VEMS Community Forum

Technical => Fuel Injection => Topic started by: Mac-B on May 16, 2014, 09:47:50 AM

Title: Max. Current with Low-Z-active flyback 8ch
Post by: Mac-B on May 16, 2014, 09:47:50 AM
Hi,

I´m wondering if I´m actually stressing my VEMS to much:
I drive 3 low-z injector in parallel out of one channel with 40% PWM, 2 channels with 3 injectors each

If i´m getting it right, default setup is high-z injector (>=12Ohm)
12V/12Ohm --> approx. 1A

In my setup i have 3 low-z injectors with 2,35Ohm each in parallel. -> R_total is 0.7833 Ohm
12V/0,7833Ohm*0,4 (PWM) --> 6,12A

Is that calculation right  ?
Is the low-z-board / the VEMS capable of that ?
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: Mac-B on May 16, 2014, 10:06:21 AM
Second option would be to go sequential with the stock injectors:
12V/2,35Ohm * 0,4(PWM) = 2,04A

Is that OK compared to the 1A for 12Ohm injectors ?
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: MWfire on May 16, 2014, 12:45:51 PM
peak current is around 3-4A per injector and 1A during pwm(if it's good configured).
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: Mac-B on May 16, 2014, 01:12:18 PM
Quote from: MWfire on May 16, 2014, 12:45:51 PM
peak current is around 3-4A per injector and 1A during pwm(if it's good configured).

in which setup i mentioned ?
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: VEMS on May 16, 2014, 01:40:08 PM
Hello Mac-B,

I would advice to use 1 injector per Injector output when running Low-Z injectors. You can still fire multiple injectors from one injgroup if desirable (see Base Setup -> Injector Outputs Visual to configure it).

Best regards, Dave
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: Mac-B on May 16, 2014, 02:19:54 PM
OK. Understood.
But what is the unit capable of ?
Title: Re: Max. Current with Low-Z-active flyback 8ch
Post by: VEMS on May 17, 2014, 11:58:31 AM
Current ratings for each channel are listed in VemsTune -> Outputs -> Assign output channels or also available on  http://www.vems.hu/wiki/index.php?page=GenBoard/Manual/DigitalOut/Table

Best regard, Dave