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mb911 |
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#1
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,572 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
So was noticing I have less voltage while the car is running. I am use to seeing 13/14 volts as the pretty much normal. I have a fairly new marchel alternator and this year I am seeing 13v on the high side. Now I do have more electrical items, wide band o2, mega squirt, and active exhaust. Regulator going bad? Pictured in upper left. Hmm maybe I have them on the wrong pins? Might have messed that up?
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technicalninja |
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#2
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,531 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region ![]() ![]() |
Not sure if this will help...
The late model Miatas have a generator and the voltage regulator is the ECU. Megasquirts can be arranged to provide this. You end up setting a "target voltage" in parameters in the squirt. Don't know if this is applicable to a Porsche generator but the hard work may have already been done. If you want to try it look to the Mazda solution for directions/ideas. "Late" Miatas mean NB1s and NB2s for me. So, the years I'm referring to are 99-05. I think some of the NAs pre 99 also did this as one of the old school mods to make this work was installing a 90-93 alternator in the newer model. After they figured out how to work it in the squirt no one puts the old alternator in anymore. |
mb911 |
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#3
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,572 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
Not sure if this will help... The late model Miatas have a generator and the voltage regulator is the ECU. Megasquirts can be arranged to provide this. You end up setting a "target voltage" in parameters in the squirt. Don't know if this is applicable to a Porsche generator but the hard work may have already been done. If you want to try it look to the Mazda solution for directions/ideas. Hmm that’s interesting and good to know. I am learning MS right now. It is an amazing ECU for the money |
ClayPerrine |
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#4
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Life's been good to me so far..... ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 16,370 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille ![]() ![]() |
Not sure if this will help... The late model Miatas have a generator and the voltage regulator is the ECU. Megasquirts can be arranged to provide this. You end up setting a "target voltage" in parameters in the squirt. Don't know if this is applicable to a Porsche generator but the hard work may have already been done. If you want to try it look to the Mazda solution for directions/ideas. Hmm that’s interesting and good to know. I am learning MS right now. It is an amazing ECU for the money You can control an alternator with Megasquirt. I have it in process for my 4.0 engine. It can't be done with the later internally regulated alternator, but it can be with the external regulated alternator. From the MS3Pro manual: High speed feedback field control: A different method of closed loop alternator field control, similar to an electronic version of a points type regulator. The MS3Pro monitors the battery voltage at 20 kHz and switches the field off if it is above target voltage, and switches the field on if it is below target voltage. Often easier to set up than closed loop field control, as there are no PID parameters to tune - you just need to select this mode and set a target voltage. If the ECU is controlling the field coil directly, we recommend running the output through a solid state relay or external power transistor. Many alternator field coils may require 10 amps or more, which is more than the MS3Pro’s recommended output current. You can replace the voltage regulator with a solid state relay, and use the Megasquirt to control the relay. the DF wire should be connected to pin 87 of a Bosch solid state relay, and pin 30 connected to the battery positive post. Pin 85 would connect to the ECU and pin 86 would connect to ground (I think...It may have to connect to 12v. Consult the Megasquirt manual). The programming should be fairly simple. You will have to make the generator light trigger from the ECU if you want to have it work. If you do it, let us know how it works. Clay |
mb911 |
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#5
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,572 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
Not sure if this will help... The late model Miatas have a generator and the voltage regulator is the ECU. Megasquirts can be arranged to provide this. You end up setting a "target voltage" in parameters in the squirt. Don't know if this is applicable to a Porsche generator but the hard work may have already been done. If you want to try it look to the Mazda solution for directions/ideas. Hmm that’s interesting and good to know. I am learning MS right now. It is an amazing ECU for the money You can control an alternator with Megasquirt. I have it in process for my 4.0 engine. It can't be done with the later internally regulated alternator, but it can be with the external regulated alternator. From the MS3Pro manual: High speed feedback field control: A different method of closed loop alternator field control, similar to an electronic version of a points type regulator. The MS3Pro monitors the battery voltage at 20 kHz and switches the field off if it is above target voltage, and switches the field on if it is below target voltage. Often easier to set up than closed loop field control, as there are no PID parameters to tune - you just need to select this mode and set a target voltage. If the ECU is controlling the field coil directly, we recommend running the output through a solid state relay or external power transistor. Many alternator field coils may require 10 amps or more, which is more than the MS3Pro’s recommended output current. You can replace the voltage regulator with a solid state relay, and use the Megasquirt to control the relay. the DF wire should be connected to pin 87 of a Bosch solid state relay, and pin 30 connected to the battery positive post. Pin 85 would connect to the ECU and pin 86 would connect to ground (I think...It may have to connect to 12v. Consult the Megasquirt manual). The programming should be fairly simple. You will have to make the generator light trigger from the ECU if you want to have it work. If you do it, let us know how it works. Clay 1st thing is first and get a regulator on there and tune the car. Then I will tackle that. I am learning autotune now. |
ClayPerrine |
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#6
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Life's been good to me so far..... ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 16,370 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille ![]() ![]() |
Not sure if this will help... The late model Miatas have a generator and the voltage regulator is the ECU. Megasquirts can be arranged to provide this. You end up setting a "target voltage" in parameters in the squirt. Don't know if this is applicable to a Porsche generator but the hard work may have already been done. If you want to try it look to the Mazda solution for directions/ideas. Hmm that’s interesting and good to know. I am learning MS right now. It is an amazing ECU for the money You can control an alternator with Megasquirt. I have it in process for my 4.0 engine. It can't be done with the later internally regulated alternator, but it can be with the external regulated alternator. From the MS3Pro manual: High speed feedback field control: A different method of closed loop alternator field control, similar to an electronic version of a points type regulator. The MS3Pro monitors the battery voltage at 20 kHz and switches the field off if it is above target voltage, and switches the field on if it is below target voltage. Often easier to set up than closed loop field control, as there are no PID parameters to tune - you just need to select this mode and set a target voltage. If the ECU is controlling the field coil directly, we recommend running the output through a solid state relay or external power transistor. Many alternator field coils may require 10 amps or more, which is more than the MS3Pro’s recommended output current. You can replace the voltage regulator with a solid state relay, and use the Megasquirt to control the relay. the DF wire should be connected to pin 87 of a Bosch solid state relay, and pin 30 connected to the battery positive post. Pin 85 would connect to the ECU and pin 86 would connect to ground (I think...It may have to connect to 12v. Consult the Megasquirt manual). The programming should be fairly simple. You will have to make the generator light trigger from the ECU if you want to have it work. If you do it, let us know how it works. Clay 1st thing is first and get a regulator on there and tune the car. Then I will tackle that. I am learning autotune now. I would agree with that. Keep it simple at first, then add things like this later. I honestly thought you already had it running well on the Megasquirt. Clay |
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