If you have a degree in ME, I'm sure you remember Heat Transfer classes...... bigger delta T means more heat transfer.

This is the basis for my hypothesis that colder inlet temp to the Inverter will extend the time it will put thru full current by improving the heat transfer... The longer it takes the core temp to hit the trigger, the longer you have full power.

To me, its obviously time (open-loop). We know from many tests that the limit is pretty much exactly 5 seconds, regardless of weather, which would affect coolant temp. We also know that things are limited ALL THE TIME, and predictably, as SOC goes down, and/or speed goes up.
thats obviously NOT the conclusion I have drawn from the same set of data.... and here's why:

I would EXPECT the time to work out pretty much the same because all the tests so far are basically the same. They have been run in such a way that the system is testing the time to heat a closed loop system from the same 'starting' temp to the same 'trigger' temp with the same (max) current and the same heat transfer rate. We have to change either the starting temp (with a chiller), or the trigger temp limit (with a software hack that could result in damage).

This also explains why if you apply less than 100% throttle, you will see more than 5 seconds at that current until the system clamps down to recover. My hypothesis is.... once you exceed the current at which the existing cooling system can extract the heat, the time at that current depends on the heat transfer rate.

This also would explain why there is LESS THAN 5 seconds at full current if you have been motoring along at 80 mph up a hill for a couple minutes, and then floor it. My hypothesis is that under those test conditions the inlet temp would be somewhere between 'cool target', and 'max trigger' temp, spike sooner, and clamp current sooner. which matches real life driving experience where tests starting at 60mph may give you 5 seconds (or until you hit speed/rpm cap), but tests starting after a couple minutes at 80 wont.

The most practical way for a garage mechanic to change the heat transfer rate to see if it extends time at full current is to chill the inlet coolant temp below its 'factory' target temp, anticipating a large load, and enabling more heat transfer.... minor compared to blueprinting a motor, polishing ports, etc, etc,etc.

my point is that adding a chiller would be the only way to really test a different start temp and thus, heat transfer rate.
 

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So question for all of you GT owners. If Steeda came out and said that the 5 seconds is all in the tune. We can remap the tune to give you 12 second of full power and make it a 11.?? Second car. We have done it and it doesn't seem to hurt the car but you will probably loose your warranty. Would you go for it.

I would want to know a lot more about exactly what was changed in the 'tune' to determine for myself if the changed parameters might, or might not, 'hurt the car'.
 

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Unfortunately I’ve only seen it once. But it definitely came from Ford.

It’s a disclaimer on a Ford Europe website as an asterisk on the 480 hp*.

It said “limited to 5 seconds.”

The when? Was around July 2021. Someone posted a direct link on the forum on one of the VERY long 5 second complaint threads.

Europe has stricter regulations when advertising power boosts or overboost features. They have to disclose the limitation. Probably why they only put it on the Ford Euro site and not in the US.

The lack of transparency has been a constant frustration though.

Ford Marketing is a lot different source than Engineering if we are trying to determine what the limiting parameters/systems are.

That one sentence COULD be more usefully expanded if we knew the How or Why behind it. i.e. if we can get a Ford Engineer to fill in the blanks:

- time at full current is limited to approximately 5 seconds to avoid ___________, and availability to full power is restored when ___________.
 
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This also explains why if you apply less than 100% throttle, you will see more than 5 seconds at that current until the system clamps down to recover.
This isn’t true though. Going 90% throttle or 80% or anything close, still clamps down after 5 seconds.

You can’t trick the 5 second limit this way.
 
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Ford Marketing is a lot different source than Engineering if we are trying to determine what the limiting parameters/systems are.

That one sentence COULD be more usefully expanded if we knew the How or Why behind it. i.e. if we can get a Ford Engineer to fill in the blanks:

- time at full current is limited to approximately 5 seconds to avoid ___________, and availability to full power is restored when ___________.
Don’t need an engineer to fill those blanks, just someone to be able to get into the tuning tables that explain it.

And the answers aren’t gonna be words, they’ll be large tables with multiple parameters. We also kinda figured them out with trial an error.

Things that affect it:
Starting speed
State of charge
External temp
Battery temp
Throttle position
Time

And I’m sure there are more that could also limit it.
 

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not really a joke.... but I understand the need to establish credibility. I got my BSME in '83, and the reason I mentioned BEVs since 2008 is that is when I converted and built my first BEV. I've built 3 since then. I am familiar with old-school controllers that had no temp sensors and would happily put thru full current until they popped. Next gen controllers like the Zilla and Soliton had internal sensors that would clamp current if the guts got too hot (usually around 140F), and they would reduce current until temps recovered, and the faster you cooled it, the sooner you got full current back. Burning up motors, controllers, and batteries with over-current for too long is the most common way to kill an EV.

If you have a degree in ME, I'm sure you remember Heat Transfer classes...... bigger delta T means more heat transfer.

This is the basis for my hypothesis that colder inlet temp to the Inverter will extend the time it will put thru full current by improving the heat transfer... The longer it takes the core temp to hit the trigger, the longer you have full power.



thats obviously NOT the conclusion I have drawn from the same set of data.... and here's why:

I would EXPECT the time to work out pretty much the same because all the tests so far are basically the same. They have been run in such a way that the system is testing the time to heat a closed loop system from the same 'starting' temp to the same 'trigger' temp with the same (max) current and the same heat transfer rate. We have to change either the starting temp (with a chiller), or the trigger temp limit (with a software hack that could result in damage).

