Author Topic: Flyback connection with Power Flyback  (Read 8076 times)

Offline paul_f

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Flyback connection with Power Flyback
« on: July 01, 2010, 08:15:44 am »
I have the following Vems from April 2007 which I had the PowerFlyback installed in

Board_version=v3.3
Serial_nr= 624
pump-= 4.19V
wbo2_pump_pw_zero=0x68
wbo2_nernstdc_target=0x85
pump+= +2.0mV/200 Ohm
AREF=4.9V
(C103=1nF, no D100)

I am trying to work out how I should connect the flyback for the injectors, but it is difficult to work out from the Wiki.

I think from this page http://www.vems.hu/wiki/index.php?page=GenBoard%2FManual%2FPowerFlyback that I just need to connect Pin 23 to the injector common 12V.

Can anyone confirm that this is correct?

Thanks
Paul

Offline paul_f

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Re: Flyback connection with Power Flyback
« Reply #1 on: July 01, 2010, 08:30:30 am »
Oh and I will be using it with HighZ injectors

Offline GintsK

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Re: Flyback connection with Power Flyback
« Reply #2 on: July 01, 2010, 09:16:01 am »
Most probably you will get better control with 30V TVS diode and inline resistors  for each injector (no PWMing).
PowerFlyback prolongs injector closing too much from my experience. As result keep stable idle AFR becomes impossible.
But IIRC Power Flyback is connected in same way as 30V TVS diode. It can be done inside ECU or outside.

Offline paul_f

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Re: Flyback connection with Power Flyback
« Reply #3 on: July 01, 2010, 09:59:06 am »
I didn't think I needed resistors with HighZ injectors.  I thought only LowZ injectors need PWM or resistors?

Does the same apply for highz injectors - so I should remove the PowerFlyback and fit a 30V TVS diode instead?


Offline paul_f

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Re: Flyback connection with Power Flyback
« Reply #4 on: July 01, 2010, 10:58:17 am »
And if I should change to the 30V diode, what is the part number of the diode I should use (so I can see if we have one in the lab here)

Offline GintsK

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Re: Flyback connection with Power Flyback
« Reply #5 on: July 01, 2010, 01:58:57 pm »
Oh, sorry, my fault. Power flyback is just for Low-Z. And works bad.

Instead of power flyback you need just such diode:
http://uk.farnell.com/fairchild-semiconductor/1-5ke30a/diode-tvs-30v-1500w-axl-unidirc/dp/1700782



Offline paul_f

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Re: Flyback connection with Power Flyback
« Reply #6 on: July 01, 2010, 02:21:27 pm »
Oh, sorry, my fault. Power flyback is just for Low-Z. And works bad.

Instead of power flyback you need just such diode:
http://uk.farnell.com/fairchild-semiconductor/1-5ke30a/diode-tvs-30v-1500w-axl-unidirc/dp/1700782


Thanks for that, I have ordered one of those and I managed to find the information on the Wiki- so it seems that the TS diode just goes in place of the PowerFlyback between the green and red wire (disconnecting the PowerFlyback)