Downdraft design questions

That makes perfect sense. I appreciate it!

rodw wrote:

To go live, copy ddraft4x2.hal to your config folder and edit your ini file in a text editor (I use Geany!) and add it to the [HAL] section

This part requires the installation of Plasmac, correct?

I am still getting my base machine setup, as the instructions are pretty clear about getting the base machine dead-nuts before proceeding to Plasmac.

txtrone wrote:

rodw wrote:

To go live, copy ddraft4x2.hal to your config folder and edit your ini file in a text editor (I use Geany!) and add it to the [HAL] section

This part requires the installation of Plasmac, correct?

I am still getting my base machine setup, as the instructions are pretty clear about getting the base machine dead-nuts before proceeding to Plasmac.

You can do that now and plasmac should leave it alone. Note I uploaded a revised sketch of how to wire in the solenoids on your other wiring thread. The band on the diode points towards the mesa output. Pretty much any diode will do IN4004/IN4007 etc are as cheap as chips.

rodw wrote:

The band on the diode points towards the mesa output. Pretty much any diode will do IN4004/IN4007

On this type of series diode module, how would you connect the negative wire from the bus and the output from the Mesa card? Or does the output from the Mesa card attach to one side of the diode and continue thru to the solenoid? For instance, would the output from the Mesa card for solenoid #1 connect to terminal #1 on the diode block, then 'continue' out through terminal #2.... while the negative wire from the 2x bus connects direct to the solenoid?

After a little more research, I am thinking I need the time with a common anode. Something like this:

tommylight wrote:

That should be it for the non D versions of Mesa.
Preferably wait for PCW to confirm that.

Will do. I am just trying to round up material before the holidays... so I can work on it all next week.

I still can't wrap my head around where the diode needs to go.

ETA: I see you explanation in another thread. Let me make a quick schematic and post it up for verification.

The diode needs to go from the positive side of your solenoid inductor to the negative of your solenoid conductor with the "ring" pointing to the positive side.
The reason for this is that the moment you switch your solenoid off the magnetic field that was opening your pneumatic valve collapses and that changing magnetic field will induce a fairly large voltage in the solenoid inductor that can damage the drivers on the board. This induced voltage is inverted in polarity compared to the voltage you supply the inductor with so it will find a short circuit through the diode while your supply voltage will find the diode not conductive.
en.wikipedia.org/wiki/Flyback_diode

[edit]
Diode orientation:
electronics.stackexchange.com/questions/...al-diode-orientation