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Old 05-30-2013, 12:53 PM   #1
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Default alternator pwm

Did anyone try the alternator pwm in the newer alpha/betas yet?
New ms3 pro is underway (or rather, stuck in customs waiting for an absurd amount of taxes to be payed, as usual) and I'd rather not have a seperate alternator circuit if not needed.
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Old 05-30-2013, 01:07 PM   #2
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You don't need the separate circuit if you retrofit an NA8 alternator, which is a pretty simple job on a Hydra car, so i'd expect it to take all of 30 seconds with your eyes closed on a Megasquirt car.
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Old 05-31-2013, 10:08 AM   #3
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Quote:
Originally Posted by WestfieldMX5 View Post
Did anyone try the alternator pwm in the newer alpha/betas yet?
New ms3 pro is underway (or rather, stuck in customs waiting for an absurd amount of taxes to be payed, as usual) and I'd rather not have a seperate alternator circuit if not needed.
James & Ken used my 01 for implementing this feature into their code. Other than maybe some more tweaking to the PID values, it seems to be working very well so far. They added some clever controls, with voltage set points for after start, running, and fuel over run. I've been impressed with it so far, but for full disclosure, the car hasn't done more than idle and drive around our parking lot. Might find time to dyno it next week (hopefully).
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Old 05-31-2013, 12:07 PM   #4
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You don't need the separate circuit if you retrofit an NA8 alternator, which is a pretty simple job on a Hydra car, so i'd expect it to take all of 30 seconds with your eyes closed on a Megasquirt car.
You're suggesting swapping a NA8 alternator takes 30 seconds on a Hydra car and that swapping an alternator can be done with your eyes closed on a MS equppied car.

Alternator PWM is a really cool feature I hope fool around with on the next NB MS3x I build.
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Old 05-31-2013, 12:12 PM   #5
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I appears i originally mis-intepreted the OP. My apologies.
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Old 05-31-2013, 01:30 PM   #6
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If I may add a question: What or is there an advantage to the NB alternator control. I'm also getting an MS3 and was thinking of tossing an NAalt on just for kicks and to not mess with the control. Figured it's one less thing to mess with. Does the ecu control open up a whole new world of cool I don't see?
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Old 05-31-2013, 01:32 PM   #7
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From what i've read, the NA8 alternator isn't really the best unit in the world, and i would imagine that's most of the "want" for the NB alternator w/ control.

I simply don't care enough personally, and i'd rather just not **** with it.
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Old 05-31-2013, 01:51 PM   #8
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Quote:
Originally Posted by TorqueZombie View Post
If I may add a question: What or is there an advantage to the NB alternator control. I'm also getting an MS3 and was thinking of tossing an NAalt on just for kicks and to not mess with the control. Figured it's one less thing to mess with. Does the ecu control open up a whole new world of cool I don't see?
Your MS3 controls the stock alternator perfectly, no need to swap anything.
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Old 05-31-2013, 02:53 PM   #9
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Quote:
Originally Posted by concealer404 View Post
From what i've read, the NA8 alternator isn't really the best unit in the world, and i would imagine that's most of the "want" for the NB alternator w/ control.

I simply don't care enough personally, and i'd rather just not **** with it.

anything is better than a 1.6L alt.
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Old 05-31-2013, 02:56 PM   #10
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anything is better than a 1.6L alt.
You really didn't need the last three letters.
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Old 05-31-2013, 03:01 PM   #11
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well played.
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Old 05-31-2013, 05:09 PM   #12
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I have a spare 01 alternator if anyone wants to do some destructive testing.
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Old 07-31-2013, 04:16 PM   #13
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Been playing with the latest alpha but can't get stable voltage. Voltage creeps up from 13ish to over 18V. Changing pid parameters doesn't really do much. Anyone try it out yet / what settings did you use?
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Old 07-31-2013, 06:14 PM   #14
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Stop nagging about different alternators, for god's sake . I know about that and DO NOT want a different alternator.
I asked about the pwm control in the latest alpha. Is that so difficult to understand?

Jason, this is a MS3 Pro on a '00. Alpha5 has pwm control, but I can't get it stable, weird things happen when voltage swings up and down between 12.5 and 18V.
Seems I have 2 ways of controlling it: 'nothing' (as in about 12.8V stable) or 'too much' (as in voltage kreeps over 18V after a couple of minutes).
Will play with it some more tomorrow, if I can't get it stable, I'll build the hardware circuit.
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Old 08-01-2013, 09:51 AM   #15
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Is the software similar to boost control? have targets and PID?
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Old 08-01-2013, 12:13 PM   #16
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Can you log alt pwm and voltage and show us?
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Old 08-02-2013, 10:39 PM   #17
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The alternator's output is non-linear with duty cycle at extreme duties (high and low). You have to use the non-linear correction curve. If you want to email [email protected], ask me to send you the settings that work very well on my 01. Both the car and laptop are at work, so I don't have access to the tune right now from home.

There will still be momentary voltage spikes when high load devices shut off, but it is very similar to stock control. We spent a lot of time scoping the stock ECU's alternator output against Vbatt, and tuning the response of the MS3-Pro in my car to behave similarly.
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Old 08-10-2013, 12:36 PM   #18
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After failing the Binary JC alt control on anything than a stock Hitachi LR170-758 (a repaired one did not work), have the PWM been tested on more than the stock alts?

The PWM control would probably be the same since it tries to emulate the stock control, but I have seen some different input behavior while looking at the Field Out voltage on the JC circuit (different impedance or something, and different views of what zero is).

I just failed with a Mitsu Alt I pulled from my spare car...
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