This also explains why if you apply less than 100% throttle, you will see more than 5 seconds at that current until the system clamps down to recover. My hypothesis is.... once you exceed the current at which the existing cooling system can extract the heat, the time at that current depends on the heat transfer rate.

This also would explain why there is LESS THAN 5 seconds at full current if you have been motoring along at 80 mph up a hill for a couple minutes, and then floor it. My hypothesis is that under those test conditions the inlet temp would be somewhere between 'cool target', and 'max trigger' temp, spike sooner, and clamp current sooner. which matches real life driving experience where tests starting at 60mph may give you 5 seconds (or until you hit speed/rpm cap), but tests starting after a couple minutes at 80 wont.

The most practical way for a garage mechanic to change the heat transfer rate to see if it extends time at full current is to chill the inlet coolant temp below its 'factory' target temp, anticipating a large load, and enabling more heat transfer.... minor compared to blueprinting a motor, polishing ports, etc, etc,etc.

my point is that adding a chiller would be the only way to really test a different start temp and thus, heat transfer rate.
Ok, so I took ChemE heat transfer in the early 90s, which must have differed from the ME HT because we learned about the affects of Thermal Capacitance. So I would challenge the notion that adding a chiller is the only way to test this when we have Mother Nature helping us with this project. The mass of the component housings sitting at 10deg F overnight will hold a lot of “cooling” capacity. That being said, I should be able to precondition my GTPE at 100% SOC so the batteries are happily warmed up, pull a few 0-100mph Mexico launches and not see the 5 sec throttling. Because the internals of the inverter will never hit a critical high temp with pounds of metal cooling them like a block of ice.
But since the 5 sec is hard coded by the engineers to shut down regardless of internal or external temps, it won’t matter.
 

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Ok, so I took ChemE heat transfer in the early 90s, which must have differed from the ME HT because we learned about the affects of Thermal Capacitance. So I would challenge the notion that adding a chiller is the only way to test this when we have Mother Nature helping us with this project. The mass of the component housings sitting at 10deg F overnight will hold a lot of “cooling” capacity. That being said, I should be able to precondition my GTPE at 100% SOC so the batteries are happily warmed up, pull a few 0-100mph Mexico launches and not see the 5 sec throttling. Because the internals of the inverter will never hit a critical high temp with pounds of metal cooling them like a block of ice.
But since the 5 sec is hard coded by the engineers to shut down regardless of internal or external temps, it won’t matter.
Love the discussion, I will just add that a cold soaked car, with no preconditioning is a great way to avoid the 5 second limit. Of course you are limited to 50%-60% power anyways so no how good that is in the real world ;). In those conditions, more and longer runs at max available power will actually unlock more power as the system heats up!
 

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Ok, so I took ChemE heat transfer in the early 90s, which must have differed from the ME HT because we learned about the affects of Thermal Capacitance. So I would challenge the notion that adding a chiller is the only way to test this when we have Mother Nature helping us with this project. The mass of the component housings sitting at 10deg F overnight will hold a lot of “cooling” capacity. That being said, I should be able to precondition my GTPE at 100% SOC so the batteries are happily warmed up, pull a few 0-100mph Mexico launches and not see the 5 sec throttling. Because the internals of the inverter will never hit a critical high temp with pounds of metal cooling them like a block of ice.
But since the 5 sec is hard coded by the engineers to shut down regardless of internal or external temps, it won’t matter.
Love the discussion, I will just add that a cold soaked car, with no preconditioning is a great way to avoid the 5 second limit. Of course you are limited to 50%-60% power anyways so no how good that is in the real world ;). In those conditions, more and longer runs at max available power will actually unlock more power as the system heats up!
Agreed with both of you. You can, with a GT, remote start the car, which will (we presume) heat the batteries, and avoid the initial "gray bars of sadness." It typically takes about 5 minutes, even on a 110V charge, or no charge at all. It doesn't appear to be running the coolant pumps during this time, at least when its cold. so the cold-soak in the coolant loop should remain relatively constant. And you still have the 5-second limit. I am certain the car is monitoring a variety of temperatures that influence power delivery. I am also nearly certain that the 5-second limit is simply a timer ;)
 

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Agreed with both of you. You can, with a GT, remote start the car, which will (we presume) heat the batteries, and avoid the initial "gray bars of sadness." It typically takes about 5 minutes, even on a 110V charge, or no charge at all. It doesn't appear to be running the coolant pumps during this time, at least when its cold. so the cold-soak in the coolant loop should remain relatively constant. And you still have the 5-second limit. I am certain the car is monitoring a variety of temperatures that influence power delivery. I am also nearly certain that the 5-second limit is simply a timer ;)
Remote starting (plugged in or not) will pre-heat the cabin, but not the battery (other than incidentally). To preheat the battery, you need to use a planned departure time which preconditions the battery - takes 45 minutes to an hour. Really wish Ford would add a way to do this for 1 time use instead of having to set and then delete a schedule each time.
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