3-way solenoid flyback

[gox]

Hello ppl!

I`m installing the 3-way solenoid to work via MiscOut for the boost control and i`m not really shure how to wire a flyback for it? I saw on wiki that its recommended to have flyback if using injector output to control it?

Tnx

[mattias]

 Electrical connection

Connect a diode (like 1n4007 or BY399 or ES2J or similar)

    * Anode to switched point of the solenoid (channel output, EC18-pin..)
    * Cathode (marked with a line) to the other pad of the solenoid: the same where you connect the positive +12V (switched and fused) power

[gox]

Lets see did i get this right (i`m not an electronic expert :))

Like this (sorry for the drawing):

[peter_jensen]

Due it like this



Peter

[gox]

ok peter,thats the easier way then i thought to do it ;)

tnx

[GintsK]

Doesn't diode slow down boost solenoid operation?
I usually use INJ outputs with high voltage flyback for this purpose.

Gints

[gox]

Still need little help:

While i tested the solenoid (simply connecting it to the battery) i found which nipples flows when solenoid is off (not connected to the battery) and i set those nipples to be one feed from the turbine compressor and the other to the top of the wastegate,the nipple that gets flow after i connect the solenoid to +12 goes to the bottom of the wastegate,BUT when i connected the solenoid to the vems and set the miscout settings it all got messed up.I`m thinking that my solenoid is always switched on,since i see that solenoid pulls the vacum (engine is in vacum,so that is normal) on the nipple that goes to the bottom of the wastegate.I was playing with it until my laptop baterry died.I even tried with setting the "Minimum kPa" to 60kPa (engine is idling at 49kPa) and "Maximum kPa" to 90kPa and couldn't make it to see it clicking by reving the engine at idle...

Minimum RPM is set to 100 and Maximum RPM to 8000
I enabled the INJ H in the Injector Outputs (Decimal 64,EC36 Pin6)
Diode is connected as stated above in peter's post.

I couldn't figure out how to test the inj h with mdh command :(

[mattias]

Doesn't diode slow down boost solenoid operation?
I usually use INJ outputs with high voltage flyback for this purpose.

The whole point of the diode is to make the solenoid close faster, by killing the flyback voltage.

Still need little help

If your valve is a simple "2-3" valve you should connect the bottom part of the wastegate straight to the intake plenum after the throttle. The topside of the wastegate diaphragm can be connected via the valve to the compressor outlet. The valve will then switch boost into the topside (for faster spool) and let atmosphere in once boost has been reached, this can even be PWM controlled to give you a boost curve, effectively raising the boost by bleeding boost into the topside.

I couldn't figure out how to test the inj h with mdh command :(

Then don't figure it out, just use the output test function in VemsTune. In the  "injector outputs visual" dialog, activate test mode and click the buttons for each injector group.

[GintsK]

Doesn't diode slow down boost solenoid operation?
I usually use INJ outputs with high voltage flyback for this purpose.

The whole point of the diode is to make the solenoid close faster, by killing the flyback voltage.

This shouldn't be true. Valve closing is fastest with higher flyback voltage.  Voltage limiting is not for faster closing.
In IAC case diode gives smoother move of IAC choke. And this is what we need for IAC. But not for on/off type valves.

In 3rd page of this document is some example of relay delay depending of flyback type. As we see plain diode gives longest possible delay:
http://www.schrackrelays.com/appnotes/app_pdfs/13c3311.pdf

Gints

[mattias]

GintsK :  I never contradicted what you said, but maybe misunderstood what you meant as normal use (no diode). In general terms if you don't suppress the flyback voltage the closing of the solenoid will be slower - never mind the RFI considerations and potential damage to the switching element.